Particles 2006
Medical/Biochemical Diagnostic, Pharmaceutical,
and Drug Delivery Applications of Particle
Technology
13-16 April 2006
Wyndham Resort Hotel, Orlando, Florida
3D Model of an Immunoliposome by Dr. R. Rezka, MDC, Berlin
Courtesy of Dr. Reto A. Schwendener
2
TABLE OF CONTENTS
Sponsors
4
International Organizing Committee
5
Exhibitors
6
General Program Schedule
9
Maps of Meeting Spaces
11
Technical Program
12
Abstracts of Oral Program
33
Abstracts of Poster Program
212
Author/Speaker/Presenter Index
273
List of Preregistered Conferees
278
Notes
304
3
Sponsors
Particles Conference
Division of Colloid and Surface Chemistry
of the
American Chemical Society
European Association of Pharma Biotechnology
American Association of Pharmaceutical Scientists
4
International Organizing Committee
J. M. Asua (Spain)
V. Babak (Russia)
J. R. Baker (USA)
F. Boury (France)
D. Burgess (USA)
K. Caldwell (Sweden)
R. Duncan (UK)
M. El-Sayed (USA)
N. Garti (Israel)
K. Johnston (USA)
H. Kawaguchi (Japan)
J. H. Kim (Korea)
C. M. Lehr (Germany)
S. Margel (Israel)
H. Moehwald (Germany)
B. Moudgil (USA)
R. Mueller (Germany)
F. Nielloud (France)
T. Nilsen (USA)
R. Pfeffer (USA)
D. Poncelet (France)
M. C. Roco (USA)
P. Rogueda (UK)
J. L. Salager (Venezuela)
S. Simoes (Portugal)
P. T. Spicer (USA)
S. Svenson (USA)
J. Texter (USA), General Chair
5
Exhibitors
CPS Instruments, Inc.
3755 Glenn Ridge Road
Furlong, PA 18925, USA
Telephone +1 215 794 2250
http://www.cpsinstruments.com/
FEI Company
5350 NE Dawson Creek Drive
Hillsboro, OR 97124, USA
Telephone +1 503 726 7500
Fax +1 503 726 2615
http://www.fei.com/
Horiba Instruments, Inc.
17671 Armstrong Avenue
Irvine, CA 91614
Telephone +1 949 250 4811
http://www.horibalab.com/
Inotech Biosystems International, Inc.
15713 Crabbs Branch Way, Suite 110
Rockville, MD 20855, USA
Telephone +1 301 670 2850
http://inotechintl.com
6
Liquidia Technologies, Inc.
P.O. Box 110085
Research Triangle Park, NC 27709, USA
Telephone +1 919 991 0835
Fax +1 919 991 0827
http://www.liquidia.com/
L.U.M. GmbH
Rudower Chaussee 29
12489 Berlin, Germany
Telephone +49-(0)30-6780 6030
Fax +49-(0)30-6780 6058
http://www.microtrac.com/
Microtrac
nd
12501-A 62 Street
North Largo, FL 33773, USA
Telephone +1 727 507 9770
http://www.microtrac.com
NOF Corporation
75 Aero Camino Blvd., Suite B
Santa Barbara, CA 93117, USA
Telephone +1 727 846 0866
Fax +1 727 846 0865
http://www.nof.co.jp/english/business/life/index.html
7
Particle Sizing Systems
75 Aero Camino Blvd., Suite B
Santa Barbara, CA 93117, USA
Telephone +1 727 846 0866
Fax +1 727 846 0865
http://www.pssnicomp.com
Surface Measurement Systems, Ltd.
5 Wharfside, Rosemont Road,
Alperton, Middlesex HA0 4PE
United Kingdom
Telephone +44 (0) 208 795 9400
Fax +44 (0) 208 795 9401
http://www.smsuk.co.uk/index.php
Sympatec GmbH
System-Partikel-Technik,
Am Pulverhaus 1
D-38678 Clausthal-Zellerfeld
Germany
Telephone +49 5323 717 0
http://www.sympatec.com/
8
General Program Schedule
Registration – Registration is outside of Citrus Ballroom in Prefunction Area
Saturday, May 13
(1800 – 1930) – Opening Informal Reception & Exhibition (Citrus Ballroom)
Sunday, May 14
(0800 – 0850) - Plenary 1 (Citrus Ballroom)
(0900 – 1230) – Technical Sessions: A1(Magnolia), B1 (Biscayne-Siesta), C1
(Jasmine), D1 (Oleander A), E1 (Oleander B), and F1 (Marathon-Cedar)
(1200 – 1400) – Luncheon/Exhibition (Citrus Ballroom)
(1400 – 1730) – Technical Sessions: A2 (Magnolia), G1 (Jasmine), H1
(Biscayne-Siesta), D2 (Oleander A), I1 (Oleander B), and J1 (Marathon-Cedar)
(1800 – 1930) – Poster Session (P1)/Reception/Exhibition (Citrus Ballroom)
Monday, May 15
(0800 – 0850) - Plenary 2 (Citrus Ballroom)
(0900 – 1230) – Technical Sessions: A3 (Magnolia), K1 (Marathon-Cedar), L1
(Biscayne-Siesta), D3 (Oleander A), E2 (Oleander B), and M1 (Jasmine)
(1230 – 1400) – Luncheon/Exhibition (Citrus Ballroom)
9
(1400 – 1730) – Technical Sessions: A4 (Magnolia), B2 (Biscayne-Siesta), C2
(Jasmine), D4 (Oleander A), I2 (Oleander B), and N1 (Marathon-Cedar)
(1800 – 1930) – Poster Session (P2)/Reception/Exhibition (Citrus Ballroom)
Tuesday, May 16
(0800 – 0850) - Plenary 3 (Citrus Ballroom)
(0900 – 1230) – Technical Sessions: A5 (Magnolia), G2 (Jasmine), O1
(Biscayne-Siesta), D5 (Oleander A), E3 (Oleander B), and J2 (Marathon-Cedar)
(1200 – 1400) – Luncheon/Exhibition (Grand Ballroom D)
(1400 – 1730) – Technical Sessions: A6 (Magnolia), K2 (Marathon-Cedar), H2
(Biscyane-Siesta), D6 (Oleander A), I3 (Oleander B), and M2 (Jasmine)
Conference Ends
10
Maps of Meeting Spaces
Contiguous meeting spaces at Wyndham. Conference activities use the Floral Ballroom on the
left, the Citrus Ballroom (center) through the Biscayne-Siesta room in the Key Rooms to the
right. Registration is outside of the Citrus Ballroom (center).
The Citrus Ballroom is the venue for all three Plenary Lectures, the luncheons, and the
receptions. The Marathon-Cedar and Biscayne-Siesta room to the right are used for some of
the technical break-out sessions.
All four parts of he Floral Ballroom are used throughout.
11
Technical Program
Technical Program
Sunday, May 14, 2006, Morning
Plenary 1 (Sunday 0800-0850, Citrus Ballroom)
Session Chair: Diane Burgess, University of Connecticut
0800 1. Francis Szoka, Jr.; Targetted bioresponsive nanolipid particles
Session A1 (Sunday 0900-1210, Magnolia) Nanoparticles & Hydrogels
Session Chair: Carlos Gamazo, Universidad de Navarra
0900 2. Hans Bäumler; Carrier for nanoparticles - Targeted delivery of water insoluble drugs
0925 3. Giulio Paciotti; Developing tumor targeted controlled release drug vectors on
colloidal gold nanoparticles
0950 4. Dan V.Goia; Preparation and characterization of electrostatically stabilized
dispersions of gold nanoparticles for medical and biological applications
1005 Break
1025 5. Arianna Friggeri; Low molecular weight hydrogelators as oral drug delivery systems
1040 6. Kazunari Akiyoshi; Nanogel engineering for polymeric drug delivery
1105 7. Michael Giersig; Cell growth and cell manipulation based on 2 and 3 dimensional
organization of nanosized materials of different morphology
1130 8. Julie Straub; Porous microparticle technology for imaging and drug delivery
1155 9. Satoshi Seino; Development of magnetic nanocarrier consisting of gold and iron
oxide for biomedical applications
1210 End of Session
Session B1 (Sunday, 0900-1200, Biscayne-Siesta) Emulsions
Session Chair: Tommy Horozov, University of Hull
0900 10. Irwin Gruverman; Keynote - Optimizing drug delivery - Efficient formulation
development and scaleable manufacturing methodology
0930 11. David Driscoll; Lipid injectable emulsions: Pharmacopeial and safety issues
0955 12. Maria-Teresa Celis; Droplet size distribution of liquid-liquid systems from UV-VIS
spectra
1010 Break
1030 13. Lynn Gold; Applications of Vitamin E based formulations
1055 14. Takasi Nisisako; Generation of monodisperse double emulsions in a planar
microfluidic network
1120 15. Robert Hoerr; Applying nanocomposite coatings on medical devices using
electronanospray
1145 16. Csilla Kollar; Silicone based controlled release dressing for accelerated proteolytic
debridement
1200 End of Session
12
Technical Program
Session C1 (Sunday, 0900-1230, Jasmine) Controlled Release
Session Chair: Nily Dan, Drexel University
0900 17. Heike Bunjes; Supercooled smectic nanoparticles – Development and
characterization of a novel drug delivery systems
0925 18. Brian G. Amsden; Sustained and active protein delivery from photo-cross-linked
biodegradable elastomer milli-cylinders
0950 19. Katarina Edsman; Pharmceutical application of catanionic complexes - sustained
drug release from gels
1015 Break
1030 20. Ponisseril Somasundaran; Modified polyacrylic and polysaccharide nanoparticles
for controlled extraction and release
1055 21. Dieter Trau; Enzymatic reactions in microcapsules
1110 22. Sabine Fischer; Bio goes Nano: The TNO Planomers® technology, developed to
improve commodity plastics by using nanotechnology, opens new possibilities for biomedical
materials like nanocomposites for tissue engineering or hybrid materials for drug delivery
1125 23. Irwin C.Jacobs; Development of formulations and equipment for spray drying of
high value active ingredients for the pharmaceutical industry
1150 24. Kenneth K. S.Lau; All-dry encapsulation of fine pharmaceutics for controlled drug
release
1205 25. Vince Rotello; Keynote - Drug, protein, and DNA delivery with
glutathione-mediated release using gold nanoparticles
1230 End of Session
Session D1 (Sunday, 0900-1200, Oleander A) Diagnostics
Session Chair: Todd Krauss, University of Rochester
0900 26. Shlomo Margel; Keynote - Synthesis and characterization of nano and micron-sized
particles of narrow size distribution for medical imagin applications
0930 27. Yuzhuo Li; Dynamic NMR characterization of nanoparticles for medical imaging
applications
0950 28. Terry Matsunaga; Perfluorocarbon nanobubbles as diagnostic and therapeutic agents
1010 Break
1030 29. Marc Herold; Molecularly imprinted nanoparticles for analytical and preparative
separation of amino acid derivatives
1045 30. Reyad Sawafta; Nanomagnetic particles in rapid diagnostics
1105 31. John Forsayeth; Real time visualization of nano-liposomal delivery into primate
brain by magnetic resonance imaging
1125 32. Jean-François Berret; Controlled clustering of superparamagnetic nanoparticles
using block copolymers : Design of new contrast agents for magnetic resonance imaging
1140 33. Karin Caldwell; Multilayered nanoparticles: Characterization and bioanalytical use
1200 End of Session
Session E1 (Sunday, 0900-1230, Oleander B) …Somes
Session Chair: Laurence Navailles, Centre de Recherche Paul Pascal, Bordeaux
13
Technical Program
0900 34. David Thompson; Keynote - Comparative performance of transfection complexes
derived from a family of bisvinyl ether cationic lipids
0940 35. Martin Caffrey; Lipidic cubic phases: Applications in membrane protein
crystallogenesis and in uptake and delivery
1010 Break
1030 36. Alexander Couzis; Spatially addressable protein arrays based on proteoliposome
self- assembly into microwells
1100 37. Daryl Drummond; Use of novel intraliposomal stabilization strategies for forming
highly stable and long circulating nanoliposome constructs for camptothecins and vinca
alkaloids
1125 38. Jan A.A.M. Kamps; Liposomes targeted to activated endothelial cells selectively
affect glomerulonephritis in mice
1140 39. Shinichi Kaneda; TRM-484 steroid included in long circulating cationic lipsosomes
actively targeting inflammatory tissues
1205 40. Dan Luo; DNA-based hydrogels, lipsosomes and nanobarcodes
1230 End of Session
Session F1 (Sunday 0900-1230, Marathon-Cedar) Particle Characterization
Session Chair: Frank Etzler, Boehringer-Ingelheim Pharmaceuticals
0900 41. P. Stephen Williams; Characterization of magnetic nanoparticles using quadrupole
magnetic field-flow fractionation
0930 42. Hélène Dihang ; Colloidal stability of emulsions and nanoparticles in pharmaceutics
0955 43. Frank M. Etzler; Particle size analysis: Compartive results from several techniques
1010 Break
1030 44. A.P. Tinke; Particle size and shape characterization of nano- and submicron
suspensions
1100 45. Natasha Starostina; AFM capabilities in characterization of particulate matter from
Angstoms to microns
1115 46. Mike Bogan; Femtosecond pulse vacuum-ultraviolet-free electron laser diffraction
scattering of polystyrene nanoparticles
1130 47. Chak K. Chan; Understanding the efflorescence of supersaturated droplets using
fluorescence spectroscopy
1200 48. Tim B. Van der Wood, Three dimensional characterization of pharmaceutical
powders by scanning white light interference microscopy
1215 49. Dietmar Lerche; Potential of microcapsules made from plant pollen for application
in chromatography
1230 End of Session
Sunday, May 14, 2006, Afternoon
Session A2 (Sunday, 1400-1730, Magnolia) Nanoparticles & Hydrogels
Session Chair: Hans Bäumler, Charité - Universitätsmedizin Berlin
14
Technical Program
1400 50. S. Iwamoto; Novel methods of producing nano- and microsized particles composed
of natural polyelectrolytes
1430 51. Andreas Taubert; Peptide and polymer assembly-controlled nanoparticle formation
1455 52. Kent Coulter; Development of nanoengineered platelets
1510 Break
1530 53. Esko Kauppinen; Gas-phase synthesis and coating of multifunctional nano- and
microparticles for drug delivery
1555 54. Yuichi Yamasaki; DNA condensation mechanism revealed under fluorescence
video-microscopy
1620 55. Andrew Loxley; Novel nanoparticle technologies for cost-effective, targeted,
non-systemic delivery of therapeutic agents
1635 56. Tamoaki Hino; Silk microspheres prepared by spray-drying of an aqueous system
1700 57. Igor Sokolov; Synthesis and applications of arrays of silica nanotubes
1715 58. Carlos Gamazo; Use of flagellin and mannosamine nanoparticles as bioadhesive
carriers for mucosal vaccination
1730 End of Session
Session G1 (Sunday, 1400-1700, Jasmine) Particle Toxicology
Session Chair: Roberta Brayner, Université Paris 7-Denis Diderot
1400 59. Vicki Colvin; Structure-function relationships of nanoparticles and their toxicity - A
general introduction to nanomaterials and their uses in medicine
1440 60. Hong Yang; Nanoparticle-induced biological responses: Effect of size, shape and
surface chemistry
1510 Break
1530 61. Daniel J. Watts; Phytotoxicity of some manufactured nanoparticles
1600 62. Janos Szebeni; Complement-mediated hypersensitivity reactions to nanoparticulate
drugs and solvents systems
1630 63. Natalia Varaksa; Aqueous dispersions of carbon nanotubes for biological testing and
applications
1645 64. Roberta Brayner; Toxicological impact studies based on Escherichia coli bacteria in
an ultrafine ZnO nanoparticles colloidal medium
1700 End of Session
Session H1 (Sunday, 1400-1725, Biscayne-Siesta) Photodynamic and EM Therapy
Session Chair: Ross W. Boyle, University of Hull
1400 65. Hubert van den Bergh; Keynote - Photodynamic therapy in the chorioallantoic
membrane model: Combination therapy using asprin enhances photodynamic selective drug
delivery and influence of the size of TCPP-loaded nanoparticles on phototoxicity
1430 66. Wei Chen; Nanoparticle self-lighting photodynamic therapy for cancer treatment
1455 67. Min Hu; Time-resolved spectroscopy study of the photothermal properties of gold
nanocages
1510 Break
1530 68. Gereon Huettmann; Laser irradiated gold nanoparticles: A new tool for selective
mainpulation of cells and biomolecules
15
Technical Program
1555 69. Naoto Oku; Angiogenic vessel-targeted cancer therapy
1620 70. Robert Ivkov ; Development of tumor targeting magnetic nanoparticles for cancer
therapy
1645 71. Cornelus F. van Nostrum; Methacrylamide-oligolactates as building blocks for
targeted biodegradable polymeric micelles to deliver photosensitizers
1700 72. Leanne B. Josefsen; Porphyrin-nanoparticle sensors for detecting cellular
response(s) to oxidative stress
1725 End of Session
Session D2 (Sunday, 1400-1715, Oleander A) Diagnostics
Session Chair: Yuzhou Li, Clarkson University
1400 73. Roger Leblanc; Keynote - Quantum dots as immunoassay probes
1430 74. Hedi Mattoussi; Development of FRET-based QD-bioconjugate sensors for
detecting enzymatic activity
1455 75. Detlef Müller-Schulte; Giant magnetic quantum dots as individually addressable
high sensitive optical bar codes for diagnostics and bioanalytics
1510 Break
1530 76. Yongxian Wang; Synthesis of ultra-stable bare CdS nanocrystals with strong
luminescence by hydrothermal synthesis
1545 77. Todd D. Krauss; Colloidal semiconductor quantum dots in selective labeling of
pathogenic bacteria
1610 78. Robert M. Tsikhudo; A generic approach to biomolecular functionality on gold and
silver nanoparticles
1635 79. David E. Cliffel; Epitope presentation on gold nanoparticles for immunoassay
development
1700 80. Volker Mailänder; Surface modification of particles enhances intracellular uptake
1715 End of Session
Session I1 (Sunday, 1400-1710, Oleander B) Micelles, Dendrimers & Conjugates
Session Chair: Michael Giersig, CAESAR Research Center, Bonn
1400 81. Vladimir Torchilin; Keynote - Polymeric micelles: Potential as pharmaceutical
nanocarriers
1440 82. Rex P. Hjelm; Self-assembly of surfactant aided delivery systems
1510 Break
1530 83. Afsaneh Lavasanifar; Polymeric micelles for tumor targeted delivery of
P-glycoprotein inhibitors
1555 84. Christine Allen; Engineering copolymer materials and micelles for targeted delivery
of hydrophobic drugs
1620 85. Francois Ravenelle; Nanodelivery using block copolymers: A Propofol solution
1645 86. Kent Jørgensen; Tumor triggered activation and release of drugs from lipid based
drug and prodrug nanocarriers
1710 End of Session
16
Technical Program
Session J1 (Sunday, 1400-1730, Marathon-Cedar) Gene Delivery
Session Chair: David Thompson, Purdue University
1400 87. Mizuo Maeda; Non-crosslinking aggregation of DNA-carrying nanoparticles for
gene diagnosis
1430 88. Jon Preece; Gluatathione degradable and pH modulatable polycation/DNA
nanoplexes for gene delivery
1455 89. Rumiana Koynova; Lipid phase control of DNA delivery
1510 Break
1530 90. Diane Burgess; Gene delivery and quantum dot assisted intracellular trafficking
1600 91. Wee Beng Tan; Multifunctional nanoparticles for imaging assisted gene therapy
1630 92. Roberta Carbone; Cluster assembled nanostructured TiO2 film mediates efficient
and safe retroviral gene transduction in primary adult human melanocytes for ex-vivo gene
therapy
1645 93. Harald Petry; JC virus-like particles: Size dependent in vitro DNA packaging and
gene delivery
1700 94. Pauline Li ; Amphiphilic core-shell nanoparticles with poly(ethyleneimine) shells as
potential gene delivery carriers
1730 End of Session
Sunday, May 14, 2006, Evening
Poster Session P1 (Sunday, 1800-1930, Citrus Ballroom)
Session Chair: John Texter, Eastern Michigan University
General Papers
274. Venisetty R. Kumar; Pharmacokinetics and antileishmanial activity of mannose grafted
amphotericin B lipid nanospheres
275. Venisetty R. Kumar; Formulation and quality control of gastroretentive tablets of
ranitidine hydrochloride
276. Kevin A. Heitfeld; Smart membranes for flavor delivery
277. Ganesan Alasundaram; Increased osteoblast functions on Ti nanopatterned with peptides
278. Daniel J. Burnett; Correlation of polymer energetics and drug release rates
279. Daniel J. Burnett; Investigating the kinetics of moisture-induced crystallization of
amorphous lactose
Nanoparticles & Hydrogels
280. Ginger Denison Rothrock; Scalable fabrication of monodisperse, shape-specific organic
nanoparticles for use as delivery vectors
281. Virginia Saez-Martinez; Chemical functionalization of poly(nitrophenyl
acrylate-co-methacrylamide) microgels with pH-sensitive groups and a targeting ligand
282. Chul Ho Park; Nanoparticle preparation of ?–lipoic acid susceptible to polymerization
283. Boon Sing Ng; Synthesis, functionalization and transport properties of mesostructured
particles
17
Technical Program
284. Anika A. Odukale; Molecularly imprinted hydrogel microspheres for phosphate removal
285. Michihiro Nakamura ; Synthesis and characterization of silica nanoparticles with high
fluorescence
286. Nobuyuki Morimoto; Enzymatic synthesis and characterization of nanogels by
self-assembly of hydrophobized poly(L-lysine)-amylose conjugates
287. Yoshitake Masuda; Invited Poster - I. Control of crystallization for medical applications:
I - Control of nucleation and growth of magnetite particles for cancer heat immunotherapy; II
- Spherical particle-assembly by two-solution method for drug delivery system
288. Eun-Jung Kim; Solid lipid nanoparticles to overcome multi-drug resistence in cancer
289. Liisa T. Kuhn; Effect of nano-sizing calcium phowphate/cisplatin coordination
complexes on in vitro drug release
290. Jianhua Hu; Biodegradable polymer aggregates prepared by amphiphilic
poly(hydroxyethyl aspartamide-co-propyl aspartamide) grafted with (lactide) for drug
deliverly
Diagnostics
291. Sudip Nath; Synthesis, characterization and localized surface plasmon resonance study
of silver organosol
292. Wee Beng Tan; Water-soluble fluorescent LaF3:Ln3+ nanocrystals for bio-applications
293. Igor Sokolov; Fluorescent silica beads for detection of cervical cancer
294. Jaswinder Sharma; DNA-templated self-assembly of two dimensional and periodical
gold nanoparticle arrays
295. Anna Galperin; Synthesis and characterization of polymeric microspheres of narrow size
distribution containing iodine for x-ray imaging applications
296. E. Sócrates. T. Egito; Incorporation of magnetic particles in polymer systems of xylan
297. E. Sócrates. T. Egito; Magnetite particle dissolution at gastric pH
298. Detlef Müller-Schulte; Composite thermoresponsive microgel core decorated with
magnetic nanoparticles
299. Detlef Müller-Schulte; Magnetic nanoparticles – Polyelectrolyte interaction: A layered
approach for biomedical application
300. Arnold J. Kell; Functionalized superparamaganetic nanoparticles as pathogen capture
probes
301. Marc Herold; Core-shell nanoparticles with covalently linked TNF for cell signalling
investigations
302. Marc Herold; Novel nanoparticles with activated ester surface prepared by emulsion
polymerization of polymerizable surfactants
Inhalation
303. Janne Raula ; Production of novel multicomponent pharmaceutical nano and
microparticles with an aerosol flow reactor method
304. Philippe Rogueda ; Size and concentration monitoring of HFA suspensions
305. David P. Brown, Dispersion of novel inhalation drug powders with nanocrystalline
L-leucine coating
Characterization
18
Technical Program
306. Andrew Parker; Quantitative hardness and surface characterization by atomic force
microscopy for use in early stage screening of pharmaceutical formulations
307. Ben Lich; Particle size distribution characterization of sub-micron suspensions using
electron microscopy
308. Dietmar Lerche ; Methods for characterization of micro- and nano-sized particles and
capsules
309. Sarah Hook; Characterizing bicontinuous cubic nanoparticles by cryo field emission
scanning electron microscopy
310. Wolfgang Fritzsche; Characterization of metal deposition on nanoparticles at single
particle level
311. Lizandra Castro; Adhesion forces between hybrid colloidal particles and concanavalin A
312. Amber Clausi; Investigation of the particle size distribution and zeta potential of
aluminum hydroxide adjuvant following freeze drying and freeze thawing
Super Critical Fluid Processing
313. A.R. Sampaio de Sousa; Incorporation of hydrophilic compounds in solid lipid particles
using supercritical fluid technology
314. Ana Rita C. Duarte; Acetazolamide controlled release from microparticles prepared by
SAS
Particle Toxicology
315. Giovana R. Tofoli; Pharmacological and histological evaluation of
hydroxypropyl—cyclodextrin-bupivacaine inclusion complex
316. Tammy Oreskovic; In vitro testing of vascular smooth muscle cells exposed to
unmodified multiwalled carbon nanotubes
317. Regine Hedderich; NanoCare - Chances and risks of manomaterials
Monday, May 15, 2006, Morning
Plenary 2 (Monday 0800-0850, Citrus Ballroom)
Session Chair: Shlomo Margel, Bar Ilan University
0800 95. Sandy Asher; Particle Array Sensors for Biochemical Diagnostics
Session A3 (Monday, 0900-1210, Magnolia) Nanoparticles & Hydrogels
Session Chair: Eugene Goldberg, University of Florida
0900 96. Wolfgang Parak; Characterization and biological application of colloidal
nanoparticles
0925 97. Laurie Gower; Biomimetic processing methods for organic-inorganic particles
0950 98. Xinqiao Jia; Hyaluronan-based hydrogel microspheres for vocal fold regeneration
1005 Break
1025 99. Anna Musyanovych; Miniemulsions for biomedical applications
19
Technical Program
1040 100. Gershon Golomb; Targeting monocytes by nano-particulated formulations and
vascular healing
1105 101. Ron Boch; Ocular drug delivery using lipid, polymer and suspension formulations
1130 102. Sandy Rosenthal; Imaging cell surface receptors with ligand conjugated
nanocrystals
1155 103. Zhengmao Li; Oral insulin delivery with biodegradable and biocompatible
nanocapsules
1210 End of Session
Session K1 (Monday, 0900-1230, Marathon-Cedar) Inhalation & Aerosols
Session Chair: Hans Leuenberger, Institute of Pharmaceutical Technology, Basel
0900 104. Philippe Rogueda; Keynote - The nanoscale in inhalation delivery
0930 105. Uday Kompella; Particulate systems for pulmonary drug delivery: Safety,
sustained release, and efficacy
0955 106. Amy M. Waligorski; An ingredient-specific method for particle size
characterization of corticosteroid nasal sprays
1010 Break
1030 107. Mark Bumiller; A study of liquid properties and droplet size distributions of some
common nasal decongestant spray formulations
1045 108. James R. Benson; New polymer enables zero-order release of drugs
1110 109. Jim Blanchard; Advances in liquid aerosol delivery systems
1135 110. Robert Cook; Embracing particle engineering for inhalation drug products
1200 111. Jimmy Yun; Design and production of ultrafine active pharmaceutical ingredients
under high gravity environment
1230 End of Session
Session L1 (Monday, 0900-1200, Biscayne-Siesta) Cancer Targetting
Session Chair: Afsaneh Lavasanifar, University of Alberta
0900 112. X.Y. (Shirley) Wu; Keynote - New polymer-lipid hybrid nanoparticles for
enhanced anticancer drug delivery
0940 113. Kathleen F. Pirollo; A versatile tumor targeting nanoadelivery platform for cancer
diagnosis and therapy
1010 Break
1030 114. Iris V. Enriquez; DNA mesospheres as drug delivery vehicles for localized cancer
chemotherapy
1045 115. P. Low; Ligand-mediated targeting of nanoparticles and low molecular weight
drugs to cancer cells and inflammatory immune cells
1110 116. Balaji Panchapakesan; Single wall carbon nanotube nanobomb agents for cancer
therapeutics
1135 117. Bob (RJ) Lee, Folate receptor-targeted liposomes and nanoparticles for caner
therapy
1200 End of Session
Session D3 (Monday, 0900-1230, Oleander A) Diagnostics
20
Technical Program
Session Chair: Wolfgang Fritzsche, Institute for Physical High Technology, Jena
0900 118. Brigitte von Rechenberg; Keynote - Superparamagnetic iron oxide particles as a
drug delivery system for in vivo application in the joint
0930 119. Taeghwan Hyeon; Generalized and large-scale synthesis of monodisperse
nanocrystals of ferrites and oxides and their applications as MRI contrast agents and in drug
delivery
0955 120. Paul S. Russo ; Silica-polypeptide composite particles
1010 Break
1030 121. Mohammad S. Uddin; Surface functionalized nano-magnetic particles for
adsorprtion/desorption of biomolecules
1045 122. Marc Porter, Strategies for the design and readout of ultrahigh density
immunodiagnostic platforms
1110 123. Andreas Hütten; Magnetic nanoparticles: Aapplications beyond data storage
1135 124. Shy Chyi Wuang; Functionalization of magnetic nanoparticles with biomolecules
1150 125. Dave Thomas; Particle population classification by micro-flow imaging
1205 126. Nguyen TK Thanh; Development of magnetic nanoparticles for biomedical
application
1230 End of Session
Session E2 (Monday, 0900-1200, Oleander B) …Somes
Session Chair: Martin Caffrey, University of Limerick
0900 127. Gilbert Grant; Keynote - Liposomal bupivacaine: An ultra-long acting local
anesthetic
0940 128. Indranil Nandi; Application of lipid based drug delivery system for water insoluble
drugs
1010 Break
1030 129. Kenji Kono; Preparation of thermosensitive liposomes by use of amphiphilic block
copolymers and their application to anticancer drug delivery
1100 130. Terrence Scott; PROMAXX microsphere drug delivery technology
1130 131. Laurence Navailles; Dislocation loop mediated smectic melting
1200 End of Session
Session M1 (Monday, 0900-1230, Jasmine) SCF Processing
Session Chair: Paolo Caliceti, Universty of Padua
0900 132. Keith Johnston; Particle engineering and formulation for enhanced bioavailability
of poorly water soluble drugs
0935 133. Steve Howdle; Particles for drug delivery and medical applications: A supercritical
approach
1000 134. Jennifer A. Green; Investigation into particle size variations with process
parameters using Nektar supercritical fluid technology
1015 Break
1035 135. Boris Shekunov; New particle technologies for drug delivery
21
Technical Program
1105 136. Ram B. Gupta; Formation of drug nanoparticles and microparticles using
supercritical CO2
1135 137. Bob Sievers; Drug delivery applications of particle technology using CAN-BD
processing
1205 138. Sung-Joo Hwang; Nanoparticles for enhanced solubility and bioavailability of
poorly-water soluble drugs using supercritical fluid technology
1230 End of Session
Monday, May 15, 2006, Afternoon
Session A4 (Monday, 1400-1730, Magnolia) Nanoparticles & Hydrogels
Chair: Renato Camata, University of Alabama at Birmingham
1400 139. Paul Braun; Double direct templating of periodically nanostructured ZnS hollow
microspheres
1430 140. Takashi Miyata; Signal biomolecule-responsive gels
1455 141. Jonghwi Lee; Preparation of polymer/drug nano- and micro-particles by
electrospraying
1510 Break
1530 142. Bruno G. De Geest; Polyelectrolyte microcapsules for biomedical applications
1545 143. James Talton; Oral nanoparticle deivery
1610 144. Eugene Goldberg; Drug-loaded protein and DNA nano-meso-microspheres for
non-systemic intratumorial chemotherapy
1635 145. Chang Chun Wang; Preparation of magnetic polymeric microspheres for
application in biomedical fields
1700 146. Aravind Chakrapani; Fabrication of biodegradable polymer microdevices for
controlled drug delivery systems
1715 End of Session
Session B2 (Monday, 1400-1720, Biscayne-Siesta) Emulsions - Particles from Emulsions
Session Chair: David Driscoll, Harvard University
1400 147. Ozgen Ozer; W/O/W multiple emulsions containing nitroimidazole derivatives for
vaginal application
1425 148. Tommy Horozov; Mechanisms of emulsion stabilization by colloidal particles
1450 149. Katrin Ebert; Preparation of biodegradable nanoparticles by a membrane based
process
1515 Break
1535 150. Hidekazu Yoshizawa; New functions of grafted-polymer layers of core/corona
polymer nanospheres in bioseparation
1550 151. Dietmar Lerche; Rapid stability testing and shelf life determination of concentrated
emulsions
1615 152. Christophe J. Barbé; Ceramispheres: Controlled release from sol-gel micro and
nanoparticles
1630 153. Wei Lu; Double emulsion based synthesis of pegylated nanoparticles for brain
delivery
22
Technical Program
1655 154. Yujie Dai ; Colloidal emulsion aphrons: Structure, principles, properties and
applications
1720 End of Session
Session C2 (Monday, 1400-1730, Jasmine) Controlled Release
Session Chair: Heike Bunjes, Friedrich Schiller University, Jena
1400 155. Michael Pishko; Keynote - Encapsulation of drug nanoparticles in self-assembled
macromolecular nanoshells
1430 156. Nily Dan; Effect of drug characteristics on the degradation mechanism and drug
release rate from biodegradable polymer matrices
1455 157. Sheng Qi; Investigation into the influence of fatty acid purity on the drug release
behavior of taste-masking fatty acid microsphers
1510 Break
1530 158. Jacco Eversdijk; Functional microencapsulation using hybrid materials
1545 159. Hideki Ichikawa; Acrylate-based nanogels as microcapsular membrane
components for peptide delivery
1610 160. Detlef Müller-Schulte; Thermosensitive magnetic nano- and microcarriers as
contactless controllable drug carriers and tools
1635 161. Peter Markland; Microparticle formulation development - Considerations from
bench top to clinical manufacturing
1700 162. Rick Rehrig; Vibrating nozzle processing in industrial microencapsulation
1715 163. Tinneke Van Thienen; On the synthesis and characterization of biodegradable
dextran nanogels with tunable degradation properties
1730 End of Session
Session D4 (Monday, 1400-1720, Oleander A) Diagnostics
Session Chair, Paul Russo, Louisiana State University
1400 164. Shawn P. Mulvaney; Fluidic force discrimination assays in complex media
1430 165. Geir Fonnum; Magnetic beads used in sample preparation for mass spectrometry
1500 166. Roel Wirix-Speetjens; Magneto-resistive immunosensors: Sensitivity enhancement
by active guiding of superparamagnetic particles
1515 Break
1535 167. Wing Cheung Mak; Encapsulated microcrystalline particles as label systems for
diagnostics
1550 168. Wolfgang Fritzsche; Chip-based molecular diagnostics using metal nanoparticles
1620 169. Dense F.S. Petri; Hybrid particles as substrates for biotargets and metallic ions
1635 170. Heinrich Haas; Assembly and in-vivo tracking of nanoparticulate carriers for
neo-vascular targeting
1650 171. Swadeshmukul Santra; Tuning of luminescence intensity of manganese doped
cadmium sulfide quantum dots by controlling surface passivation
1705 172. Matthias Frank; Single-particle bioaerosol mass spectrometry for medical and
biochemical diagnostics and analysis
1720 End of Session
23
Technical Program
Session I2 (Monday, 1400-1730, Oleander B) Micelles, Dendrimers & Conjugates
Session Chair: Sonke Svenson, Dendritic Nanotechnologies
1400 173. A.T. (Sandy) Florence; Keynote - Dendrimers, dendrons, dendrisomes and
dendriplexes as carriers in drug and gene delivery
1440 174. Sonke Svenson; Dendrimers: A platform for custom-designed drug delivery
1510 Break
1530 175. Thor Nilsen; What constitutes a particle? Assembly of 30-500 nm dendritic
(fractal) hyperpolymers via sequence recognition enabled polymers
1600 176. Victor Lin; Functionalized mesoporous silica nanoparticles for gene transfer,
intracellular controlled release, and biosensor applications
1630 177. Joseph Backer; A standardized procedure for derivatization of nanoparticles with
functionally active proteins
1700 178. Tao L. Lowe; Branched nanoparticles for drug delivery across the blood brain
barrier
1730 End of Session
Session N1 (Monday, 1400-1700, Marathon-Cedar) Suspensions and Dispersions
Session Chair: Mark Bumiller, Malvern Instruments
1400 179. Rainer H. Müller; Keynote - Nanosuspensions for the delivery of poorly soluble
drugs - State of art and latest developments
1440 180. Ingrid Fischbach; Nanosuspensions of poorly soluble active ingredients
1510 Break
1530 181. Ingo Leubner; Size control of nanoparticles in continuous crystallizations
1545 182. Hemant Joshi ; Applications of nanotechnology in the pharma industry – An
overview
1615 183. Christian Johansson; Electrostatic interacations between lysozyme and poly(acrylic
acid) microgel particles
1630 184. Maria-Teresa Celis; Use of particles as emulsion and foam stabilizers
1700 End of Session
Monday, May 15, 2006, Evening
Poster Session P2 (Monday, 1800-1930, Citrus Ballroom)
Session Chair: John Texter, Eastern Michigan University
General Papers
320. Shy Chyi Wuang; Surface functionalization of magnetic nanoparticles via
surface-initiated atom-transfer radical polymerization (ATRP)
321. Krassimir P. Velikov; Colloidal delivery systems for functional foods
322. Alex I. Smirnov; Template-assisted self-assembly of polymerizable lipid nanotubes
323. Eik Leupold; The uptake mechanism of an APOE-derived peptide depends on its
aggregational state
24
Technical Program
324. Daniel J. Burnett; Quantifying low levels of amorphous content using vapor sorption
techniques
325. Daniel J. Burnett; Investigating the effects of protein concentration on the glass transition
behavior of lyophilized protein-sugar formulations
Nanoparticles & Hydrogels
326. Meike Harms; Surface modified solid liIpid nanoparticles
327. Jessica Hain; Hybrid microgel particles with zinc sulfide inclusions
328. Larken E. Euliss; Exploiting emerging techniques in imprint lithobraphy to make highly
uniform, shape-specific drugs, imaging agents, and nano-carriers
329. Nelly Fransén; Development and characterization of interactive mixtures with a fine
particulate, mucoadhesive carrier for nasal drug delivery
330. Bruno G. De Geest; Monodisperse microgel synthesis inside microfluidic devices
331. Jerald W. Darlington; Modified nano-bentinite anit-viral activity against the herpes
simples virus type 1, rhinovirus type 37, and rotovirus
332. José F. Almeida; Novel crosslinked chitosan and dextran gels as drug delivery systems
333. Christina A. Bauer; Silica nanoparticle formation in confined environments via
biomimetic catalysis
334. Jean-Francois Berret; Nanoparticle-polymer complexation electrostatic self-assembly as
a route to stable dispersions of hybrid nanocolloids
335. Etienne Duguet; One-step synthesis of spinel iron oxide-based core-corona nanoparticles
for in vivo applications
Photodynamic & EM Therapy
336. Ji-Hun Yu; Fabrication and characterization of SiO2 and MgO coated Fe2O3
nanoparticles for hyperthermia applications
337. Sang-Eun Park; Preparation of gold nanocomposites with dielectric magnetic cores for
targeted photothermal therapy
Diagnostics
338. Jaswinder Sharma; DNA-templated self-assembly of two dimensional and periodical
gold nanoparticle arrays
339. Sofia Martins; Detection of hybridization reactions on microparticles by template
dependent extension
340. Roberta Brayner; Formation of hybrid nanoparticle-alginate microcapsules for
bio-detection applications
341. Angelika Müller; Magnetic nanoparticle-loaded erythrocytes as magnetic resonance
imaging contrast agents
342. Beata Chertok; Magnetic nanoparticles for possible simultaneous MR imaging and drug
therapy of brain tumors
343. Katarzyna Derwinska; Hydrogels and nanoparticles in microarrays for food control
344. Maciej Dybiec; Protein microarrays and spatially resolved photoluminescence in
bio-conjugated quantum dots-probes for early cancer detection
25
Technical Program
345. Karsten Wegner; Production of biocompatible films by controlled gas-phase synthesis
and deposition of nanoparticles
346. Sang Im Park; Synthesis of magnetic nanoparticles by thermal decomposition and
biocompatibility
Gene Delivery
347. Tomohiro Asai, Gene silencing of mutant K-ras mediated by polycation liposome
348. Ravil A. Sitdikov, Amperometric immunosensor based on highly dipsersed graphite
microparticles for influenza virus detection
Controlled Release
349. Divey Saini; Characterization of REP 2006 antiviral drug and drug delivery system for
small animal models
350. Janet R. Wendorf; A practical approach to the use of nanoparticles for vaccine delivery
351. Hulda Shaidi Swai; Evaluation of nanoencapsulation performed by spray drying
technique for the delivery of Tuberculosis drugs (ATD)
352. Edith C. Rojas; Double carrier systems as novel drug delivery vehicles
353. Sheng Qi; Investigation into using spray chilled Gelucire 50/13 microspheres as carriers
for poorly soluble drugs
354. Sara Ponce; Long-term study of EPO-secreting myoblasts entrapped in microcapsules
elaborated with five different commercial alginates
355. Jubo Liu; In vivo fate of the micelle forming block copolymer poly(ethylene
glycol-block-caprolactone) in mice following intravenous administration
356. Yongwoo Lee; Trehalose bearing polymeric particles: Sorption induced hydrolytic
degradation of pesticides and chemical agents
357. Bum Gil Kim; Biodegradable nanoparticles for vaccine delivery systems
358. Jae-Eun Jung; Effective stabilization of bioactive ingredients for long-terrm storage
using W/O/W encapsulation and buffering layer
359. E Sócrates. T. Egito; Development of a new multiparticulate system for colon controlled
drug delivery
360. E Sócrates. T. Egito; Sodium diclofenac incorporation into xylan microcapsules for
colonic drug delivery
361. Masakazu Furuta; Drug release from nanoparticles made of radiation-crosslinked elastin
model polypeptides
...Somes
362. Per Wessman; Melittin-lipid interactions: A comparison between liposomes and
polymer-stabilized nanodiscs
363. Guifang Zhang; Nimodipine-nanoliposomes: Preparation, characterization and
pharmacokinetics in rat
364. Maria R. Toler; Determining the dispersion behavior of formulated Bulk drug using light
diffraction analysis
26
Technical Program
365. Jasna Urbanija; Giant phospholipid vesicles as a possible system for studying
interactions of membranes with antibodies
Tuesday, May 16, 2006, Morning
Plenary 3 (Tuesday 0800-0850, Citrus Ballroom)
Session Chair: Joe DeSimone, University of North Carolina
0800 185. Heinrich Hofmann; Superparamagnetic particles for diagnostic and Therapeutic
applications
Session A5 (Tuesday, 0900-1230, Magnolia) Nanoparticles & Hydrogels
Session Chair: Robert Pelton, McMaster University
0900 186. Joe DeSimone; Keynote - Exploiting emerging techniques in imprint lithography to
make highly uniform, shape-specific drugs, imaging agents and nano-carriers
0930 187. Jim Lee; Molecular spring assemblies of nanoparticles and nanowires
0955 188. Renato P. Camata; Development of nanoengineered calcium phosphate-based
particulates for gene delivery
1010 Break
1030 189. Joseph F. Bringley; Precision assembly of multicomponent nanoparticulate
colloids
1045 190. Yiguang Jin; The Self-assembly behavior of the cholesteryl derivatives of acyclovir
and he preparation of self-assembled nanoparticles
1100 191. Neal K. Vail ; Targeted nanoparticles for bone therapies
1125 192. Shannon Morrison; Iron nanoparticles as magnetic carriers
1150 193. Stan Farnsworth; Broad-band efficacy determination for discrete silver
nanoparticles
1205 194. Cory Berkland; Nanoclusters as a unique drug delivery platform
1230 End of Session
Session G2 (Tuesday, 0900-1200, Jasmine) Particle Toxicology
Session Chair: Janos Szebeni, Semmelweis University, Hungarian Academy of Sciences
0900 195. Vicki Stone; Keynote - The cellular and molecular toxicity of low solubility
nanoparticles
0940 196. Robert DeLong; Formulation processes and characterization of DNA and siRNA
nanoparticles
1010 Break
1030 197. Tridib K. Bhowmick; Physicochemical analysis and effects on yeast cells of a
particulate traditional Indian medicine, jasada bhasma
1045 198. Gan-Moog Chow; Physical properties and cytotoxicity of inorganic nanoparticles
for biomedical applications
1110 199. Robert Hurt; Green nanotechnology through collaborative research on mechanisms
of nanomaterial toxicity
1135 200. James L. McGrath; Nanoparticle interactions with the cytoskeleton
27
Technical Program
1200 End of Session
Session O1 (Tuesday, 0900-1145, Biscayne-Siesta) Vaccine Delivery
Session Chair: Bill Turnell, Medivas
0900 201. Gary Fujii; Keynote - Nanoparticle based vaccine design: The VesiVax system
0940 202. Thomas Luby; Clinical development of a therapeutic microparticle formulation
1010 Break
1030 203. Ana M. Carmona-Ribeiro; Biomimetic particles for vaccine design
1045 204. Thierry Delair; Design of synthetic colloidal antigen carriers for vaccine purposes
1115 205. Balaji Narasimhan; Novel injectable biomaterials for protein and vaccine delivery
1145 End of Session
Session D5 (Tuesday, 0900-1230, Oleander A) Diagnostics
Session Chair: J. Manuel Perez, University of Central Florida
0900 206. Orlin D. Velev; Keynote - Colloidal assembly extended into the biomaterials
domain: Composite coatings and membranes from live cells
0930 207. Yi Lu; Genetic control of nanoparticle assembly and its application in colorimetric
sensing
0955 208. Robert I. MacCuspie; Development of a multiplex peptide nanotube-based
pathogen assay
1010 Break
1030 209. Frank van Veggel; Surface modified lanthanide doped nanoparticles as new robust
biolabels
1045 210. Tania Q. Vu ; Nanoparticle quantum dots for targeted neuromodulation
1100 211. Yvon Durant; Targeted and functional nanoparticles for biomedical diagnostics
1125 212. Femke De Theije; Detection of drugs of abuse using a magnetic biosensor
1150 213. K. Bonroy; Sensing substrates modified with gold nanoparticle films
1205 214. Beth Goins; Radiolabeled lipid nanoparticles for imaging and radionuclide therapy
1230 End of Session
Session E3 (Tuesday, 0900-1200, Oleander B) …Somes
Session Chair: Ijeoma F. Uchegbu, University of Strathclyde
0900 215. David Needham; Keynote - A new paradigm for local drug delivery: Temperature
triggered release liposomes for anti-tumor applications
0940 216. David Sheff; Retrograde delivery of bacterial toxins passes through the recycling
endosome of mammalian cells
1010 Break
1030 217. Ramin Darvari; Polyelectrolyte self-assembly to modify surface properties of
PROMAXX insulin microspheres
1045 218. Dian R. Arifin; Polymersome encapsulated hemoglobin (PEH): A novel type of
oxygen carrier
1100 219. Krzysztof J. Dziewiszek; Liposomal delivery of all-trans-retinoic acid: Challenges
and results
28
Technical Program
1130 220. Hiroyuki Nakamura; Transferrin-loaded nido-carborane liposomes: Synthesis and
intracellular targeting to solid tumors for boron neutron capture therapy
1200 End of Session
Session J2 (Tuesday, 0900-1230, Marathon-Cedar) Gene Delivery
Session Chair: Jon Preece, University of Birmingham
0900 221. Larry Brown; Keynote - Nucleic acid microspheres for Type 1 diabetes
intervention
0940 222. Sean Sullivan; Development of nanotransfection complexes for systemic treatment
of cancer
1010 Break
1030 223. Sarah W. Kamau; Enhancement of the efficiency of non-viral gene delivery by
application of pulsed magnetic field
1045 224. David Thompson; Synthesis, characterization & triggered dethreading of
cyclodextrin-polyethylene glycol polyrotaxanes bearing ceavable “click” endcaps
1115 225. Sang-Kyung Lee; Targeted neuronal delivery of a single antiviral siRNA protects
mice against encephalitis caused by two distinct flaviviruses
1130 226. Chong-Su Cho; Receptor-mediated gene delivery using chitosan derivatives in
vitro and in vivo
1200 227. Lou Zumstein; Nanoparticle mediated delivery of tumor suppressor genes
1230 End of Session
Tuesday, May 16, 2006, Morning
Session A6 (Tuesday, 1400-1730, Magnolia) Nanoparticles & Hydrogels
Session Chair: Shannon Morrison, Virginia Commonwealth University
1400 228. Robert Pelton ; Glucose sensing microgels
1425 229. Peter Burkhard; Peptide nanoparticles for medical applications: Novel drug
targeting, delivery and vaccination strategies
1450 230. James Worden; Preparation of monofunctional gold nanoparticle-dendrimer
(pamam) conjugates by covalent approach
1505 Break
1525 231. Omid Veiseh; Chlorotoxin-bound superparamagnetic nanoparticles for brain tumor
diagnosis and therapeutics
1550 232. L. Juillerat-Jeanneret; Functionalization of nanopaticles for disease detection and
targeted drug delivery
1615 233. Hsien-Hsin Tung; Precipitation of an amorphous pharmaceutical solid
1630 234. Monique Smaïhi ; Semicarbazide functionalized silicate nanoparticles for peptide
ligation
1645 235. Reynolds A. Frimpong; Integration of magnetic nanoparticles into temperature
responsive hydrogel systems
1700 236. Brij Moudgil; Keynote - Engineered nanoparticulate systems for biomedical
applications
1730 End of Session
29
Technical Program
Session K2 (Tuesday, 1400-1725, Marathon-Cedar) Inhalation & Aerosols
Session Chair: Philippe Rogueda, AstraZeneca
1400 237. David L. Gardner; Keynote - Factors to consider in developing a dry powder
inhaler
1430 238. Andrew Martin; Particle fabrication for aerosol drug delivery
1455 239. Philippe Rogueda; Particle aggregation in therapeutic aerosols
1510 Break
1530 240. Michael Lipp; An overview of Alkermes AIR® dry powder particle formulation
technology for pulmonary delivery
1555 241. Matti Murtomaa; Electrostatic measurement methods in pharmaceutical aerosols
1620 242. Niklas Sandler; Powder surface image analysis in screening of functional bulk
properties of pharmaceutical particles
1645 243. Jimmy Yun; Novel porous hollow silica nanoparticles for drug/pesticide release
control
1700 244. Hans Leuenberger; FDA’S pharmaceutical CGMPS for the 21st century; Do we
need a special research initiative in pharmaceutical powder particle technology to comply
with the new requirements?
1725 End of Session
Session H2 (Tuesday, 1400-1705, Biscayne-Siesta) Photodynamic and EM Therapy
Session Chair: Hubert van den Bergh, Swiss Federale Institute of Technology, Lausanne and
Alfred Fahr, University of Jena
1400 245. Alfred Fahr; Liposomal formulations of a photosensizer: Green light for an old
substance
1430 246. Gemunu Happawana; Use of a scattering element and direct deionized water
cooling in high power semiconductor diode lasers to enhance the beam divergence and
performance for use in photodynamic therapy (PDT)
1500 247. Dongling Ma; Developing multifunctional nano-architectures: Luminescent and
superparamagnetic
1515 Break
1535 248. Gloria J. Kim; Cancer nanotechnology: Designing multifunctinal nanostructures
for targetting tumor cells and vasculatures
1605 249. Sebastien Vasseur; La0.75Sr0.25MnO3-based magnetic nanoparticles as potential
heat mediators in oncology
1620 250. Ross W. Boyle; Photosensitiser-macromolecule conjugates for targeted
photodynamic therapy
1650 251. Jun Shao; Indocyanine green-loaded nanoparticulate delivery systems for
superficial tumor diagnosis and treatment
1705 End of Session
Session D6 (Tuesday, 1400-1730, Oleander A) Diagnostics
Session Chair: Kui Yu, Steacie Institute for Molecular Sciences, Ottawa
30
Technical Program
1400 252. J. Manuel Perez; Keynote - Magnetic biosensors in biodiagnostics
1430 253. Xiaohu Gao; Multifunctional quantum dots for molecular imaging and therapeutics
1455 254. Robert Nooney; Plasmon-enhanced fluorescence of dyes attached to
polyelectrolyte coated metal nanoparticles
1510 Break
1530 255. Tao Liu; Nano-biosensor for detection of disease
1545 256. Hilde Jans; Biofunctionalization of water-dispersible gold nanoparticles
1600 257. Stephane Legastelois; A new particle-based immunoassay that depends on the
quantitative detection of magnetic particles
1625 258. Jin Zhang; Cancer biomarker detection based on photoluminescence of
semiconductor quantum dots and SERS of metal nanostructures
1650 259. Dave Thomas; Particle population classification by micro-flow imaging
1705 260. Kui Yu; Development of colloidal semiconductor nanocrystals as bio-imaging
probes
1730 End of Session
Session I3 (Tuesday, 1400-1730, Oleander B) Micelles, Dendrimers & Conjugates
Session Chair: Tao L. Lowe, Penn State University
1400 261. Ijeoma F. Uchegbu; Keynote - Nanomedicines for efficient drug and gene delivery
1440 262. Bill Turnell; Novel polymer technology for the delivery of biological
macromolecules
1510 Break
1530 263. Robert W. Lee; Micellar nanoparticles
1600 264. Martin Woodle; Tissue targeted nanoparticles for systemic delivery of nucleic acid
agents enables siRNA therapeutics
1630 265. Chun Li; Poly-L-glutamic acid as a building block for nanomedicine: From
theapeutics to multimodality diagnostics
1700 266. Meike Harms; Formation of reverse micellar type versus surface modified solid
lipid nanoparticles
1730 End of Session
Session M2 (Tuesday, 1400-1730, Jasmine) SCF Processing
Session Chair: Ram B. Gupta, Auburn University
1400 267. Neil Foster; Keynote - Utilization of dense gas technologies for the fabrication and
formulation of nano-biomaterials
1435 268. Matt Yates; Microencapsulation through hybrid aqueous/supercritical carbon
dioxide processing of polymer colloids
1500 269. Ana Rita C. Duarte; Exploring supercritical fluid technology for the development
of controlled drug delivery
1515 Break
1535 270. Katsuto Otake; Liposome formation with supercritical CO2 as an alternative
solvent
1600 271. Gerhard Muhrer; Solid dispersions by compressed fluid antisolvent precipitation
31
Technical Program
1630 272. Geert Verreck, The use of compressed carbon dioxide to broaden the applicability
of hot stage extrusion for drug delivery
1700 273. Paolo Caliceti, Fabrication of lipid nanoparticles for low molecular weight and
biotech drug delivery by gas compressed techniques
1730 End of Session
32
Oral Abstracts
Abstracts of Oral Program
Plenary 1
1
TARGETTED BIORESPONSIVE NANOLIPID PARTICLES
Francis C. Szoka, Departments of Biopharmaceutical Sciences and
Pharmaceutical Chemistry, University of California, San Francisco
94143-0446, USA; szoka@cgl.ucsf.edu
There is a growing expectation that targeted drug delivery will greatly improve anticancer
therapy. This expectation is fueled by the increasing number of FDA approved passively
targeted and actively targeted carriers of therapeutic agents. Doxil™, a sterically stabilized
liposome that encapsulates doxorubicin, is an early example of a passively targeted
nanosystem. Sequus, Inc. the company co-founded in 1981 by Demetri Papahadjopoulos
and I developed Doxil™ a sterically stabilized liposome containing doxorubicin. But is
there “room at the bottom” for more complex novel bioresponsive nanosystems?
In this talk I will discuss various approaches our group have pursued to create and study pH
and redox-responsive liposomes (nanolipoparticles), peptides and polymers. The possible
advantages and barriers to the commercialization of systems studied by us will be
discussed. As an example I’ll use polyamidoamine dendrimers, gene transfer reagents in
1993 and how the development of biodegradable dendrimers by the Frechet group now
position them as outstanding candidates to make contributions in others aspects of
medicine, from drug design and delivery to imaging and tissue repair. I will describe the
special features of dendrimers, not enjoyed by liposomes---small diameter and
monodispersity-and how dendrimer architecture and size influences their pharmacokinetic
properties. Pharmacokinetics, bioresponsive drug release and biodegradation will be
increasingly important as nanosized drug carriers approach clinical trials.
A1 – Invited Paper
CARRIER FOR NANOPARTICLES - TARGETED DELIVERY OF
WATER-INSOLUBLE DRUGS
Hans Bäumler, Steffen Bauer, Myriam Brähler, Andreas Lemke, Jan
Möschwitzer, Verena Staedtke, Charité - Universitätsmedizin Berlin, D-10098
Berlin, Germany, hans.baeumler@charite.de
2
Highly efficient drugs for the therapy of cancer or cerebral fungal infections are very often
water insoluble. The design of nanoparticles of these drugs is very useful, but it is
necessary to solve the problem of targeting as well as of drug availability at the target cells.
We developed a method for loading erythrocytes with nanoparticles utilizing them as a
potent carrier system characterized by excellent biocompatibility, biodegradability and
non-immunogenic properties. As very poorly water soluble drug served Amphotericin B.
The loading procedure leads to a final concentration of 4pg AmB per erythrocyte. It was
proven that an amount of only 750 AmB-loaded erythrocytes per ml is sufficient to reach
an antifungal effect, representing one millionth of the physiological erythrocyte
33
Oral Abstracts
concentration in human blood (4-6*109 per ml). Additionally loading the erythrocytes with
magnetite nanoparticles and magnetically focussing them to the desired sites can realize
targeting of organs or tissues. Loading erythrocytes simultaneously with both, AmB and
magnetite, did neither reduce the AmB concentration per erythrocyte nor its bioactivity.
Additionally, magnetite loaded erythrocytes can be visualized by MRI, offering the
opportunity for diagnostic monitoring of the therapy. To achieve effectiveness in CNS
fungal infections, we incorporated AmB loaded erythrocytes into RES cells. Due to
damage of the blood brain barrier (BBB) in infections RES cells cross the BBB in a higher
percentage than usual. In-vitro phagocytosis assays using AmB loaded erythrocytes show a
significant inhibition of free fungal activity. This effect can be observed in viability assays
using flowcytometric analysis and direct cell culture assay. The advantages of our
erythrocyte-carrier-system are not limited to AmB. Any other water insoluble drug has
potential to be loaded onto erythrocytes thereby exploiting the advantages of our carrier
system. Due to their unique qualities erythrocytes can be used as therapeutically drug
delivery systems, which cannot just deliver a high dosage of different drugs but also
protects them from inactivating effects and minimizes side reactions. The additional
diagnostic capacities as MRI contrast media and the possibility to focus on certain tissues
make our delivery system one of the most versatile drug carriers.
A1 – Invited Paper
DEVELOPING TUMOR TARGETED CONTROLLED RELEASE DRUG
VECTORS ON COLLOIDAL GOLD NANOPARTICLE
Giulio F. Paciotti1, David Kingston2, Lonnie Myer1, and Lawrence Tamarkin1
1
CytImmune Sciences, Inc. Rockville MD, 20850 and 2Department of
Chemistry Virginia Polytechnic Institute and State University, Blacksburg,
VA, 24061; gpaciotti@cytimmune.com
Colloidal gold nanoparticles are being used as a new drug delivery vector to deliver
multifaceted drug therapies to solid tumors. We have developed two unique colloidal gold
nanoparticle vectors designed to deliver both biologic and chemotherapeutic-based
therapies to solid tumors. The first of these vectors, termed CYT-6091, is designed to
target the delivery of tumor necrosis factor alpha (TNF) to solid tumors. Briefly
CYT-6091 is comprised of a 26 nm colloidal gold nanoparticle that is covalently bound
with TNF and a 20 kD form of thiolated PEG (PEG-THIOL). Each component in this
multivalent vector performs a function: First the presence of the PEG-THIOL moiety
prevents uptake and clearance of the vector by the reticuloendothelial system. Second the
colloidal gold nanoparticle not only serves as the platform for assembling the nanoparticle
vector but due to its size provides initial access to the tumor milieu by passive
extravasation of the leaky tumor vasculature. Third, the particle bound TNF not only
serves as the therapeutic but also acts as a tumor targeting ligand. By targeting the delivery
of TNF to solid tumors, CYT-6091 improves both the safety and efficacy of TNF
treatment. Nevertheless given the heterogeneity of tumor cells present in a given solid
tumor and the heterogeneity of solid tumors themselves, it is unlikely that single agent
therapies will, regardless of their ability to target the tumor, show efficacy over a broad
spectrum of cancers. To address this potential limitation we have developed a
second-generation vector, termed CYT-21001, that uses the tumor targeting and
3
34
Oral Abstracts
therapeutic properties of TNF to target the delivery of a chemotherapeutic prodrug. In
addition to the TNF and PEG-THIOL moieties, CYT-21001 contains a prodrug form
paclitaxel, which can be triggered to form native paclitaxel at the tumor site to induce
potent anti-tumor responses in solid tumors which are refractory to TNF. Thus, colloidal
gold nanoparticles are the core of a new family of nanomedicines for the treatment of
cancer.
A1 – Contributed Paper
PRPEARATION AND CHARACTERIZATION OF
ELECTROSTATICALLY STABILIZED DISPERSIONS OF GOLD
NANOPARTICLES FOR MEDICAL AND BIOLOGICAL APPLICATIONS
Dan V. Goia and Daniel Andreescu, Center for Advanced Materials
Processing, Clarkson University, Potsdam, NY 13699-5814, USA,
goiadanv@clarkson.edu
4
The paper describes a convenient, rapid, and reproducible precipitation method to
synthesize stable dispersions of uniform gold nanoparticles by reducing aqueous solutions
of tetrachloroauric acid with iso-ascorbic acid at ambient temperature. The influence of the
experimental conditions on the size of the gold particles and the stability of the final sols,
investigated by dynamic light scattering and UV-VIZ spectrophotometry, will be discussed
in detail. It was determined that the size of the resulting nanoparticles is affected by the
concentration and the pH of gold solution, while the stability of the electrostatically
stabilized final sols is strongly dependent on the excess of either reactant in the system, the
ionic strength, and the temperature of the precipitation. Since the preparation process does
not require the addition of dispersing agents to ensure the stability of the sols, the resulting
gold nanoparticles have a clean surface and are, therefore, suitable for a wide range of
surface modifications for applications in medicine and biology. It was also found that the
addition of only trace amounts of organic molecules or inorganic ions to the sols triggers
drastic changes in the position and the shape of the surface plasmon band of the gold
particles, suggesting possible uses of these dispersions for sensing applications.
A1 – Contributed Paper
LOW MOLECULAR WEIGHT HYDROGELATORS AS ORAL DRUG
DELIVERY SYSTEMS
Arianna Friggeri, Kjeld J.C. van Bommel, Menno R. de Jong, Gieta van der
Schaaf, Erna Bulten, Marijke Haas, Eduard Post, Anita Meter-Arkema,
Biomade Technology Foundation, Nijenborgh 4, 9747 AG Groningen, The
Netherlands; friggeri@biomade.nl
5
Low molecular weight gelators (LMWGs) are small organic molecules capable of
self-assembling into extended three-dimensional networks by means of hydrogen bonding
and other supramolecular interactions. Such networks very often consist of nano-sized
fibers, with a well-defined molecular architecture, in which solvent molecules become
trapped, leading to the formation of gels. LMWGs possess small and relatively simple
35
Oral Abstracts
structures. This means that they can be easily and uniformly functionalized. Furthermore,
LMWG gels can show very rapid response times to stimuli such as temperature, pH, light,
chemicals, or combinations of these. Biomade Technology has developed several classes
of low molecular weight gelators that can be used for applications in pharmaceuticals
formulation, as well as in cosmetics and personal care. These gelators can be used to
thicken or gelate a wide variety of solutions, solvent mixtures, and emulsions. Oral
administration is the most convenient way to treat patients, but preparing a suitable
formulation for oral delivery is often hampered by the poor aqueous solubility of many
active substances obtained via modern combinatorial synthesis procedures. Most of the
approaches that have been used to overcome insolubility result in clinical problems such as
poor and erratic bioavailability. BiOMaDe Technology has discovered that precipitation of
poorly water-soluble drugs in the presence of the fibrous network formed by the gelator
results in very finely dispersed drug particles that dissolve rapidly in the gastrointestinal
tract. In vitro dissolution studies and in vivo bio-availability studies using lipophilic drugs,
such as furosemide and itraconazole, formulated with low molecular weight hydrogelators
for oral drug delivery will be presented.
A1 – Invited Paper
CELL GROWTH AND CELL MANIPULATION BASED ON 2 AND 3
DIMENSIONAL ORGANIZATION OF NANOSIZED MATERIALS OF
DIFFERENT MORPHOLOGY
Michael Giersig, CAESAR Research Center, Ludwig-Erhard-Allee 2, 53175
Bonn, Germany; giersig@caesar.de
7
The fabrication of one-dimensional (1-D) inorganic nanomaterials (including nano-wires,
tubes and nanoparticles) with a well-ordered structure has recently become of utmost
importance for biomedical applications. A method based on conventional lithography for
selective layer-by-layer material deposition is employed to fabricate stable networks
having controlled geometry, topography, and composition. This procedure offers
unconventional micro- and nanofabrication routes to yield complex, free-standing
matrices, resulting in array designs with extremely high reproducibility. The array design
consists of periodic compartments made up of intercrossed nanomaterials of different
morphology. The creation of 2-D and 3-D scaffolds with regard to the size and morphology
of growing cells will be discussed. In the second part, we will present the possibility of cell
manipulation using nanomaterials. Our method allows us to deposit organic and inorganic
nanomaterials in bacteria, cancer and yeast cells. The principles of this method and some
examples of cell modification will also be presented.
36
Oral Abstracts
A1 – Invited Paper
POROUS MICROPARTICLE TECHNOLOGY FOR IMAGING AND
DRUG DELIVERY
Julie Straub, Don Chickering, Howard Bernstein, Acusphere, Inc., 500
Arsenal Street, Watertown MA 02472, USA; julie.straub@acusphere.com
8
Porous particles in the submicron to micron size range have been produced using a
patented porous microparticle technology. The technology uses a modified spray drying
process that has been validated for aseptic operation. Particle size, porosity and
morphology were engineered during the spray drying process using pore forming agents,
such as volatile salts. These agents were added to the material to be spray dried and were
removed during the drying process. The modified spray drying process was performed
using a patented multi-chamber spray dryer. Three product candidates based on the porous
microparticle technology have been studied in the clinic. The porous microparticle
technology was first applied to the production of AI-700, an intravenously administered
ultrasound contrast agent for detection of coronary artery disease. AI-700 consists of
internally porous particles, about two microns in diameter, which contain perfluorobutane.
The shell material is poly (lactide-co-glycolide). AI-700 is in Phase III clinical trials. The
second product candidate studied in the clinic is AI-850, which is a readily dissolving
porous microparticle formulation of paclitaxel for intravenous administration. AI-850 has
been studied in a Phase I dose escalation clinical trial.The third product candidate studied
in the clinic is AI-128, which is a sustained-release, dry powder formulation of a widely
used asthma drug that is often administered multiple times daily. AI-128 consists of
honeycomb-like microparticles of the asthma drug encapsulated in a slowing dissolving
shell material. A Phase I clinical trial with AI-128 has been completed and demonstrated
that the asthma drug was released from the microparticles in the lung over a 12 to 24-hour
period. In summary, the spray drying process yields particles with average sizes in either
the nanoparticle or microparticle size range which are appropriate for pulmonary, oral, and
subcutanous administration.
A1 – Contributed Paper
DEVELOPMENT OF MAGNETIC NANOCARRIER CONSISTING OF
GOLD AND IRON OXIDE FOR BIOMEDICAL APPLICATIONS
Satoshi Seino, Takuya Kinoshita, Takashi Nakagawa, Takao A. Yamamoto,
Grad. Sch. of Eng., Osaka Univ., 2-1, Yamadaoka, Suita, Osaka, Japan.;
Takefumi Doi, Shinsaku Nakagawa, Grad. Sch. of Pharm. Sci., Osaka Univ.,
1-6, Yamadaoka, Suita, Osaka, Japan.; Masakazu Furuta, Grad. Sch. of Sci.,
Osaka Pref. Univ., 1-2, Gakuencho, Sakai, Osaka, Japan.; and Noriyuki
Ohnishi, Magnabeat Inc, 5-1, Goikaigan, Ichihara, Chiba, Japan.;
seino@mit.eng.osaka-u.ac.jp
9
We are developing a new technique for the preparation composite nanoparticles consisting
of magnetic iron oxide and gold in an aqueous solution system using radiochemical or
sonochemical process. Iron oxide nanoparticles were dispersed in an aqueous solution
37
Oral Abstracts
containing Au ions together with some alcohols and polymers. The solution was irradiated
with gamma-ray, electron beam or ultrasonic wave to reduce Au ions. After the irradiation,
small Au nanoparticles were immobilized on the surface of iron oxide nanoparticles. Some
composite nanoparticles synthesized under appropriate conditions showed good
dispersibility in an aqueous solution, and substantially no sedimentation occurs even after
50 days. The composite nanoparticle carries functions of the gold particle and
maneuverability by a magnetic field. As the gold part firmly combines with molecules
possessing mercapto groups, the composite nanoparticles can be easily modified with
appropriate molecules for each purpose. We have already confirmed that the Au part in the
composite nanoparticles can be combined with sulfur containing molecules such as amino
acids (cystine and methionine), and thiol-modified oligonucleotide. We have demonstrated
that a target oligonucleotide was easily and specifically picked up from an aqueous
solution containing target and nontarget oligonucleotides by magnetically attracting these
nanoparticles to which a probe oligonucleotide immobilized. The amount of separated
target oligonucleotide depended on the size of Au grains in the composite nanoparticles.
We found that 0.75 nmol oligonucleotide was picked up by 1-mg particles, and about 10
minute was enough for the hybridization process. The present results indicate that the
composite nanoparticle is expected as a new magnetic nanocarrier for various
biotechnological applications.
B1 – Keynote Paper
OPTIMIZING DRUG DELIVERY – EFFICIENT FORMULATION
DEVELOPMENT AND SCALEABLE MANUFACTURING
METHODOLOGY
Irwin Gruverman, P.E., MFIC Corp.(Microfluidics Div.), 30 Ossipee Rd,
Newton, MA 02464, USA; vcirv@alum.mit.edu
10
Formulation science enables delivery and performance of active pharmaceutical
ingredients (API’s). In medicine, coatings, foods and other disciplines requiring normally
unstable mixtures (dispersions, emulsions) formulation optimization is necessary. The
quality of emulsions and dispersions is key to successful formulation, microemulsions,
uniform nanosize structures are most stable, if few outlier sized structures exist to serve as
nucleation sites for phase condensation. Surfactants and other additives are often needed.
Minimum additive formulations are usually desired and enabled by appropriate high
energy processing. Drug delivery by any modality requires control of particle or droplet
size, to control penetration, retention and pharmacokinetics. Two major factors govern
performance – formulation and process equipment to control energy input. Development is
most efficient if composition and process trials are interactively developed. Thus, there is a
need to perform many sequential and parallel studies as composition and process
conditions are altered. Microfluidizer® Processors have enabled optimal formulation
development for more than 20 years. The lab version is designed to clean rapidly and can
perform dozens of trials in a day. Results obtained at 10 – 100 ml/min will scale linearly to
60 liters/min in production processors. Unique fixed geometry, constant shear conditions,
and reproducible process pressure (up to 40000 psi) maximize and control energy
deposition. Shear levels are an order of magnitude greater than in other process equipment,
38
Oral Abstracts
such as conventional homogenizers and rotor/stator mixers. Fixed geometry operation
assures minimal deviation in product characteristics. This talk will highlight 20 years of
evolution of Microfluidizer processor systems to current equipment. It will address many
application examples in biopharmaceutical formulation development and manufacturing,
in pharmaceutical processing, and in protein harvesting from cell suspensions. Practical
feedback from the more than 3000 processors in the field, as well as data developed in
Microfluidics’ three applications laboratories (Boston, Los Angeles and Frankfurt,
Germany) will be presented. Based on this considerable formulation applications database,
we modestly conclude that modern formulation science is optimized by using
Microfluidizer Processor technology and experience. Finally, a brief view of new
technology based on Microfluidizer Processors, will be given. This is a new approach to
continuous chemical reaction systems, which could revolutionize the manufacture of
chemicals, including many API’s. It also allows easy solubilization by controlled
recrystallization of insoluble refractory API’s which are potent drugs but which have
resisted useful formulation development.
B1 – Invited Paper
LIPID INJECTABLE EMULSIONS: PHARMACOPEIAL AND SAFETY
ISSUES
David F. Driscoll, Harvard Medical School, Baker Building Suite 605, 185
Pilgrim Road, Boston, MA, USA; ddriscol@bidmc.harvard.edu
11
Lipid injectable emulsions intended for nutrition support of patients incapable of
assimilating nutrients via the gastrointestinal tract have been administered for over 40
years. Despite this record of clinical use, there are no official pharmacopeial standards
worldwide regarding its stability and subsequent safety in humans. Moreover, drugs have
also been added to these emulsions such as the anesthetic agent, propofol. With a average
droplet size of approximately 300 nm, these formulations are considered
“mini-emulsions”, require energy to be formed and are thermodynamically unstable.
Consequently, they have short shelf lives. Instability manifests as a growing population of
large-diameter fat globules as a result of coalescence. As this population gets larger, the
risk of embolic phenomena increases upon intravenous infusion. Embolism of the
pulmonary, hepatic or cerebral microvasculature can prove to be fatal, especially in the
face of critical illness. Recently, the United States Pharmacopeia has proposed Chapter
<729> entitled “Globule Size Limits in Lipid Injectable Emulsions”. The not-to-exceed
limits proposed universally apply to 10, 20 and 30%w/v oil-in-water nutritional emulsions,
and include an intensity-weighted mean droplet diameter of < 500 nm, and a
large-diameter fat globule limit expressed as a volume-weighted percentage of fat > 5-um
or PFAT5 of < 0.05%. The rationale for these limits and associated methods of analysis, as
well as bench and animal research in support of Chapter <729>, will be described.
39
Oral Abstracts
B1 – Contributed Paper
DROPLET SIZE DISTRIBUTION OF LIQUID-LIQUID SYSTEMS FROM
UV-VIS SPECTRA
Maria-Teresa Celis*, Luis H. Garcia-Rubio**, *Laboratory FIRP and
Laboratory of Polymers and Colloids (POLYCOL) -Chemical Engineering
Department, University of the Andes- Mérida Venezuela; **Chemical
Engineering Department – University of South Florida- Tampa , FL, USA;
celismt@ula.ve
12
The stirring of a surfactant/water/oil system result in the generation of droplet populations
determined primarily by the nature and amount of emulsifier, mixing characteristics and
emulsion preparation. The estimation of the droplet size and droplet size distribution is
important data, not only because they are linked with the manufacturer process, but also
they give valuable information on the properties of the dispersed phase. This research
demonstrates the potential of spectroscopy as a tool for characterization of liquid –liquid
systems in terms of droplet size distribution as a function of the oil concentration and of
physicochemical variables. The opportunity of obtaining information from a single
multiwalength measured makes UV-Vis spectroscopy a powerful tool for characterization
of dispersed systems.
B1 – Invited Paper
APPLICATIONS OF VITAMIN E BASED FORMULATIONS
Lynn Gold, and Alex Tustian, Sonus Pharmaceuticals Inc, 22026 20th Avenue
SE, Bothell, WA 98021, USA; lynng@sonuspharma.com
13
Vitamin E has been shown to facillate solubilization of various lipophilic drugs. Various
parmeters have been optimized to produce drug emulsions which are suitable for
evaluation as injectable drug products. In each case, nanodroplet (60-80 nanometer )
formulations have been achieved with 10 mg/mL drug loading. The goal of the
nanodroplet is to localize in the tumor taking advantage of the leaky vasculature. These
formulations are suitable for a variety of lipophilic drugs including taxanes and
camptothecins. In the case of taxanes, the tolerability of an unmodified taxane has been
improved, the drug loading has been increased, the volume injected has been reduced and
the infusion time has been reduced with a vitamin E emulsion versus the marketed
cremophor formulation. The final drug formulation is manufacturable under GMP
specifications at a commercially viable scale. Early data on the campothecin emulsion
shows similar benefits.
B1 – Invited Paper
GENERATION OF MONODISPERSE DOUBLE EMULSIONS IN A
PLANAR MICROFLUIDIC NETWORK
Takasi Nisisako, Toru Torii, Department of Precision Engineering, Graduate
School of Engineering, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku,
14
40
Oral Abstracts
Tokyo, Japan; nisisako@intellect.pe.u-tokyo.ac.jp
Double emulsions have attracted considerable attention because of their potential
applications in foods, cosmetics, and pharmaceutics. Conventionally, two-stage vigorous
mixing is employed in practical formulation of double emulsions, but resultant products
have broad size distribution. Here, we present a planar microfluidic platform having
hydrophobic and hydrophilic components for preparing monodisperse double emulsions.
Monodisperse double emulsions can be formed by a two-step method of droplet breakup in
a series of T-junctions. For a water-in-oil-in-water (W/O/W) emulsion, for example,
to-be-enclosed aqueous drops of uniform sizes are periodically formed upstream at the
hydrophobic T-junction; then, in a continuing series, monodisperse organic droplets, that
encase the aqueous droplets, are formed downstream at the hydrophilic T-junction.
Microchannels were fabricated on glass plates by conventional lithographic techniques.
For aqueous droplet formation, channel surface was partially modified to be hydrophobic
by using a water-soluble siliconizing agent. Surfactants were added to intermediating and
external phases to stabilize the prepared multiple-phase dispersions. In the production of
W/O/W emulsions, for example, each of the monodisperse aqueous drops (diameter = 52
μm, CV = 2.7%) could be encapsulated in an organic droplet (diameter = 83 μm,
CV=2.8%). The size of the droplets and the number of internal droplets could be varied by
changing the flow conditions. Both W/O/W and oil-in-water-oil (O/W/O) emulsions were
prepared by reversing the order of hydrophobic and hydrophilic components. Also, double
emulsions, including internal droplets of two different compositions were prepared using a
cross-junction as the upstream component. Monodisperse polymeric microcapsules could
also be engineered by curing intermediating organic phase in W/O/W droplets. We believe
that the method we developed has many applications in various fields, such as, analysis of
confined chemical reactions, biological screening, drug delivery systems and materials
science, etc.
B1 – Invited Paper
APPLYING NANOCOMPOSITE COATINGS ON MEDICAL
DEVICES USING ELECTRONANOSPRAY
Robert A. Hoerr, Nanocopoeia, Inc., 1246 W. University Ave., St. Paul, MN
55104, USA; bob.hoerr@nanocopoeia.com.
15
The drug-eluting coronary stent—first introduced in the United States in 2003—has
transformed interventional cardiology by producing significantly improved clinical
outcomes compared with earlier techniques that used balloon angioplasty or bare metal
stents to restore blood flow through blocked coronary arteries. The market for drug-eluting
stents is expected to exceed $6 billion in 2006, making this perhaps the fastest market
introduction in medical device history. Despite this success, the current products represent
only the first wave of development, and there is much opportunity remaining for both
process and therapeutic advances. Nanocopoeia uses its novel, proprietary
ElectroNanospray™ process to apply nanocomposite coatings onto coronary stents and
other implantable medical devices. The ElectroNanospray™ process has several unique
features and benefits. The cone-jet mode of spray operation produces highly charged,
41
Oral Abstracts
uniform, monodisperse nanoparticles comprised of one or more components. Coating of
the target is non-line-of-sight and directed by the established electrical field, which aids in
the uniform coating of pieces with intricate architecture. The proprietary spray head
enables the application of multiple agents in a nanocomposite matrix. The process
accommodates a range of polymers, solvents, and drugs typical of those that are
appropriate for coating stents and other implantable devices. Using these materials,
coatings are applied as nanoparticles comprised of drug or drug and polymer in a solvent
carrier. The resulting finishes of these coatings range from a highly preserved
nanoparticulate architecture to a smooth surface. Characterization of these coatings by a
variety of techniques, including cryomicrotomy, SEM and FTIR microscopy, demonstrates
a highly uniform composite matrix that is stable as the stent is balloon-expanded.
B1 – Contributed Paper
SILICONE BASED CONTROLLED RELEASE DRESSING FOR
ACCELERATED PROTEOLYTIC DEBRIDEMENT
Kurt F. Bradstadt, 1 James W. Crissman, 1 Paal C. Klykken, 1 Csilla Kollar, 1
Thomas H. Lane, 1 Xavier Thomas, 1 Gregory S. Whitaker, 1 Richard Bott, 2
Grant Ganshaw, 2 Mark Gebert, 2 Isabelle Mazeaud, 2 Mae Saldajeno, 2 Lillian
B. Nanney, 3 Jeffrey M. Davidson, 3,4 Dow Corning Corporation,1 Midland, MI;
Genencor International,2 Palo Alto, CA; Vanderbilt School of Medicine 3 and
VA TVHS Medical Center, 4 Nashville, TN; csilla.kollar@dowcorning.com
16
Unique solutions for rapid enzymatic debridement were developed by the combination of
silicone materials that have demonstrated utility in wound care applications with the
performance of a genetically engineered, broad spectrum protease. Silicone emulsion
technology enables hydrophilic enzymes to be stabilized with hydrophobic silicone
materials. The enzyme is a serine protease of the subtilisin family, which has not been
tested previously as a debriding agent. The dried emulsion incorporates a protease in a
dehydrated state that shows excellent performance in accelerated stability tests, with
retention of ~90% of the initial activity for an equivalent of 18 months’ storage at room
temperature. The combination was tested in a porcine burn model. The silicone delivery
device acted synergistically with the enzyme to promote rapid debridement in the moist
wound environment. Tissue fluids from the wound triggered reproducible and complete
release of enzyme from the emulsion within eight hours. There was essentially complete
removal of hardened eschar from full thickness burns after a single 24-hour treatment.
Rapid debridement by the test material resulted in considerable exudate, which was easily
managed with an absorbent dressing layer. There was a clear dose-response with various
enzyme concentrations. Compared to controls and the benchmark material, debridement
and progression to the healing phase were faster, and tissues unaffected by thermal injury
appeared to remain normal. This technology, with the core silicone attributes of oxygen
permeability, moisture retention, and friendly skin adherence properties, can serve as the
basis for a number of drug delivery and wound care applications.
42
Oral Abstracts
C1 – Invited Paper
SUPERCOOLED SMECTIC NANOPARTICLES - DEVELOPMENT AND
CHARACTERIZATION OF A NOVEL DRUG DELIVERY SYSTEM
Heike Bunjes, Judith Kuntsche, Markus Drechsler, Friedrich Schiller
University Jena, Institute of Pharmacy, Department of Pharmaceutical
Technology, Lessingstr. 8, 07743 Jena, Germany, and Michel H.J. Koch,
EMBL, Hamburg Outstation c/o DESY, Notkestr. 8, 22603 Hamburg,
Germany; Heike.Bunjes@uni-jena.de
17
As an approach to improve the drug incorporation capacity of lipid nanoparticles with a
nonliquid core, nanoparticles in the thermotropic liquid crystalline smectic state have been
developed. These nanoparticles are based on cholesterol esters like, e.g., cholesteryl
myristate. In the bulk, the materials of interest are crystalline at room temperature. When
dispersed into the colloidal state, e.g., by melt-homogenization with physiologically
acceptable emulsifiers the smectic state can, however, be retained for pharmaceutically
relevant periods of time at room and body temperature in optimized systems. Using
cholesteryl myristate as model matrix material, the stability against recrystallization of
nanoparticles prepared with different surfactants was investigated. As a general trend,
nanoparticles stabilized with surfactants containing fatty acid chains (e.g., phospholipids,
fatty acids, sucrose ester) seem to be less stable against recrystallization than nanoparticles
stabilized with typical polymeric surfactants (e.g., poloxamers, polyvinyl alcohol). This
may result from different crystallization behaviors observed upon cooling in DSC
experiments: In contrast to stabilization with polymeric surfactants, emulsifiers with fatty
acid chains lead to multiple crystallization events. Phospholipid-containing dispersions
display a usually bimodal crystallization event the course of which depends on the particle
size distribution and seems to be correlated with ultrastructural parameters of the
dispersion (ocurrence of cholesteryl myristate nanoparticles with different shapes). For
these dispersions, a strong particle size dependence of the recrystallization tendency upon
storage was observed. The stablity of the smectic state against recrystallization is improved
when esters with a lower crystallization tendency like cholesteryl oleate or cholesteryl
nonanoate are admixed to the cholesteryl myristate matrix. Cholesteryl nonanoate can also
be used as the only matrix component to prepare stable smectic nanoparticles. First drug
loading investigations on cholesteryl myristate nanoparticles revealed that the dispersions
can stably incorporate model substances without negative influence on the matrix state and
colloidal stability of the nanoparticles.
C1 – Invited Paper
SUSTAINED AND ACTIVE PROTEIN DELIVERY FROM
PHOTO-CROSS-LINKED BIODEGRADABLE ELASTOMER
MILLI-CYLINDERS
Brian Amsden, Department of Chemical Engineering, Queen’s University,
Kingston, Ontario, Canada K7L 3N6; amsden@queens.ca
18
Although the potential and advantages of implantable devices for localized, prolonged
43
Oral Abstracts
protein therapeutic delivery have long been recognized, there are currently very few
formulations for this purpose currently in the clinic. This is a result of the difficulty in
maintaining the activity of the protein within the delivery device prior to release. In an
attempt to overcome this problem, we have investigated the potential of osmotic pressure
induced rupturing of polymer systems for protein release. In these devices, the protein is
distributed as solid particles within a rubbery polymer matrix. As it is desirable to have a
biodegradable implant, a biodegradable elastomer was utilized that was cross-linked via
irradiation with UV light. The cross-linking thus occurs at ambient temperature and does
not denature the protein. To facilitate implantation, the device were prepared in
milli-cylindrical form. The in vitro release kinetics of three therapeutically relevant
proteins, interferon-gamma, interleukin-2, and vascular endothelial growth factor were
measured and demonstrated to be constant and similar. Moreover, the bioactivity of the
released proteins remained high during the release period. The release rate and duration
was readily manipulated by varying formulation parameters such as the mechanical
properties of the rubbery polymer used, and the amount and nature of excipients
co-lyophilized with the proteins.
C1 – Invited Paper
PHARMACEUTICAL APPLICATION OF CATANIONIC COMPLEXES –
SUSTAINED DRUG RELEASE FROM GELS
Katarina Edsman, Uppsala University, Dept. of Pharmacy, Uppsala,
Sweden; katarina.edsman@farmaci.uu.se
19
Gel formulations have many applications in different routes of administration, for example
for ocular, cutaneous, nasal and oral use. Where an aqueous solution gives a short contact
time to the mucosa a gel can prolong this period of time because of its rheological and
mucoadhesive properties, making an enhanced absorption of the drug substance possible.
However, a gel usually contains more than 90 % water, allowing the drug molecule to
move almost as freely as through pure water. To fully benefit from the prolonged contact
times the release of the drug must be sustained. One possibility of sustaining the release is
to make the drug interact with or be part of a slower diffusing species. Recently the
possibility of using catanionic aggregates with an active drug molecule was investigated
for prolonging the release of the drug. Catanionic aggregates are formed spontaneously in
aqueous mixtures of a large selection of cationic and anionic surfactants. At low
concentrations of the catanionic components vesicles and micelles are formed,
accompanied by two-phase regions and precipitates. The micelles formed in a catanionic
mixture range from simple spherical ones, via rod-like micelles, to branched micellar
aggregates. The properties of traditional catanionic mixtures are relatively well known.
Lately we have shown that not only traditional surfactants form these mixtures, but also
structurally more complex surface active drug compounds. We have investigated at what
extent mixtures of drug substances and oppositely charged surfactants form catanionic
aggregates and studied the release from gels using vesicle and micelle phases. The results
show that catanionic aggregates seem to form frequently in these kinds of mixtures. The
drug release studies show that catanionic drug surfactant mixtures is beneficial for
obtaining prolonged release from gels, as the drug release using catanionic vesicles and
44
Oral Abstracts
micelles was prolonged between 10 and 100 times compared to the release of pure drug
substance from the gel. The mechanism suggested for this prolonged release is that the
vesicles or micelles are larger than the pores of the gel, rendering them unable to move
through the gel as large aggregates, whereas free molecules or smaller aggregates will
diffuse through the gel.
C1 – Invited Paper
MODIFIED POLYACRYLIC AND POLYSACCHARIDE
NANOPARTICLES FOR CONTROLLED EXTRACTION AND RELEASE
P. Somasundaran and Somil Mehta, NSF Industry/University Cooperative
Center in Novel Surfactants, Columbia University, New York, NY10025,
USA; ps24@columbia.edu
20
Polymeric nanoparticles are reservoirs which can encapsulate active substances in order to
isolate them from the surrounding environment and then to release them as required.
Nanoparticles can be used for preparation of formulations containing drugs, vitamins,
steroids, proteins, enzymes, flavors and fragrances. Such nanohybrids are mainly based on
crosslinked polymers. High pressure liquid chromatography (HPLC) and ultraviolet
spectroscopy studies showed that the polymeric nanoparticles after modification with
charged and hydrophobic groups show higher extraction of attributes such as drugs and
fragrances. The release was observed to be pH dependent and thus offered a means of
controlling the release of active substances in body. The potential of these nanoparticles for
extraction of various active substances were investigated using Surface Plasmon
Resonance (SPR) technique. The technique here is based on electromagnetic waves
decaying evanescently at a substrate/solution interface. The evanescent behavior of the
waves make this technique surface specific and sensitive to long and short changes in
refractive index of the layer next to the substrate and hence to adsorption/desorption
(extraction/release) of molecules in the surface layer. The release rates of drug and
fragrance were thus established based on changes in the refractive index of tightly bound
layers of nanohybrids. It was observed that the release can be controlled by varying
properties such as cross linking density, temperature sensitivity and swelling/ shrinking
capacity. The shape and size of the nanohybrids offer a good opportunity to produce a
family of nanocarriers in the personal care industry.
C1 – Contributed Paper
ENZYMATIC REACTIONS IN MICROCAPSULES
Dieter Trau1, Wing Cheung Mak2, Cheung Kwan Yee2, 1, 2 Division of
Bioengineering and 1Department of Chemical & Biomolecular Engineering,
National University of Singapore (NUS), Singapore; bietrau@nus.edu.sg
21
Here we report on the use of the Layer-by-Layer (LbL) technology to create microcapsules
filled with different enzymes or mixture of enzymes and substrates and their use as a
microreaction compartment to perform biochemical reactions. With our technology of
“Matrix Assisted LbL-Encapsulation” we are able to encapsulate virtually any enzyme,
45
Oral Abstracts
mixtures of enzymes or complex mixtures of enzymes and substrates into LbL-capsules.
Capsule permeability is controllable by the number of LbL-layers to control diffusion of
substrates into the capsule and entrapment of polymeric products of enzymatic reactions.
Encapsulation efficiency for proteins, enzymes and oligonucleotides was studied. Capsules
with ~10 LbL-Layers (PAH/PSS) are extraordinary heat stable and successful PCR
reactions within microcapsules could be achieved. The use of microcapsules as reaction
compartment has several advantages: Large number of individual reactions in parallel;
small reaction volumes; small reagent/substrate consumption; high throughput. Our novel
encapsulation technology, encapsulation efficiency, stability, PCR reactions in
microcapsules and various applications will be presented.
C1 – Contributed Paper
BIO GOES NANO OR NANO GOES BIO
Sabine Fischer, Lawrence Batenburg, Renz van Ee, Jacco Eversdijk, Klaas
Timmer, TNO Science and Industry, Innovative Materials, Eindhoven, The
Netherlands; sabine.fischer@tno.nl
22
TNO as an institute for applied science is working for more than 10 years in the field of
nanotechnology, especially in the preparation of hybrid nano-composites. Our group has
developed a new technology – the so-called Planomers® Technology - that enables the
incorporation of inorganic nanoparticles into the most existing polymer matrices on a real
nano-scale. By applying this technology to commodity and engineering plastic an
enormous improvement of properties like mechanics, barrier or flame retardancy can be
achieved. During the last years our research activities became more and more focused on
the application of these nanotechnological principles to natural polymers (biopolymers),
like polysaccharides and proteins to develop new biodegradable packaging materials and
controlled release systems for agriculture and building industry. On the other hand, our
knowledge on nano-composites in general has lead to new applications in the field of food,
pharmacy and biomedical materials. The TNO Planomers® Technology is not only
improving the properties of plastics but can also lead to healthier food by incorporating
inorganic (nano)minerals, to improved drugs by using nanocomposite materials as drug
carriers or to the 3D-processing (Rapid manufacturing) of nanocomposite materials for
biodegradable and biocompatible scaffolds for tissue engineering. The research results of
the nanotechnology for hybrid biological system and its practical application in food,
pharmacy and medical industries will be presented and discussed in detail.
46
Oral Abstracts
C1 – Invited Paper
DEVELOPMENT OF FORMULATIONS AND EQUIPMENT FOR THE
SPRAY DRYING OF HIGH VALUE ACTIVE INGREDIENTS FOR THE
PHARMACEUTICAL INDUSTRY
Irwin C. Jacobs, Robert E. Sparks, John Cooper; Particle and Coating
Technologies, Inc. 5445 Highland Park Drive, St. Louis, MO, 63110, USA;
ijacobs@pctincusa.com
23
An apparatus was assembled which was designed to spray dry gram to sub-gram quantities
of active pharmaceutical ingredients in solution for formulation development. The idea
was that existing commercial equipment produced product at very low yields and added
thermal stress with severe limitations on achievable particle size. With such small
quantities atomized, some consideration had to be given to simplicity and thoroughness of
cleaning without excessive effort. Lastly, the equipment should be capable of atomization
of molten feeds (spray chilling) and atomization to achieve a fairly uniform particle size
distribution to reduce heat stressing normally required in drying the larger particles in an
atomized distribution. The apparatus was assembled with necessary controls and
temperature monitoring. It has been found to produce yields of approximately 85 to 90%
based on collected product vs. atomized solids and at a size distribution consistently of
about d90/d10 of 2.2. The atomization of feed parameters can be adjusted to produce
particles ranging from approximately 5 microns to 100 microns. It is capable of spray
chilling. The equipment has been used for the spray drying of active ingredients in solution
with various polymers to prepare amorphous matrices for preparation of enhanced
bioavailability formulations. Also, atomization conditions can be varied to produce
smooth or porous surface morphologies. Solvents including water, acetone, methylene
chloride and even glacial acetic acid have been used. Proteins and live bacteria have been
spray dried with good retention of activity or viability. Hard to dry sugars have been dried
successfully and free-flowing product achieved. The technique has also been used more
recently to achieve high dilutions of extremely active pharmaceutical ingredients to assure
one of homogeneous dilution of the formulation. Lastly, the ultrasonic atomizer has been
adapted with a concentric tube for production of true core/shell morphologies by this spray
drying technique.
C1 – Contributed Paper
ALL-DRY ENCAPSULATION OF FINE PHARMACEUTICS FOR
CONTROLLED DRUG RELEASE
Kenneth K. S. Lau and Karen K. Gleason, Department of Chemical
Engineering, Massachusetts Institute of Technology, 77 Massachusetts
Avenue, Cambridge, MA 02139, USA; klau@mit.edu
24
Current methods for encapsulating pharmaceutical powders are prone to particle
agglomeration as a result of strong binding forces from liquid bridges which form during
drying of the polymer solution that is applied to the particles. This condition becomes
increasingly severe as particle dimensions go below 100 µm. To circumvent this limitation,
47
Oral Abstracts
we present an all-dry encapsulation technology, initiated chemical vapor deposition
(iCVD), that enables fine pharmaceutical powders well below 100 µm in size to be coated
with controlled release polymer formulations. iCVD enables polymers with stoichiometric
compositions to be made in a CVD environment, unlike plasma CVD, which tends to lead
to undesired crosslinking and loss of chemical functionality. iCVD combines
polymerization and coating in a single efficient step, achieving individual particle layering.
We present results on methacrylic acid copolymer systems for modifying the release of
ibuprofen microcrystals down to 25 µm in size. FTIR and XPS reveal the composition of
these polymers, demonstrating the tunability of copolymer ratios. SEM show the
morphology and conformality of the coatings, demonstrating coating without particle
agglomeration. Controlled release studies evidence delayed release based on pH
conditions, demonstrating enteric release of the core material. iCVD kinetic modeling
reveals a surface-driven polymerization that is similar to bulk phase free radical
polymerization. The iCVD process is believed to involve the delivery of monomer and
initiator vapors into the coating reactor; thermal activation of the initiator to create primary
radicals; diffusion and adsorption of the primary radicals and monomer onto the surface;
and finally surface polymerization via initiation, propagation and termination to yield a
polymer encapsulation layer on the surface.
C1 – Keynote Paper
DRUG, PROTEIN, AND DNA DELIVERY WITH
GLUTATHIONE-MEDIATED RELEASE USING GOLD
NANOPARTICLES
Vincent M. Rotello, Department of Chemistry, University of Massachuetts,
Amherst, MA 01003 USA; rotello@chem.umass.edu
25
Monolayer-protected gold nanoparticles provide effective vectors for the delivery of drugs
and biomolecules. The ability to attach targeting functionality presents a means of
delivering these carriers to target organs and tissues. Additionally, the capability of tuning
surface properties provides systems that are rapidly internalized by cells, with intracellular
targeting possible through the use of appropriate functionality. In addition to their ability to
be functionalized in modular fashion, gold nanoparticles provide a tunable method for
payload release. Glutathione (GSH) is present in low micromolar concentrations
extracellularly. Intracellular GSH concentrations, however, range from 1-10 millimolar.
This dramatic increase in GSH concentration within the cell provides a novel means for
release: GSH can displace thiol functionality from the particle surface. This displacement
process can be used directly to release drugs and prodrugs. Moreover, the addition of
anionic GSH can be used to change the surface potential of cationic particles, providing an
effective means for release of electrostatically-bound DNA and proteins. All of these
release processes are tunable via control of the monolayer structure, with release rate
correlating with monolayer length..
48
Oral Abstracts
D1 – Keynote Paper
SYNTHESIS AND CHARACTERIZATION OF NANO AND
MICRON-SIZED PARTICLES OF NARROW SIZE DISTRIBUTION FOR
MEDICAL IMAGING APPLICATIONS
S. Margel, T. Lublin-ennenbaum, A. Galperin, B. Perlstein, O. Ziv and M.
Tsubery, Bar-Ilan University, Ramat-Gan 52,900, Israel;
shlomo.margel@mail.biu.ac.il
26
Polystyrene (PS) microspheres of narrow size distribution were prepared by dispersion
polymerization. These microspheres were then coated with silica and/or magnetite/silica
thin films. Uniforms hollow silica and hollow silica/magnetite micron-sized particles were
prepared by burning off the silica/PS and silica/magnetite/PS composite particles,
respectively. The potential use of these air-filled hollow particles for ultrasound imaging
have been demonstrated. Maghemite nanoparticles (10-100 nm) of narrow size distribution
were formed by nucleation and the growth of thin maghemite films onto desired nuclei.
The surface of the maghemite nanoparticles was then coated with dextran, followed by
crosslinking with divinyl sulfon. The residual double bonds of the divinyl sulfon have been
used for covalent binding of various bioactive reagents. The potential in vitro and in vivo
use of the non-conjugated and conjugated maghemite nanoparticles for MRI imaging have
been demonstrated. Polymeric nano and micron-sized particles containing high loading of
iodine were formed by emulsion and dispersion polymerization, respectively of acrylate
monomers containing iodine. The potential in vitro and in vivo use of these particles for
x-ray imaging has also been demonstrated.
D1 – Invited Paper
DYNAMIC NMR CHARACTERIZATION OF NANOPARTICLES FOR
MEDICAL IMAGING APPLICATIONS
Yuzhuo Li and Fadwa Odeh, Center for advanced Materials Processing,
Department of Chemistry, Clarkson University, Potsdam, NY 13699, USA;
yuzhuoli@clarkson.edu
27
Particle size is crucially important in determining the usefulness of a nanoparticle system
for medical imaging applications. Until now, the particle size of a liposome or lipid
nanoparticle systemis typically determined using a light scattering method. The method
often suffers from interferences from air bubbles, dusts, and unrelated particles. Although
the NMR pulsed field gradient (PFG) experiments are known to yield self-diffusion
coefficient for micelles and other particulate matters, the application of this technique to
vesicle and lipid systems has been limited due to the rigid nature of the lipid bilayer which
usually does not give well-defined NMR signals for PFG experiments. This study shows
that the polyethylene oxide chains on a pegylated lipid could serve as an excellent tracer to
measure the self-diffusion coefficient via PFG method. In addition, liposomes or lipid
nanoparticles containing a hydrotrope also give adequate signal from the lipid for PFG
experiments due to the increased flexibility of the lipid molecules. In addition to particle
size, PFG-NMR is also used to determine the extent of association of a hydrotrope with the
liposome bilayer.
49
Oral Abstracts
D1 – Invited Paper
PERFLUOROCARBON NANOBUBBLES AS DIAGNOSTIC AND
THERAPEUTIC AGENTS
Terry Matsunaga, Evan Unger, ImaRx Therapeutics, Inc., 1635 East 18th St.,
Tucson, Arizona 85719, USA; tmatsunaga@imarx.com
28
Perfluorocarbon gas-water interfaces are exquisitely efficient at reflecting ultrasound
waves. As such, they can act as excellent vascular contrast agents. Currently, there are two
bubble products that are commercially available as echocardiographic contrast agents.
Moreover, in the presence of clinical ultrasound frequencies on the order of 1 – 10 MHz,
gas bubbles ranging in size 5 μm or less, are subject to oscillations and cavitation. This
cavitational effect can be used as a therapeutic modality to aid in the dispersion of vascular
thrombi. We refer to this as SonoLysis® Therapy. We have combined diagnostic and low
mechanical index therapeutic ultrasound to both detect regions of thrombotic occlusion
and to affect recanalization of those vessels. Work has been performed to demonstrate the
physical phenomenom of bubble cavitation as well as preclinical studies to confirm
thrombus dispersion. Pre-clinical studies have focused upon the efficacy of Sonolysis in a
series of applications. In addition, we will provide insight into the potential of SonoLysis
therapy for the treatment of vascular occlusions.
D1 – Contributed Paper
MOLECULARLY IMPRINTED NANPARTICLECLES FOR
ANALYTICAL AND PREPARATIVE SEPARATION OF AMINO ACID
DERIVATIVES
Marc Herold, C. Gruber, M. Herold, A. Weber, M. Dettling, S. Sezgin, Günter
E. M. Tovar, H. Brunner, Institute for Interfacial Engineering (IGVT),
University of Stuttgart & Fraunhofer Institute for Interfacial Engineering and
Biotechnology (IGB), Nobelstr. 12, D-70569 Stuttgart, Germany;
marc.herold@igb.fraunhofer.de
29
Molecular imprinting is a template polymerization which produces artificial binding sites
in polymers. Their specific cavities can be used for molecular recognition reactions
mimicking the antibody-antigen interaction, but now with a completely synthetic system.
Nowadays particulate MIP’s with a defined morphology and of colloidal size open new
applications for these artificial receptor material. In a new approach, we synthesized MIP’s
as nanoscopic spheres. A variety of highly crosslinked copolymer networks, e.g.
poly(methacrylic acid)-co-(ethylene glycol dimethacrylate) nanoparticles were prepared
by miniemulsion polymerization in presence of a molecular template (e.g. amino acid
derivatives L- or D-boc-phenylalaninanilid) with a yield of (98 ± 2) %. Coagulate-free and
stable latexes were obtained. The prepared polymer colloids are in the size range of 50 –
300 nm. The efficiency of the imprinting process was quantified by ligand binding
experiments using UV/Vis and HPLC. The nanoscopic molecularly imprinted polymers
(MIP’s) allowed for the first time for an examination of the non-covalent interaction
50
Oral Abstracts
between the synthetic receptor and various ligands by microcalorimetry. The interfacial
preparation method introduced here now opens the way to imprinting more complex
templates such as peptides or proteins. The preparation and the use of the colloidal MIP’s,
e.g. as the surface coating of an optical waveguide sensor, and as a selective layer in a
composite membrane are presented.
D1 – Invited Paper
NANOMAGNETIC PARTICLES IN RAPID DIAGNOSTICS
Yousef Haik, Department of Mechanical Engineering, United Arab Emirates
University, Al Ain, UAE and Center for Nanomagnetics and Biotechnology,
Florida State University, Tallahassee, FL 32310, haik@eng.fsu.edu, Reyad
Sawafta, Quartek Corporation, 4180 Piedmont Parkway, Greensboro, NC,
27410, USA; rsawafta@quartekcorp.com
30
Today, with increase emphasis in cost-effective decision-making at the point of care, first
responders are in need for rapid and effiecient diagnsotic devices. The use of magnetic
immunoassays has grown considerably in recent years. This study identifies a simple
process that uses nanomagnetic particles to quickly condcut an anlysis, under field
conditions, for detection of analytes. The process has been utilzed for rapid diagnostics of
acute mycorial infarction (AMI) at the point of care and for diagnosis of food born
pathogens. The magnetic immunoassya takes advantgae of multiple epitopes that are
found on the target. On ne epitope a magnetic particle is attached. On another epitope a
colorimetric marker is attached. Magnetic nanoparticles of different classes of magnetic
compoistions were prepared. The compositions include, Fe-Zn-Fe, Fe-Gd-Zn, Fe-Nd-B,
and Ni-Cu. Magnetic moment measurments showed a substantial increase when compared
with the iron oxide particles. These particles were then coated with bovine serum albumin.
The surface of the coated particles was then modified to couple with the target. Site speific
antibodies were used to isolate cardiac protiens (Troponin, Myoglobin, FABP) for the AMI
daignosis and to isolate food born pathogens (E. coli and S. enteritidis). A secondary
antibody with a colorimetric marker (AP or HRP) was attached to the analyte. Different
serial concentration of cardiac markers (0-700 μg/L) were used in forming the conjugate.
The resulted color intensities were corrolated to the amount of the cardiac marker used in
the conjugate. The experimental results also showed that HRP perfromed better than that
of AP particularly at high concentrations of cardiac markers. Serial dilutions of E. coli
O157:H7 concentrations in buffer samples were used. Both HRP and AP conjugates were
used. A higher sensitivity of the assay was observed when using the HRP compared to AP
labeled antibodies. The specificity of the assay for selecting E. Coli in the presence of
other pathogen (S. enteriditis) was also tested. The assay specifically identified E. Coli and
it yielded negative results for the sample containing S. enteriditis as well as for the blank
sample. The nanomagnetic immunoassay has showed a senstivity of detecting the
presence of a single bacterium in a meat spiked with E. coli and S. enteritidis. E. coli
O157:H7 and S. enteritidis concentrations in buffer and meat samples were confirmed by
plating 0.1 ml sample onto plate count agar. For the E. coli O157:H7 samples, the highest
dilution contained approximately 6 cells/ml of buffer and 1 cell/g of meat, respectively. For
the S. enteritidis samples, the highest dilution contained approximately 9 cells/ml of buffer
51
Oral Abstracts
and 1-2 cell/ g of meat, respectively. The process of detection for both the cardiac markers
and pathogens was performed in few minutes.
D1 – Invited Paper
REAL-TIME VISUALIZATION OF NANO-LIPOSOMAL DELIVERY
INTO PRIMATE BRAIN BY MAGNETIC RESONANCE IMAGING
Krystof S. Bankiewicz, Michal T. Krauze, John R. Forsayeth, Department of
Neurological Surgery, Brain Tumor Research Center, University of California
San Francisco, CA; Charles O. Noble, Daryl C. Drummond, Dimitri B.
Kirpotin and John W. Park, Division of Hematology-Oncology, University of
California San Francisco, CA; Peter J. Dickinson, Robert Higgins, Rick
LeCouteur, Department of Surgical and Radiological Sciences, University of
California, Davis, CA; kbank@itsa.ucsf.edu
31
Liposomes loaded with Gadoteridol (GDL), in combination with convection-enhanced
delivery (CED), offer an excellent option to monitor CNS delivery of therapeutic
compounds with MRI. In our studies, we investigated possible clinical applications of
liposomes to the treatment of brain tumors. In our study, up to 700 μl of
Gadoteridol/rhodamine-loaded liposomes were distributed in putamen, corona radiata and
brainstem of non-human primates. Distribution was monitored by real-time MRI
throughout infusion procedures, which allowed accurate calculation of volume of
distribution within anatomical structures. We found that different regions of the brain gave
various volumes of distribution when infused with the same volume of liposome.
Furthermore, we investigated multiple real-time infusions in the same regions for
reproducibility, and possible long-term changes in primate brain due to liposome
convection. In parallel with the primate experiments, we performed CED of
nano-liposomal therapeutics (Ls-CPT-11, Doxorubicin) into rodent brain tumor
xenografts. Therapeutic liposomes mediated metronomic chemotherapy to brain tumors as
controlled release could be detected up to 40 days after single delivery. These experiments
also showed tremendously increased survival, and a very broad safety profile. Based on
these findings, real-time delivery of therapeutic liposomes was initiated in canines with
spontaneous brain tumors. Initial findings suggest that spontaneous tumors are amenable
for CED of liposomes. MRI is highly accurate in monitoring distribution, thereby avoiding
unwanted distribution into CSF. This work underlines the importance of monitoring drug
delivery to CNS, and enables accurate delivery of drug-loaded liposomes to specific brain
regions with a standard MRI procedure. Real-time CED of liposomes is a promising drug
delivery technique for brain pathologies in which localized delivery of therapeutic agents
is indicated.
D1 – Contributed Paper
CONTROLLED CLUSTERING OF SUPERPARAMAGNETIC
NANOPARTICLES USING BLOCK COPOLYMERS : DESIGN OF NEW
CONTRAST AGENTS FOR MAGNETIC RESONANCE IMAGING
Jean-François Berret, Matière et Systèmes Complexes, Université Denis
32
52
Oral Abstracts
Diderot, Paris-VII, 140 rue de Lourmel, F-75015 Paris, France, and Olivier
Sandre, Laboratoire Liquides Ioniques et Interfaces Chargées, Université
Pierre et Marie Curie, Paris-VI, 4 place Jussieu, F-75252 Paris, France;
jean-francois.berret@ccr.jussieu.fr
During the past years we have investigated the complexation between nanocolloids and
oppositely charged polymers. The nanocolloids examined were ionic surfactant micelles
and inorganic oxide nanoparticles. For the polymers, we used homopolyelectrolytes and
block copolymers with linear and comb architectures. In general, the attractive interactions
between oppositely charged species are strong and as such, the simple mixing of solutions
containing dispersed constituents yield to a precipitation, or to a phase separation. We have
developed means to control the electrostatically-driven attractions and to preserve the
stability of the mixed solution. With these approaches, we designed novel core-shell
nanostructures, e.g. as those obtained with polymers and iron oxide superparamagnetic
nanoparticles (Berret et al., JACS (2006)). In this presentation, we show that electrostatic
complexation can be used to tailor new functionnalized nanoparticles and we provide
examples related to biomedical applications in the domain of contrast agents for Magnetic
Resonance Imaging.
D1 – Invited Paper
MULTILAYERED NANOPARTICLES: CHARACTERIZATION AND
BIOANALYTICAL USE
Karin D. Caldwell, Department of physical and analytical chemistry, Box
577, Uppsala University, SE-75123 Uppsala, Sweden;
karin.caldwell@ytbioteknik.uu.se
33
The attachment of biologically active proteins to solid surfaces requires utmost care to the
manner in which the linking of these often fragile macromolecules is carried out. Issues of
concern relate to structural protection, but also to the presentation of reactive features to the
environment. One attractive way of addressing these issues is to attach the molecules to
solid particles in the 100-250 nm size range through the intermediary of a system of surface
linked tethers. These structures protect the protein from direct contact with the substrate
while allowing it substantial freedom of motion. Particularly in the design of biosensor
systems there is a frequent need to attach not only single proteins but also more complex
combinations of molecules which, in a cascade fashion, help to amplify a desired signal. In
order to maintain compositional control over such composite systems it is desirable to
exactly manage the concentrations and activities of all features bound to the surface. It is in
this respect that immobilization via a cocktail of differentially activated tethers becomes
particularly attractive. The utilization of this strategy will be exemplified by way of a
bioluminescence based sensor chip, containing localized islands of immobilized
nanoparticles decorated both with capture antibodies and with the signal generating
enzyme firefly luciferase. As the analyte binds the antibody it is made to produce ATP that
rapidly diffuses the short distance to the neighbouring enzyme, which it binds and assists in
generating a light pulse. The exact surface concentrations of tethers as well as active
biomolecules are determined by sedimentation FFF, in a series of analyses that reveal the
detailed construction of the surface coating.
53
Oral Abstracts
E1 – Keynote Paper
COMPARATIVE PERFORMANCE OF TRANSFECTION COMPLEXES
DERIVED FROM A FAMILY OF BISVINYL ETHER CATIONIC LIPIDS
David H. Thompson, Jeroen Van den Bossche, Department of Chemistry,
Purdue University, 560 Oval Drive, West Lafayette, IN 47907, USA;
davethom@purdue.edu
34
The development of synthetic vehicles for gene delivery that can rival the efficiency of
viral vectors is an unmet challenge in non-viral vector design. Of the many known barriers
to efficient transfection, control over intracellular trafficking and release from acidic
endosomal compartments are among the most poorly understood steps in this multistep
process. We report the synthesis and performance of a series of structurally-related
acid-labile cationic lipid transfection agents that have been designed to degrade within
acidic endosomes and promote endosomal escape by permeabilizing the endosomal
membrane via detergent action of the lipid hydrolysis products. These cationic lipid
derivatives contain vinyl ether-linked lipid chains and diethylenetriamine headgroups that
were designed to be more responsive than the prototype BCAT lipid that was previously
reported by this laboratory. The synthesis, complexation behavior, intracellular uptake,
and expression levels of these materials will be described.
E1 – Invited Paper
LIPIDIC CUPIC PHASES: APPLICATIONS IN MEMBRANE PROTEIN
CRYSTALLOGENESIS AND IN UPTAKE AND DELIVERY
Martin Caffrey, Department of Chemical and Environmental Sciences,
Plassey Park, University of Limerick, Limerick, Ireland; martin.caffrey@ul.ie
35
One of the primary impasses on the route that eventually leads to membrane protein
structure through to activity and function is found at the crystal production stage.
Diffraction quality crystals, with which an atomic resolution structure is determined, are
particularly difficult to prepare currently when a membrane source is used. The reason for
this lies partly in our limited ability to manipulate proteins with hydrophobic/amphipathic
surfaces that are usually enveloped with membrane lipid. More often than not, the protein
gets trapped as an intractable aggregate in its watery course from membrane to crystal. As
a result, access to the structure and thus function of tens of thousands of membrane proteins
is limited. The health consequences of this are great given the role membrane proteins play
in disease; blindness and cystic fibrosis are examples. In contrast, a veritable cornucopia
of soluble proteins have offered up their structure and valuable insight into function,
reflecting the relative ease with which they are crystallized. There exists therefore a
pressing need for new ways of producing crystals of membrane proteins. A
novel approach that holds promise makes use of the lipidic cubic phase. In this
presentation I will describe the method and our progress in understanding how it works at a
molecular level. The practicalities of implementing the method in low- and
high-throughput modes will be examined. Transport properties of the cubic phase are
critical to the crystallization process and have been explored from this perspective but also
54
Oral Abstracts
with regard to their possible use in updake and delivery applications. Supported in part by
Science Foundation Ireland (02-IN1-B266), the National Institutes of Health (GM61070,
GM075915), and the National Science Foundation (DBI9981990).
E1 – Invited Paper
SPATIALLY ADDRESSABLE PROTEIN ARRAYS BASED ON
PROTEOLIPOSOME SELF-ASSEMBLY INTO MICROWELLS
Alexander Couzis, Charles Maldarelli, Lane Gilchrist, Nikhil Kalyankar,
Shyam Vaidya, Gerson Aguirre, Dept. of Chemical Engineering, The City
College of New York, NewYork, NY 10031;couzis@ccny.cuny.edu
36
Protein microarrays - high throughput diagnostic methods in which proteins are arrayed in
spots on a surface and screened in one step against a solution of potential binding partners
– has emerged as the primary tool in mapping the protein binding interactions of the
proteome. This paper outlines a research program focused of the development of a new
platform for a protein array, which, extends current technologies and can represent the next
generation in protein microarray technology. The array platform addresses two issues in
current protein array technology. The first is further miniaturization: Current technologies
use fluid spotting to array spots 102 microns in diameter on surfaces with active areas of the
order of millimeters by millimeters to generate up to thousands of spots per array. The
second is the inability to display functioning cell membrane surface receptors;
while antibodies and small molecule ligands can easily be spotted onto a surface, cell
membrane proteins require a lipid environment to maintain functionality. The inclusion of
membrane proteins is particularly significant because these proteins control cell signaling
pathways. Our array platform uses 500 nm – 1000nm in diameter liposomes to sequester
and display cell membrane proteins (proteoliposomes) and quantum dot (QDs) encoded
beads to label the liposomes with a fluorescent label and provide for spatial addressability.
Sequestering the proteins in the liposome bilayer retains their biological activity and
the barcoding in beads allows assaying on the nanoscale. Mixtures of the proteoliposomes,
each with a different protein and corresponding barcode, are then arrayed on a surface in
wells separated by 500-3000 nm. For an active area of 500 μm x 500 μm, upwards of 106
registries can be assembled. In this formats, GPCR membrane proteins and glycolipids will
be employed to demonstrate the viability of the arrays, using fluorescence detection with
imaging microscopy.
E1 – Invited Paper
USE OF NOVEL INTRALIPOSOMAL STABILIZATION STRATEGIES
FOR FORMING HIGHLY STABLE AND LONG CIRCULATING
NANOLIPOSOME CONSTRUCTS FOR CAMPTOTHECINS AND VINCA
ALKALOIDS
Daryl C. Drummond, Mark E. Hayes, Charles O. Noble, and Dmitri B.
Kirpotin, Hermes Biosciences, 61 Airport Blvd, South San Francisco, CA; and
John W. Park, University of California at San Francisco, San Francisco, CA;
drummond@hermesbio.com
37
55
Oral Abstracts
Controlling the rate of drug release from liposomal carriers is essential for optimum drug
delivery. We have developed a novel nanoliposome construct encapsulating either
CPT-11 (irinotecan) or vinorelbine (VRL) with a high degree of drug loading efficiency
and in vivo retention. Using a modified gradient loading method featuring a sterically
hindered amine with highly charged, multivalent anionic trapping agents, either polymeric
(polyphosphate) or non-polymeric (sucrose octasulfate), liposomes were capable of
entrapping CPT-11 at extremely high drug-to-lipid ratios (> 800 g CPT-11/mol
phospholipid) and retaining encapsulated drug in vivo with a half-life of drug release in the
circulation of 56.8 h. The release rate (t1/2 = 1.8-27.2 h) of vinorelbine from the liposome
could be improved by either modifying the chemical nature of the trapping agent or by
altering the concentration of drug loaded into the liposomes, with liposomes prepared
using sucroseoctasulfate displaying the longest half-life in the circulation (9.3 h) and in
vivo retention in the nanoparticle (t1/2=27.2 h). CPT-11 was also protected from hydrolysis
to the inactive carboxylate form and from metabolic conversion to SN-38 while
circulating. The maximum tolerated dose in normal mice was determined to be 80 mg/kg
for free CPT-11 and >320 mg/kg for nanoliposomal CPT-11. The acute toxicity in normal
mice was not increased upon encapsulation of vinorelbine in liposomes, with an MTD of
17.5 mg VRL/kg for free vinorelbine and 23.8 mg VRL/kg for nanoliposomal vinorelbine.
Nanoliposomal CPT-11 demonstrated markedly superior efficacy when compared to free
CPT-11 in human breast (BT474) and colon (HT29) cancer xenograft models, while
nanoliposomal vinorelbine displayed improved activity in a wide range of lung, colon, and
breast cancer xenograft models. These studies shows that intraliposomal stabilization of
CPT-11 or VRL using a polymeric or highly charged, non-polymeric polyanionic trapping
agent results in strikingly active antitumor agents with low toxicity.
E1 – Contributed Paper
COMPARATIVE PERFORMANCE OF TRANSFECTION COMPLEXES
DERIVED FROM A FAMILY OF BISVINYL ETHER CATIONIC LIPIDS
David H. Thompson, Jeroen Van den Bossche, Department of Chemistry,
Purdue University, 560 Oval Drive, West Lafayette, IN 47907, USA;
davethom@purdue.edu
38
Microvascular endothelial cells are relevant targets for targeted liposome mediated drug
delivery, because of their involvement in pathophysiological processes such as chronic
inflammatory disease. Furthermore endothelial cells are direct accessible for substances
transported by the blood. The heterogeneity of the endothelium with respect to appearance
and function allows for disease specific drug delivery approaches. E.g., activated
endothelial cells present in areas of inflammation selectively (over)express various
adhesion molecules. Among these, E-selectin is solely expressed by activated endothelial
cells while it is absent in non-diseased organs. Therefore E-selectin is an ideal target to
deliver anti-inflammatory drugs into activated endothelial cells. The aim of the study was
to develop immunoliposomes targeted to E-selectin on activated endothelial cells for
intracellular delivery of drugs for the treatment of inflammatory diseases. We prepared
immunoliposomes containing dexamethasone, using anti-E-selectin IgG as a homing
56
Oral Abstracts
device. In TNFα activated human umbilical vein endothelial cells, association of
anti-E-selectin immunoliposomes was 20 fold higher than in non-activated endothelial
cells. This association could be blocked by excess of free anti-E-selectin but not by control
IgG, demonstrating specificity of the interaction. Confocal laser scanning microscopy
demonstrated that the immunoliposomes were endocytosed via a clathrin mediated
pathway. In vivo, in a mouse model of anti-glomerular basement membrane induced
glomerulonephritis, injection of dexamethasone containing anti-E-selectin
immunoliposomes revealed specific uptake in the kidneys as compared to control
liposomes. Within the kidney the anti-E-selectin immunoliposomes were located in the
diseased glomeruli, corresponding to the glomerular expression of E-selectin in this model.
The immunoliposomal delivery of dexamethasone into the diseased glomeruli resulted
locally in a significant downregulation of inflammation related genes. Systemic
hyperglycemia induction seen with free dexamethasone treatment was absent in the
dexa-immunoliposome treated group. These data demonstrate the feasibility of selective
delivery of anti-inflammatory drugs by immunoliposomes into disease-activated
endothelium to exert local pharmacological effects.
E1 – Invited Paper
TRM-484, STEROID INCLUDED IN LONG CIRCULATING CATIONIC
LIPOSOMES ACTIVELY TARGETING INFLAMMATORY TISSUES
Junji Kimura, Katsumi Morimoto, Shinichi Kaneda, Masaharu Miyajima,
Hiroaki Kasukawa, TERUMO Corporation R&D Center, 1500 Inokuchi,
Nakai-machi, Ashigarakamigun, Kanagawa, 259-0151 Japan;
junji_kimura@terumo.co.jp
39
We have been developing a novel liposome actively targetable to diseased cells without
losing a long-circulating ability in the blood. Our novel active targeting factor, TRX-20
(3,5-dipentadecyloxybenzamidine hydrochloride), has been reported to interact with some
kind of chondrotin sulfate proteoglycans (CSPGs) on the subendothelial cell surfaces
under certain diseases such as inflammation, but not with heparan sulfate proteoglycans.
However, to make satisfy both long-circulating and selective targeting, an optimal
composition ratio of polyethylene glycol and TRX-20 on the liposomal surface was
confirmed to be important. We are developing a prednisolone-encapsulated liposome
(TRM-484) using this technology mentioned above. In this presentation, we would show
the mechanism of action and its pharmacological advantages with some in vitro and in vivo
studies. In summary, TRM-484 bound to cultured synovial cells derived from RA patients
via mediating CSPGs on these cell surfaces, introduced into the cell inside and then
released prednisolone. Also in the rat arthritic model TRM-484 localized in the synovial
lining cells, but not in the normal joint tissues. Effective dose of prednisolone with this
liposomal formulation could be reduced by 1/10 of oral dose. Such local effect and dose
reduction are expected to decrease side effects due to lower systemic exposure of
prednisolone. Currently TRM-484 is in a phase 1 study.
57
Oral Abstracts
E1 – Invited Paper
DNA BASED HYDROGELS, LIPOSOMES AND NANOBARCODES
Dan Luo, Soong Ho Um, Jung Bum Lee, Nokyoung Park, Sang Kwon
Dept. of Biological and Environmental Engineering
Cornell University, Ithaca, NY 14853, USA; DL79@cornell.edu
40
DNA can be engineered as a generic instead of a genetic material -- the genetic
information-coding property of DNA can be completely and purposely ignored. Instead, by
taking advantage of nanoscale, molecular biology tools (including enzymes) we have
employed DNA as a true and novel polymer. Branched, networked, and dendritic DNA has
been fabricated as additional building blocks for novel materials. In particular, we have
made DNA based hydrogels in a variety shapes and sizes, from centimeter to nanometer,
and from a complicated pattern (“Cornell”) to spherical, microdroplets. These DNA gels
are water soluble, biocompatible, biodegradable and most importantly can encapsulate
drugs and even live cells in situ, eliminating the drug loading step and also avoiding
denaturing conditions that are typical in most hydrogel-based, controlled-release systems.
The efficiency of encapsulation of the DNA gels has reached close to 100%. DNA
hydrogels will have great potential for controlled drug delivery, tissue engineering, 3D cell
culture, cell transplant therapy, and other biomedical applications. We have also created
DNA-based, anisotropic dendrimers that can be tagged with a variety of chemical moieties.
The process is robust and totally controlled. The anisotropic structures were also very
stable. Although we demonstrated anisotropic DNA dendrimers with only fluorescent tags
(which were used as DNA based nanobarcodes), the procedures can be easily extend to
almost any chemical moieties as long as they can be conjugated to DNA strand. Thus it is
possible to use DNA as framework to create anisotropic materials for a variety of
applications such as a barcode system for molecular detection and a heterogeneous drug
delivery system with different drugs along with specific targeting molecules. In addition,
we have also created DNA-liposomes from DNA dendrimers, The dendritic DNA
components embedded in these amphiphiles offered not only greater control over general
morphology, but also a unique method for tracking the liposomes’ core-shell
nanostructures via a simple labeling with DNA and lipid specific fluorescent dyes. It is
expected that DL-DNA-lipid amphiphiles and DNA-liposomes will become new tools for
designing and synthesizing novel, drug delivery materials and for tracking self-assembling
processes.
F1 – Invited Paper
CHARACTERIZATION OF MAGNETIC NANOPARTICLES USING
QUADRUPOLE MAGNETIC FIELD-FLOW FRACTIONATION
P. Stephen Williams, Francesca Carpino, and Maciej Zborowski, Cleveland
Clinic, Lerner Research Institute, Department of Biomedical Engineering,
9500 Euclid Avenue, Cleveland, OH 44195, USA; willias3@ccf.org
41
Field-Flow Fractionation (FFF) is an analytical scale separation and characterization
technique for macromolecules and particles (from ~0.01 to 100 μm in diameter). The
58
Oral Abstracts
technique was conceived by Cal Giddings in 1966. It is a separative elution technique,
similar to chromatography, in which different components of a small sample elute from a
separation channel at different times. Whereas chromatography exploits differences in
partition between the mobile and stationary phases to separate sample components as they
are carried along a column, FFF separation is achieved within the mobile phase alone. The
separation device takes the form of a thin, parallel-walled channel, across the thickness of
which is applied a field of some type. Particles that interact strongly with the field are
confined to thin zones adjacent to the wall where fluid velocity is low, and they elute more
slowly than particles which interact less strongly with the field. Furthermore, the
quantitative theoretical foundation of FFF allows the determination of the strength of
interaction of particles with the field as a function of their elution time. The nature of the
applied field determines the sample property that is characterized. Our approach to
magnetic FFF (MgFFF) uses the radially symmetric magnetic field generated by a
quadrupole electromagnet. A thin helical channel exploits the quadrupole field efficiently.
The field strength is gradually reduced during sample elution in order to elute very
polydisperse samples. MgFFF has been used to characterize magnetic nanospheres used
for immunospecific labeling of biological cells for magnetic separation. Samples of
different production lots were kindly supplied by BD Biosciences Pharmingen. The
samples were eluted under a range of different mobile phase flow rates and programmed
field decay conditions. Distributions in magnetite content were determined for the sample
lots supplied. The method appears to be a useful technique for quality control purposes.
F1 – Invited Paper
COLLOIDAL STABILITY OF EMULSIONS AND NANOPARTICLES IN
PHARMACEUTICS
Hélène Dihang, Pascal Bru, Gérard Meunier, Formulaction, 10 impasse
Borde, Basse 31240 L’Union, France; and Patrick Snabre C.R.P.P., avenue
Albert Schweitzer, 33600 Pessa, France; dihang@formulaction.com
42
The world of drug delivery is getting every day more efficient with new product forms,
which are directly targeting the deficient organs. Colloidal systems such as emulsions
(simple or multiple) or nanoparticle suspensions are now widely used as drug carriers or
nutritional solutions in this respect. These new product forms allow better targeting and
assimilation for the patient, and give rise to new solutions for the drug designers. However,
the stability of these inherently unstable colloidal systems makes them complex to
formulate and study. Despite the existence of models and increasing knowledge on
physical chemistry to help the formulator to tend towards more stable formulations, he
cannot take the risk to select an industrial formula for its sole end-use properties without
testing the stability experimentally, when an unstable formulation can risk the life of the
patient he is trying to cure. Therefore, the companies developing instruments have worked
in collaboration with the physical chemists, from industry and research, to develop new
techniques of analysis for either predicting the stability of these mixtures, or reducing
times of ageing tests. These techniques, although very powerful, require a good knowledge
of measurement to interpret the results. This presentation aims to review the main
techniques available to monitor the physical stability of colloidal systems for
pharmaceutical applications.
59
Oral Abstracts
F1 – Contributed Paper
PARTICLE SIZE ANALYSIS: COMPARTIVE RESULTS FROM
SEVERAL TECHNIQUES.
Frank M. Etzler and Richard Deanne. Boehringer-Ingelheim
Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, CT 06877, USA;
fetzler@rdg.boehringer-ingelheim.com
43
Particle size analysis is important to a number of industrial processes and influences the
performance of many products. In the context of the pharmaceutical industry particle size
affects the performance, for instance, of inhalable formulations and the dissolution rate of
poorly soluable compounds. Processes relying on powder flow are also affected by particle
size and partticle size distribution. Particle size analysis is difficult for a number of
experimental and philosophical reasons. Particle size unlike many often experimentaly
measured quantities is ill defined in many instances. The size of spherical particles can be
expressed as a single number – the radius or diameter. In contrast, particles of complex
geometry particularly disks, flakes and needles cannot be completely described using a
single number. Many particles are also significantly cohesive and may not disperse into
parimary particles on a least some kinds of particle sizing equipment. The dispersion
charateristics of commercially available equipment is not hydrodynamically defined. Laser
diffraction instruments have found almost Procrustean use in the pharmaceutical industry
principally because they are relatively easy to use. The theoretical basis for the
construction of such instruments is complex and in many senses incompletely
implemented on commercially avaliable for a number of technical reasons. One
consequence is that in many instances the response to changes in subpopulations particles
may not be reflected by the instrument in a linear manner resulting either in an
underestimate or overestimate of the change in the subpopulation. In this work compartive
performance of serveral instruments is investigated. The influence of powder properties
and instrument design is ilustrated. Recommendations for future work are also made.
F1 – Invited Paper
PARTICLE SIZE AND SHAPE CHARACTERIZATION OF NANO- AND
SUBMICRON SUSPENSIONS
Arjen Tinke, Johnson & Johnson Pharmaceutical R&D, Turnhoutseweg 30,
B-2340 Beerse, Belgium; atinke@prdbe.jnj.com
44
Nanonization and micronization of highly (water) insolible compounds by means of wet
milling is generally applied in function of a modication of the in-vivo release profile of
active pharmaceutical ingredients (API). More precisely, the technology is used as basis
for the pharmaceutical development of various types of dosage forms, such as for example
sustained release and depot formulations. Since the dissolution of the particles is a
dominant factor in the release mechanism of these drugs, it is an absolute necessity to
characterize the particles in terms of their morphology (or shape) and particle size
distribution (PSD). An adequate characterization of the shape and size distribution will
enable the evaluation of the dosage form in terms of release profile, burst effect, Ostwald
60
Oral Abstracts
ripening, etc. In practise, the size distribution characterization of nano- and submicron
particulate systems is often far from straightforward, and the different analytical
techniques easily lead to different results. Based on experimental data as obtained for the
development of one of our formulations having a rather broad PSD, the capabilities of laser
diffraction (LD) and centrifugal sedimentation (CS) are demonstrated for the size
distribution characterization of submicron suspensions. In addition to this, both qualitative
and quantitative environmental scanning electron microscopy (ESEM) data are shown that
demonstrate the capabilities of this rather new approach in the evaluation of both the
morphology and the PSD of the product. Though photon correlation spectroscopy (PCS)
has shown to have limited capabilities in the PSD characterization of submicron
suspensions, with PCS related technologies the stability of the product could be assessed
by measuring the zeta potential of the drug particles. Finally, the interpretation of the PSD
data in function of the dissolution behavior of the product is illustrated by means of
correlation of the in-vitro release and PSD data. Below ca. 100 nm things get much more
complicated since in this area LD and CS have limited capabilities. The lack of reliable and
robust PSD technologies for the analysis of nano suspensions (i.e. < 100 nm) stresses the
need for other techniques in the accurate PSD characterization of these products. For this
reason, the latest developments on this area are discussed in order to help the applicant in
the selection of the right preferred analytical technologies.
F1 – Contributed Paper
45
AFM CAPABILITIES IN CHARACTERIZATION OF PARTICULATE
MATTER: FROM ANGSTROMS TO MICRONS
Paul West, Natasha Starostina, PacificNanotechnology, Inc., 17984 Sky Park
Circle, Suite J, Irvine, CA 92614, USA; nstarostina@pacificnanotech.com
Scanning Probe Microscopy has been successfully employed as surface characterization
technique for more than 20 years. Atomic Force Microscopy is the most widely used subset
of SPM, which can be used in ambient conditions with minimum sample preparation. AFM
is capable to deliver unique three-dimensional topography information from angstrom
level to micron scale with unprecedented resolution. AFM is well suited for individual
particle characterization. Standard set of measured parameters include: volume, height,
size, shape, aspect ratio and particle surface morphology. With single-particle technique,
physical parameters for each particle in a set can be recorded and the data set can be
processed to generate a statistical distribution
( i.e. ensemble-like information) for
entire set of particles. Speeding up the process of obtaining data is critical for many reasons
and definitely make AFM more attractive for individual particle imaging. In general AFM
individual particle characterizations is both cost and time effective compare to electron
microscopy. The resolution of AFM is greater or comparable to SEM/TEM. The main
advantage of AFM for particle characterization is unambiguous morphology determination
along with direct measurements of height, volume and 3D display.
61
Oral Abstracts
F1 – Contributed Paper
FEMTOSECOND PULSE VACUUM-ULTRAVIOLET-FREE ELECTRON
LASER DIFFRACTION SCATTERING OF POLYSTYRENE
NANOPARTICLES
Michael Bogan, Anton Barty, Stefano Marchesini, Henry Benner, Bruce
Woods, Matthias Frank, Stefan Hau-Riege, Henry Chapman, Lawrence
Livermore National Laboratory, 7000 East Ave, Livermore, CA, 94568, USA;
Sebastien Boutet and Janos Hadju , Uppsala University, Uppsala, Uppsala
Biomedicinska Centrum BMC, Husarg. 3, Box 596, 751 24 Uppsala, Sweden;
bogan2@llnl.gov
46
A free electron laser for wavelengths down to 6 nm in the vacuum-ultraviolet and soft
X-ray regime (VUV-FEL) is under construction at the TESLA Test Facility at DESY. It is
operated in the self-amplified spontaneous emission mode and delivers sub-picosecond
radiation pulses, with gigawatt peak powers. User experiments using this unique radiation
started in August 2005 and we performed some of the first experiments in
January/February 2006 using a wavelength of 32 nm. At this wavelength, the FEL pulse
intensities from vary typically from a few µJ up to more than 100 µJ have been obtained
with pulse lengths between 20 and 50 fs. Here, I will present femtosecond pulse diffraction
scattering data from experiments using 32 nm radiation with a target of size-monodisperse
nanoparticles. Polystyrene particles of sizes ranging from 65-145 nm were prepared for
analysis by aerosolizing them via charge-reduced electrospray, size-selecting them through
a differential mobility analyzer, and capturing them onto 20 nm thick silicon nitride
windows microfabricated in silicon wafers. Scanning electron microscopy was used to
calculate the resulting number densities on the windows (<1 to ~10 particles/μm2).
Correlation with particle number density in the aerosol, as sampled using a condensation
particle counter, enabled estimation of the number density on the window in real-time. I
will also discuss recent data collected at the Lawrence Berkeley National Lab Advanced
Light Source using 1.65 nm radiation that validated size-monodispersities of <3.5% (for
~100nm particles) after differential mobility filtering.
This work was performed under the auspices of the U.S. Department of Energy by
University of California, Lawrence Livermore National Laboratory (LLNL) under contract
No. W-7405-ENG-48 and supported by LLNL through laboratory directed research and
development grants no. 02-ERD-047 and 05-SI-003.
F1 – Invited Paper
UNDERSTANDING THE EFFLORESCENCE OF SUPERSATURATED
AEROSOLS USING FLUORESCENCE SPECTROSCOPY
Man Yee Choi and Chak K. Chan, Department of Chemical Engineering,
Hong Kong University of Science and Technology, Clear Water Bay, Hong
Kong; keckchan@ust.hk
47
The knowledge of the state of water molecules, particularly the amounts of solvated water
and free water in aqueous droplets, is valuable in understanding the hydration properties
62
Oral Abstracts
and crystallization properties of supersaturated solutions or suspended droplets. A novel
technique combining the use of an electrodynamic balance (EDB) and a fluorescence dye,
8-hydroxyl-1,3,6-pyrenetrisulfonate (pyranine), was used to study the state of the water
molecules in single levitated aqueous droplets from subsaturation to supersaturation
concentrations. The steady state fluorescence spectra of NaCl, (NH4)2SO4, Na2SO4,
MgSO4, Mg(NO3)2 and mixed NaCl and Na2SO4 (in 1:1 mole ratio) solutions doped with
100 ppm pyranine were measured. The fluorescence emission of pyranine is sensitive to
the proton transfer capacity of its microenvironment. When excited by radiation at around
345nm, pyranine fluoresces and the spectrum consists of two peaks, one at about 440nm
and the other at about 510nm, which correspond to the presence of solvated and free water,
respectively. The fluorescence peak intensity ratios of the 440nm peak to the 510nm peak
and the hygroscopic measurements were used to calculate the amounts of solvated and free
water in the droplets as a function of relative humidity (Choi et al., 2004). We found that
the equality of the amounts of solvated and free water is a necessary but not sufficient
condition for efflorescence. For efflorescing compounds such as NaCl, Na2SO4,
(NH4)2SO4, and a mixture of NaCl and Na2SO4, the amount of free water decreases, while
that of solvated water is roughly constant in bulk measurements and decreases less
dramatically than that of free water in single-particle measurements as the relative
humidity (RH) decreases. Efflorescence of the supersaturated droplets of these solutions
occurs when the amounts of free and solvated water are equal (Choi and Chan, 2005). This
study demonstrates that fluorescence spectroscopy is a unique tool in understanding the
hydration properties, the efflorescence and the structural heterogeneity of aqueous
droplets.
F1 – Contributed Paper
THREE DIMENSIONAL CHARACTERIZATION OF
PHARMACEUTICAL POWDERS BY SCANNING WHITE LIGHT
INTERFERENCE MICROSCOPY
Tim B. Vander Wood, Rachel Rose and Mary A. Miller; MVA Scientific
Consultants, 3300 Breckinridge Blvd. #400, Duluth, GA 30096;
tvanderwood@mvainc.com
48
Particle dissolution properties depend critically on the three dimensional characteristics of
the particle, specifically on the surface area to volume ratio. Traditional methods of
characterizing pharmaceutical particles and powders in three dimensions typically rely on
estimates derived from measurements made in only one dimension (e.g. light scattering
estimates of particle diameter) or, less frequently, in two dimensions (e.g. particle feret
diameters measured from micrographs of the particles in question). Rarely, three
dimensional measurements are made using stereographic properties of pairs of two
dimensional micrographs or using images of particles tilted through a known angle. These
methods are particularly suited to regular particles with a square prism habit, and are labor
intensive. We present here a method of directly characterizing particles in powder samples
using scanning white light interference microscopy. This method combines data taken
from the two dimensional (x,y) projection of each particle (as in a typical micrograph) with
direct measurement of the height (z) of each particle at every pixel encompased by the
63
Oral Abstracts
projection of each particle. This x,y,z data array is then used to directly calculate the
volume and surface area of each particle. Alternatively, the data may be used to infer an
“ideal” particle shape, and volume and surface area calculations performed for the ideal
shape. We have established the reliability of this technique for x,y dimensions of greater
than or equal to approximately 3 µm and z of greater than or equal to approximately 100
nm. We are working to extend this concept to submicrometer particles utilizing atomic
force microscopy.
F1 – Contributed Paper
POTENTIAL OF MICROCAPSULES MADE FROM PLANT POLLEN FOR
APPLICATION IN CHROMATOGRAPHY
Holger Woehlecke, Kristina Lerche, Dietmar Lerche, Dr. Lerche KG,
Rudower Chaussee 29, D-12489 Berlin, Germany; and Rudolf Ehwald,
Humboldt-University, Institute of Biology, Invalidenstr. 42, D-10115 Berlin,
Germany; office@lerche-biotec.com
49
The exine, outer wall of pollen cells, consists of sporopollenin, a polymer material which
has unique chemical and physical properties. We used mild purification methods to obtain
chemically almost unmodified sporopollenineous microcapsules from various pollen
species. Outstanding physical and chemical properties of these microcapsules encourage
their application in separation technology. They have a suitable size for chromatography
and a narrow and uniform size distribution. They are resistant to heat, organic solvents,
strong acids and alkaline solutions and they show excellent hydraulic and mechanic
properties. Using microcapsules in chromatography one has to consider the large free
liquid phase, which is enclosed by the capsule wall within the capsules. This liquid acts as
stationary phase and has to be accessible for molecules to be separated. As we have found a
highly permeable exine structure in the pine pollen air bladders, which represent capable
microcapsules, the enclosed stationary liquid phase can be used as partition space for
permeable molecules. Because of the high permeability of this special microcapsule walls
extremely large unpermeable hydrocolloids or even microparticles can be isolated from
other polymers of rather large size, e.g. most proteins. The diffusional exchange of this
large permeable polymers with the enclosed stationary eluent is very fast and not
membrane controlled. This allows for an efficient separation by size exclusion
chromatography. We present exemplary and practical applications in that field including
rapid and fast separation of giant polymer molecules as genomic DNA or
high-molecular-weight fractions of dextran, polyethylene glycol and hyaluronic acid from
permeable proteins and other polymer molecules with a Stokes' radius of up to 50 nm on
short columns (3-4 cm).
A2 – Invited Paper
NOVEL METHODS OF PRODUCING NANO- AND MICROSIZED
PARTICLES COMPOSED OF NATURAL POLYELECTROLYTES
Satoshi Iwamoto, Gifu University, Faculty of Applied Biological Sciences,
1-1,Yanagido, Gifu 501-1193, Japan; isatoshi@cc.gifu-u.ac.jp
50
64
Oral Abstracts
Two kinds of natural polyelectrolyte complexes such as chitosan and carboxymethyl
cellulose, or gelatin and acacia were used in order to prepare nano- and microsized
particles. Two types of nanoparticles with an average diameter of around 200 nm were
formed only by mixing hydrolysates of chitosan and carboxymethyl cellulose.
Nanoparticle A was produced from chitosanase hydrolysate of chitosan and cellulase
hydrolysate of carboxymethyl cellulose, and nanoparticle B was produced from lysozyme
hydrolysate of chitosan and the carboxymethyl cellulose hydrolysate. Negatively charged
compounds with high molecular weights were maintained in the particles even at the
higher pH levels than the pKa of the amino groups of chitosan. Entrapped compounds
were gradually released from nanoparticle A by lysozyme treatment. In contrast, there was
no release from nanoparticle B. These results indicate that nanoparticle A can be applied to
controlled-release drug delivery systems, and that nanoparticle B is stably retained in the
body without releasing the entrapped compounds. Another kind of complex composed of
gelatin/acacia coacervate was used to create monodisperse microparticles. In order to
product monodisperse microparticles, emulsion droplets with a narrow size distribution
were required, so microchannel (MC) emulsification, a novel method for preparing
monodisperse O/W and W/O emulsions, was applied. Generally, surfactants are necessary
for MC emulsification, but they can also inhibit the coacervation process. In this study,
surfactant-free systems were examined. The results demonstrated the potential use of
gelatin for MC emulsification. Moreover, low bloom gelatin was found to be suitable for
obtaining monodisperse emulsions. Finally, surfactant-free monodisperse droplets
prepared by MC emulsification were microencapsulated with gelatin/acacia complex
coacervate. The microsized particles produced by this technique were observed with a
confocal laser scanning microscope. Average diameters of the inner cores and outer shells
were 37.8 and 51.5μm; their relative standard deviations were 4.9 and 8.4%.
A2 – Invited Paper
PEPTIDE AND POLYMER ASSEMBLY-CONTROLLED
NANOPARTICLE FORMATION
Andreas Taubert and Wolfgang Meier, Department of Chemistry, University
of Basel, Klingelbergstr. 80, CH-4056 Basel, Switzerland;
andreas.taubert@unibas.ch; wolfgang.meier@unibas.ch
51
Many organisms are able to crystallize inorganic minerals like calcium phosphate in their
cells at room temperature and ambient pressure in aqueous media. Birds, bacteria, fish,
humans and many others not only crystallize calcium phosphate but also iron oxide and
many other minerals. These biogenic hybrid materials have advantageous properties like
high abrasion resistance or high mechanical strength. These properties often arise from a
sophisticated interplay between inorganic and organic components, which is fine-tuned by
a given organism to meet a specific requirement. One of the main questions in current
materials science is how one can in the laboratory generate materials with properties
similar to natural materials. Ideally one is able to generate a “toolbox” with which one is
able to change or adapt materials properties by design rather than by accident. We will
present an approach towards new calcium phosphate (CaP)/organic hybrid materials, that
65
Oral Abstracts
shows great promise of becoming such a toolbox. Specifically, we use synthetic
water-soluble polymers, which, in aqueous solution self-assemble into various structures
such as micelles, vesicles, polymer tubes, or lyotropic mesophases. These self-assembled
entities strongly affect the growth of CaP from aqueous solution. They can also be
modified with either short peptides or proteins to modify the CaP growth.
A2 – Contributed Paper
DEVELOPMENT OF NANOENGINEERED PLATELETS
Kent Coulter, John Cernosek, and Jim Arps, Mechanical & Materials
Engineering Division, Southwest Research Institute, 6220 Culebra Rd, San
Antonio TX, 78238-5166, USA; kent.coulter@swri.org
52
Iron nanoparticles that are superparamagnetic are being utilized in magnetic resonance
contrast enhancement, cell and DNA separation, drug delivery, and gene cloning but while
these spherical nanoparticles exhibit unique properties, the material handling, utilization in
application, and potential health and environmental issues have lead to the examination of
engineered platelet technologies that can be macroscopically manipulated and maintain the
unique nanoparticle functionality. Multilayer structures composed of alternating layers of
Fe and non-magnetic layers exhibit a range of novel magnetic properties that can be
manipulated by varying the layer thickness, topography of the interfaces and the layer
crystalline structure. Vacuum deposition of a thin film onto a substrate and the subsequent
comminuting of the film into a flake/ platelet results in unique attributes of layer thickness
control, multilayer construction, and planar geometry that are advantageous for multilayer
magnetic platelets used in biomedical applications. The development of a multilayer
iron/alumina platelet that is capped with a layer of gold provides the opportunity to take
advantage of the enhanced magnetic properties of these multilayer platelets in a
biocompatible structure. Characterization of the layered structures and resulting particles
using optical microscopy, XRD, SEM, and magnetic techniques provides information on
the platelet size and shape, particle size distribution, surface chemistry and magnetic
response. The design considerations, fabrication process, and film and platelet properties
will be discussed.
A2 – Invited Paper
GAS-PHASE SYNTHESIS AND COATING OF MULTIFUNCTIONAL
NANO- AND MICROPARTICLES FOR DRUG DELIVERY
Esko I. Kauppinen, Janne Raula, David P. Brown, Anna Lähde,
NanoMaterials Group, Center for New Materials and Laboratory of Physics,
Helsinki University of Technology, P.O. Box 1000, FIN-02044 VTT, Finland,
Hua Jiang, Juha A. Kurkela, VTT, P.O. Box 1000, FIN-02044 VTT, Finland;
esko.kauppinen@vtt.fi
53
Good flowability of pharmaceutical powders is an important feature for the handling,
processing and dispersion of dry powders. To improve flowability, the optimization of the
powder characteristics such as surface morphology and hardness is needed. It is known that
66
Oral Abstracts
a rough and hard surface minimizes the area between contacting objects and accordingly
the forces between particles, and thereby, improves detachment and flowability. This work
presents a novel aerosol flow reactor i.e. gas-phase method for in-situ synthesis and
surface-modificiation of nano- and microparticles by a volatile peptide i.e. L-leucine. In
the method, the starting solution containing drug molecules and L-leucine are atomized
and fed into a heated laminar flow reactor with the aid of carrier gas. Particles dry up
followed by evaporation of leucine. Coating on the surface of drug particles is formed by
physical deposition of L-leucine vapor. The thickness and the morphology of L-leucine
layer on the spherical salbutamol sulphate and sodium chloride core particles is controlled
by saturation conditions and residence time of aerosols in the reactor. Downstream of the
reactor, particle size distributions were determined with aerosol size spectrometers and
particle morphology was characterized with SEM and TEM. During condensation,
L-leucine formed small crystallites (nanoflakes) on the surfaces of drug particles with their
length being determined mainly by the concentration of L-leucine vapor. These nanoflakes
increased the distance and reduced the area of contact between particles. The coated
micropowders showed excellent flowability as well as dispersibility when tested with a
novel deagglomeration apparatus. The coated powders could be fed at stable rate without
the use of the lactose carrier. Coated salbutamol sulphate micropowders were fed to study
their dispersion with and without lactose carrier particles. Dispersion improved with
increased dispersion air flow rate and the degree of L-leucine coating.
A2 – Invited Paper
DNA CONDENSATION MECHANISM REVEALED UNDER
FLUORESCENCE VIDEO-MICROSCOPE
Yuichi Yamasaki, University of Tokyo, School of Eng., Dept. of Material
Eng., 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan;
yamasaki@bmw.t.u-tokyo.ac.jp
54
DNA condensation has been treated as a key phenomenon to clarify DNA packaging into a
viral capsid head or a cell nucleus, and recently attracted much attention in relation to the
non-viral gene therapy. In addition, this phenomenon is closely related to the traditional
problem of polymer physics, i.e., coil-globule transition. It has so far been believed that
DNA conformation tends to gradually shrink to a condensed state via q-state. Recently,
however, a fluorescence microscopic observation has clarified that a single DNA chain
changes its conformation from the elongated to the compact collapsed state in a discrete
manner. During the transition region, both elongated and collapse DNA chains coexist
without the presence of an intermediate conformation corresponding to the q-state,
indicating the bimodality of DNA conformation. The conformational change of DNA
seems to be related to the electrostatic property of DNA complexed with condensing
agents. Thus, the free solution DNA electrophoresis under the fluorescence microscope
was performed to obtain the relationship between DNA conformation and its residual
charges at the coexistence region of the DNA condensation transition. To evaluate both
DNA conformation and its residual charges simultaneously, an electrophoretic chamber
attachable to a microscope stage was designed. When the DC electric field (6 V/cm) was
applied, the collapsed DNA behaves as a Brownian particle, while the elongated DNA
67
Oral Abstracts
migrated toward an anode electrode with a constant mobility 1.8×10-8 m2V-1s-1. This result
indicates that the collapsed DNA was completely neutralized, while the elongated chains
still had the residual charges. At the coexistence region of the DNA collapse transition,
bimodalities not only in DNA conformation but also in its residual charges are
demonstrated using direct observation of free solution DNA electrophoresis. It is
suggested that the DNA conformational change closely correlates with the change in its
residual charges.
A2 – Contributed Paper
NOVEL NANOPARTICLE TECHNOLOGIES FOR THE
COST-EFFECTIVE, TARGETED, NON-SYSTEMIC DELIVERY OF
THERAPEUTIC AGENTS
Andrew Loxley, Christy Law, David Fairhurst, Particle Sciences Inc., 3894
Courtney St. Suite 180, Bethlehem, Pennsylvania, 18017, USA;
aloxley@particlesciences.com
55
Nanoparticles are used to carry therapeutic agents, either attached to their surfaces, or
encapsulated within the particle matrix. Early work with nanoparticle carriers focused on
injectable formulations for systemic delivery of therapeutics. We describe here a novel
technique for preparing nanoparticles for non-systemic (topically administered) targeted
delivery of therapeutic agents. Nanoparticles were prepared from a
melt-emulsification-chill process and surface-engineered to enable targeting of the
particles to specific biological surfaces including hair follicles, buccal- and vaginalmucosal surfaces and the cell surfaces of pathogens. Particles were prepared with varying
surface charge (sign and density) enabling electrostatic attachment to oppositely charged
biological surfaces, and are amenable to coating with, for example, ligands for specific cell
surface receptors. The production process uses low-cost, readily available,
biocompatible/biodegradeable materials, and low-cost processing. In this respect the
technology is ideally suited to developing world applications. A first step in the design of a
targeted therapy often involves the characterization of the targeted surface, and a novel
approach to characterizing the properties of host- or pathogen- cell surfaces,
"electrophoretic fingerprinting" is introduced that provides useful information for use in
the rational design of targeted delivery vectors, as demonstrated by the mapping of surface
properties of human T-cells.
A2 – Invited Paper
SILK MICROSPHERES PREPARED BY SPRAY-DRYING OF AN
AQUEOUS SYSTEM
Tomoaki Hino, The College of Pharmacy, Kinjo Gakuin University, 2-1723
Ohmori, Moriyama, Nagoya 463-8521, Japan; t-hino@kinjo-u.ac.jp
56
Scoured silk fiber was dissolved in an aqueous solution of calcium chloride mixed with
ethanol. After dialysis against purified water, theophylline as a model drug was added in
the solution. Silk microspheres were obtained by spray-drying. The resultant silk
68
Oral Abstracts
microsphere was round but somewhat wrinkled, and its diameter was about 5 μm. In this
way, we developed a new drug carrier without using poisonous organic solvents nor
glutaraldehyde. Silk microspheres prepared by spray-drying were exposed to humid
atmosphere (89 % relative humidity, RH). Change in the secondary structure of silk fibroin
during preparation of silk microspheres and exposure to high humidity was studied. Silk
fibroin and theophylline were found to be amorphous in the microsphere by means of
powder X-ray diffractometry. Fibroin formed β-sheet conformation in the scoured silk
fiber while it is composed of irregular structure in the microsphere according to FT-IR and
Raman spectra. Fibroin recrystallized and its secondary structure changed to β-sheet
conformation by exposing the microspheres to an atmosphere of 89 % RH.
A2 – Contributed Paper
SYNTHESIS AND APPLICATIONS OF ARRAYS OF SILICA
NANOTUBES
Igor Sokolov, Yaroslav Kievsky, Dept. of Physics and Dept. of Chemistry,
Clarkson University, Potsdam, NY 13699, USA; isokolov@clarkson.edu
57
The problem of how to “package” nanodots, carbon nanotubes, fullerenes, and other
popular nano objects into larger scale devices is one of the most important problems of
modern nanotechnology. The self-assembly of nano objects into larger functional shapes,
devices is a very attractive way of addressing this problem because of its intrinsic
simplicity and low-cost. An ultimate example of such hierarchical self-assembly exists
already in the world of biological objects. While rational design of bio objects is definitely
not a task of nowadays, an example of such hierarchical self-assembly is already
well-known. It is the coassembly of organic liquid crystals with inorganic precursor of
some metal oxides, in particular, silica. In some specific conditions such synthesis can
result in assembly of complex shapes, which resemble the shapes typically found in the
biological world. From a structural point of view, these shapes are the arrays of silica
nanotubes (ASNT). These materials are in a prime position to be used in a broad variety of
applications. The major obstacle here is a broad polydispersity of the synthesized
arrays-shapes. Here we demonstrate that this problem can be solved for at least one specific
synthesis of ASNT with high uniformity of shapes for the case of fibers, hexagonal
cylindrical bundles of straight silica nanotubes. Each such fiber contains about quarter of
million of parallel silica nanotubes, 3nm each. This is the first indication that hierarchical
self-assembly can be used for controllable “mass-manufacturing” of larger nanostructured
objects. This will contribute toward a new way of thinking about templated synthesis of
materials over length scales of tens of microns that is typically outside of the range of solid
state chemistry. Immediate applications of ASNT are drug delivery, new self-healing
materials, assembly of templates for dye microlasers, photonic microsensors, photonic
chips, etc. We will demostrate prrelimiary data for several such applications.
A2 – Contributed Paper
USE OF FLAGELLIN AND MANNOSAMINE NANOPARTICLES AS
BIOADHESIVE CARRIERS FOR MUCOSAL VACCINATION
58
69
Oral Abstracts
Carlos Gamazo1 , H.H. Salman2, J.M. Irache2 , Immunoadjuvant Unit,
Departments of Microbiology1 and Pharmaceutical Technology2, University of
Navarra, Pamplona, Spain; cgamazo@unav.es
Oral immunization using polymeric vectors including nanoparticles has been considered as
a suitable oral antigen delivery system. However, conventional nanoparticles are
considered as non-specific bioadhesive carriers, since they did not display the capacity to
target or interact specifically with specific regions within the gut, including Peyer’s
patches. The result is their rapid eliminated due to the continuous mucus turnover and
intestinal movements gastrointestinal tract. In order to overcome this drawback has been
proposed the design of new carriers with specific distribution profiles within the gut
mediated by the use of ligands able to bind to specific receptors. For this purpose, we have
designed and evaluated a polymeric vector resulting from the association between
Gantrez® AN [poly (methyl ethyl ether-co-maleic anhydride)] nanoparticles and
mannosamine or flagellin (from Salmonella Enteritidis) in order to obtain bioadhesive
nanoparticles able to interact specifically with the mucosa of the gastrointestinal tract. The
gut distribution profile of mannosylated nanoparticles or flagellin nanoparticles indicated a
strong bioadhesive capacity and an important ileum tropism. Moreover, fluorescence
microscopy demonstrated a strong uptake of these carriers by Peyer’s patches.
Immunization studies were performed in BALB/c mice using ovalbumin (OVA) as antigen
model to be loaded in nanoparticle formulations. A single dose of OVA (20 µg for S.C.
route or 100 µg for oral route) were administered in the free form or loaded in modified
(flagellin or mannosamine) nanoparticles. The use of the linkers increased the systemic
specific antibody response (IgG1 and IgG2a) and the intestinal secretory IgA levels
compared to unmodified nanoparticles. In conclusion, we propose that mannosylated
nanoparticles of flagellin nanopartciles as promising non-live vectors for oral delivery
strategies.
G1 – Keynote Paper
STRUCTURE-FUNCTION RELATIONSHIPS OF NANOMATERIALS
AND THEIR TOXICITY - A GENERAL INTRODUCTION TO
NANOMATERIALS AND THEIR USES IN MEDICINE
Vicki Colvin, Center for Biological and Environmental Nanotechnology, Rice
University, 6100 Main Street, MS-63, Houston, Texas 77005, USA;
colvon@rice.edu
59
Traditionally, nanotechnology has been motivated by the growing importance of very
small (d < 50nm) medicinal, computational, and optical elements in diverse technologies.
Our effort has considered broadly how these features can be leveraged in environmental
technologies. We consider how the nano/bio interface manifests itself in cell culture
systems, thus giving an indication of the toxic effects of a nanoparticle. For example, we
consider the environmental chemistry and biological interactions of a model nanostructure,
carbon-60 (C60). Though a hydrophobic substance, fullerenes form stable, sub-micron,
colloidal clusters which can persist in water for long times under a variety of conditions.
This behavior makes fullerenes more accessible to biological systems and permits them to
70
Oral Abstracts
have a marked effect on bacteria and cells in culture. However, it is the structure of the C60
aggregate that determines its function in a biological entity. Specifically, the more
water-soluble derivatives are covalently attached to the surface of the C60 cage, the less
toxic it becomes. The ability to change the structure of the nanomaterial, thus tune its
toxicity, will indeed greatly advance the current research in drug delivery, diagnosis, and
patient recovery.
G1 – Invited Paper
NANOPARTICLE-INDUCED BIOLOGICAL RESPONSES: EFFECT OF
SIZE, SHAPE AND SURFACE CHEMISTRY
Hong Yang, Xiaowei Teng, Department of Chemical Engineering, University
of Rochester, 206 Gavett Hall, Rochester, NY 14627; and Alison C. Elder,
Nancy Corson, Department of Environmental Medicine, University of
Rochester School of Medicine, 575 Elmwood Avenue, Rochester, NY 14642;
hongyang@che.rochester.edu
60
The property of nanomaterials can depend heavily on the size, shape and surface
chemistry. It is not unexpected that these structural properties are important factors which
can affect the response biological systems upon the exposure to nanomaterials. In this talk,
I will first present several methods for controlling the size and shape of colloidal metal and
metal oxide nanoparticles. Monodisperse iron oxide nanoparticles and platinum shapes
have been used as model systems for understanding the cellular responses, following the
exposure to nanometer-sized materials. Surface of these nanoparticles has been modified
and their compatibility in culture medium has been examined accordingly. The toxicity of
nanoparticles was followed in cultured lung epithelial cells (A549) based on the lactate
dehydrogenase (LDH) release or luciferase reporter activity. For platinum nanoparticles,
different shapes (particle, multipod and porous particle) have been synthesized in solution
phase (Teng, Yang, Nano Lett., 2005, 5, 885; Teng, Liang, Maksimuk, Yang, Small, 2006,
2, 249). The shape-depedent the oxidative stress and toxicity in cultured epithelial and
endothelial cells have been studied. I will present the observed difference in shape-related
biological response and discuss the possible mechanism.
G1 – Invited Paper
PHYTOTOXICITY OF SOME MANUFACTURED NANOPARTICLES
Daniel J. Watts, Otto H. York Center for Environmental Engineering and
Science, New Jersey Institute of Technology, University Heights, Newark, NJ
07102; and Ling Yang, Department of Environmental Engineering, Beijing
University of Chemical Technology, 15 North Sanhuan East Road, Beijing
100029, P.R. China; watts@njit.edu
61
The rapid development of nanotechnology and the growing application of nano-sized
substances are bringing large quantities of manufactured nanomaterials into the
environment. Epidemiological studies have suggested that fine particles with aerodynamic
diameter smaller than 2.5 μm have a relative association with various adverse health effects
71
Oral Abstracts
in humans. Studies have indicated that manufactured nanomaterials may impose harmful
effects on human health. Results suggesting harm were also observed in aquatic organisms.
Little or no investigation though has been reported on the effects of nano-sized materials in
plant systems. In this study, toxicities of manufactured nanoparticles including 13-nm
alumina from Degussa, 14-nm hydrophilic silica from Cabot, and 21-nm titania from
Degussa, are evaluated by means of a root elongation test. Six plant species, Zea mays
(corn), Avena sativa (oat), Cucumis sativus (cucumber), Glycine max (soybean), Brassica
oleracea (cabbage), and Daucus carota (carrot) were used in this study of the phytotoxicity
of nanoparticles. For comparison purposes, phytotoxicity of larger particles, including
161.2-nm hydrophilic silica (produced at NJIT), 1.0-μm alumina (Atlantic Equipment
Engineers, Inc), 667.6-nm hydrophilic silica (Anonymous Manufacturer), and 0.96-μm
titania (Atlantic Equipment Engineers, Inc), were investigated. It was found that 1) the
667-nm silica, the 0.96-μm titania, and the 1.00-μm alumina showed no toxic effects on
plant root elongation, 2) among the nanoparticles, the 13-nm alumina could retard the
seedling development, whereas the 14-nm silica increased root elongation, and no effects
were found for the 21-nm titania, 3) the 161-nm silica had an inhibitory effect. Results of
further studies on toxicity mechanisms induced by the 13-nm alumina nanoparticles
suggested that phytotoxicity of the nanoparticles seemed to be related to 1) surface
properties, not size properties of the nanoparticles, 2) oxidation reaction between the
nanoparticles and the plant organisms, and 3) the ability of nanoparticles to enter the root.
G1 – Invited Paper
COMPLEMENT-MEDIATED HYPERSENSITIVITY REACTIONS TO
NANOPARTICULATE DRUGS AND SOLVENT SYSTEMS
Janos Szebeni, US Military HIV Research Program, 1600 E Gude Drive,
Rockville, MD 20850 and Nephrology Research Center, Semmelweis
University, Hungarian Academy of Sciences, Budapest 1089 Nagyvarad ter 4,
Hungary; jszebeni@hivresearch.org
62
One of the new trends in modern pharmacotechnology is to apply nanoparticulate drug
carriers, vehicles or solvents in order to increase the therapeutic index of existing drugs.
Beside all demonstrated clinical benefits or promising preclinical data, this approach
unavoidably entails at least one problem, the induction of acute hypersensitivity (HSR, or
anaphylactoid, or idiosyncratic) reactions. The phenomenon is due to the physical and/or
chemical similarity of drug particles to many natural pathogens (viruses, bacteria and other
microbes) against which the immune system is normally sensitized. However, this state of
sensitization differs from that mediated by IgE, as it arises as a consequence of activation
of the complement (C) system. Hence the new term, “C activation-related pseudoallergy”
(CARPA). Drugs and agents causing CARPA include radiocontrast media (RCM),
liposomal drugs (Doxil, Ambisome and DaunoXome) and micellar solvents containing
amphiphilic lipids (e.g., Cremophor EL, the vehicle of Taxol). These agents activate C
through both the classical and the alternative pathways, giving rise to C3a and C5a
anaphylatoxins that trigger mast cells and basophils for secretory response that underlies
HSRs. Recent studies suggest that it might be possible to screen candidate drugs or drug
carriers for C activation and subsequent CARPA, using C split product (SC5b-9 ELISA)
72
Oral Abstracts
assays and the porcine “cardiovascular distress” model, wherein quantification of the
hemodynamic, cardiopulmonary and ECG changes allows for the assessment of the
reactogenic potential of particulate drugs and agents. In conclusion, our studies suggest
that the CARPA concept and the in vitro and in vivo assays that we use may help in the
prediction, prevention and treatment of the acute immune toxicity of numerous
state-of-the-art drugs.
G1 – Contributed Paper
AQUEOUS DISPERSIONS OF CARBON NANOTUBES FOR
BIOLOGICAL TESTING AND APPLICATIONS
Natalia Varaksa, Tammy Oreskovic, and Paul Rice, National Institute of
Standards and Technology; Materials Reliability Division, Boulder, Colorado
80305, USA; varaksa@boulder.nist.gov
63
Due to their exceptional structural, mechanical, and electrical properties, as well as their
chemical inertness, carbon nanotubes (CNTs) are often envisioned as candidates for
biological and medical materials and devices. Some of the possible applications include
drug and vaccine delivery, tissue engineering (neural and orthopedic tissue implants,
vascular grafts), biosensors, and biocomposites. However, the high hydrophobicity of
CNTs and their tendency to remain in bundles make them difficult to form homogeneous
and stable dispersions in liquids, especially in aqueous solutions. Aqueous solutions and
cell culture media are of particular interest in biological and medical studies, which
prompted our investigation into aqueous dispersion of CNTs. One way to make CNTs
more hydrophilic and thus to facilitates their dispersibility in aqueous solutions is to
immobilize certain surfactants or polymers on CNT walls and/or edges. In addition a
critical consideration, for biological applications, is that these surfactants and polymers
should be nontoxic and biocompatible. In our work, we focused on the selection and testing
of various surfactants considering their dispersive power of multi-walled carbon nanotubes
(MWCNTs), and also their biocompatibility with living cells. These suspensions were
evaluated by optical (due to the size of MWCNTs) and scanning electron microscopies.
Their stability was evaluated by visual inspection over the course of several days. For
biocompatibility tests the response of vascular smooth muscle cells (VSMCs) and
fibroblasts to MWCNTs was studied. The viability of cells cultured in the presence of
MWCNT suspensions was evaluated using optical and electron microscopies as well as
Alamar Blue (a cell proliferation assay). Results of the Alamar Blue indicated that liquid
suspensions of MWCNTs did not present cytotoxic activity against VSMCs and
fibroblasts. These results permit us to claim that MWCNTs coated with nontoxic
surfactants are biocompatible with VSMCs and fibroblasts, and can be considered as
candidates for biomedical applications.
G1 – Contributed Paper
TOXICOLOGICAL IMPACT STUDIES BASED ON ESCHERICHIA COLI
BACTERIA IN AN ULTRAFINE ZnO NANOPARTICLES COLLOIDAL
MEDIUM
64
73
Oral Abstracts
Roberta Brayner and Fernand Fiévet, Interfaces, Traitements, Organisation et
Dynamique des Systèmes (ITODYS), UMR-CNRS 7086, Université Paris
7-Denis Diderot, case 7090, 2 place Jussieu, 75251 Paris Cedex 05, France;
Roselyne Ferrari-Iliou and Marc F. Benedetti, Laboratoire de Géochimie des
Eaux, UMR-CNRS 7047, Université Paris 7 & IPGP - 2 place Jussieu, 75251
Paris Cedex 05, France ; brayner@ccr.jussieu.fr
We report here preliminary studies of toxicological impact of ZnO nanoparticles on
Escherichia coli bacteria. ZnO nanoparticles were synthesized in diethylene glycol (DEG)
medium by forced hydrolysis of ionic Zn2+ salts. Particle size and shape were controlled by
addition of small and macromolecules such as tri-n-octylphosphine oxide (TOPO), sodium
dodecyl sulfate (SDS), polyoxyethylene stearyl ether (Brij-76) and bovine serum albumin
(BSA). Transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses
were used to characterize particle structure, size and morphology. Bactericidal tests were
performed in Luria-Bertani (LB) medium on solid agar plates and in liquid systems with
different concentrations of small and macromolecules and also with ZnO nanoparticles.
TEM analyses of bacteria thin sections were used to study biocidal action of ZnO
materials. The results confirmed that E. coli cells after contact with DEG and ZnO were
damaged showing a Gram-negative triple membrane disorganization. This behavior causes
the increase of membrane permeability leading to accumulation of ZnO nanoparticles in
the bacterial membrane and also cellular internalization of these nanoparticles.
H1 – Keynote Paper
PHOTODYNAMIC THERAPY IN THE CHORIOALLANTOIC
MEMBRANE MODEL: COMBINATION THERAPY USING ASPIRIN
ENHANCES PHOTODYNAMIC SELECTIVE DRUG DELIVERY AND
INFLUENCE OF THE SIZE OF TCPP-LOADED NANOPARTICLES ON
PHOTOTOXICITY
Hubert van den Bergh, Elodie Debefve, Bernadette Pegaz, Jean-Pierre
Ballini; Swiss Federale Institute of Technology (EPFL), LPAS- Station 6,
CH-1015 Lausanne, Switzerland; hubert.vandenbergh@epfl.ch
65
Vascular hyperproliferation characterises several diseases, including cancer and
age-related macular degeneration (AMD). One therapeutic approach that is based in part
on the closure of the vascular networks associated with these diseases is photodynamic
therapy (PDT). The final result is vascular collapse and blood flow stasis leading to the
occlusion of the pathological irradiated neovascularization. Two studies in the
chorioallantoic membrane model (CAM), intending to improve the outcome of it are
described here:
1) Combination therapy using aspirin enhances photodynamic selective drug delivery.
The aim of the present study was to develop a novel combination therapy approach, in
which we take advantage of the transient enhanced vascular permeability in PDT using
aspirin, to selectively release at the location where PDT is inducing the vascular response,
chemotherapeutic agents in the case of treatment of a malignant tumor or antiangiogenic
factors to prevent growth/regrowth of the neovasculature in the case of AMD. The synergy
74
Oral Abstracts
of the highly localised chemotherapy with local closure of the blood vessels that supply the
tumour then leads to new and more effective treatment possibilities for various neoplasms.
2) Influence of the size of TCPP-loaded nanoparticles on phototoxicity.
To be useful as a therapeutic regimen, some selectivity between the target tissue and the
neighbouring healthy structures must be achieved by choosing a suitable delivery system
for the photosensitizer (PS). Hence, the main goal of the present study was to develop a
polymeric carrier system such as nanoparticles (NP) for PS intended to be intravenously
administrated, capable of increasing the therapeutic index of the PS. To assess the effect of
the size of NP in terms of photothrombic activity, four sizes of TCPP-loaded NP
(121-343nm) were synthetized using the salting-out technique with biodegradable
polymer. The PDT-induced vacular damage proportionaly decreases with the size of the
TCPP-loaded NP.
H1 – Invited Paper
NANOPARTICLE SELF-LIGHTING PHOTODYNAMIC THERAPY FOR
CANCER TREATMENT
Wei Chen, Nomadics Inc., 1024 S. Innovation Way, Stillwater, OK 74074,
USA; wchen@nomadics.com
66
The purpose of this new design is to find a more efficient treatment for cancer while
reducing the risk of radiation damage. To reach this goal, we proposed a novel method for
cancer treatment that combines radiotherapy and photodynamic therapy (PDT). Under this
concept, scintillation or persistent luminescence nanoparticles with attached
photosensitizers, such as porphyrins, are used as a new type of agent for photodynamic
therapy. Upon exposure to ionizing radiation such as X-ray, scintillation or persistent
luminescence will emit from the nanoparticles to activate the photosensitizers; as a
consequence, singlet oxygen (1O2) is produced to augment the killing of cancer cells by
ionizing radiation. With this novel therapeutic approach, no external light is necessary to
activate the photosensitizing agent within tumors. Thus, this new modality is called
nanoparticle self-lighting photodynamic therapy.
H1 – Contributed Paper
TIME-RESOLVED SPECTROSCOPY STUDY OF THE PHOTOTHERMAL
PROPERTIES OF GOLD NANOCAGES
Min Hu, Jingyi Chen, Xingde Li, Younan Xia Department of Chemistry and
Department of Bioengineering, Univ. of Washington, Seattle, WA 98195;
Hristina Petrova, Gregory V. Hartland, Department of Chemistry and
Biochemistry, Univ. of Notre Dame, Notre Dame, IN 46556; Manuel Marquez,
INEST Group, Research Center, Philip Morris USA Inc., Richmond, VA
23234; mhu2@u.washington.edu
67
Gold nanocages were synthesized from silver nanocube templates via a galvanic
replacement reaction. The Surface Plasmon Resonance (SPR) peak of the nanocages can
be tuned into the near-IR region, which makes them promising candidates for photothermal
75
Oral Abstracts
therapy and biological imaging applications. Gold nanocages of different sizes dispersed in
water solution have been studied by ultrafast time-resolved spectroscopy. The
experimental results show that the energy relaxation time increases as the size of the
particles increases, and the relaxation time is independent of the initial particle temperature
with different excitation powers. Modulations due to coherently excited vibrational modes
were also observed in the transient absorption traces. The period of the excited vibrational
motion is proportional to the dimensions of the particles. For a specific size of nanocage,
experiments with different excitation powers of the pump laser were performed (from 2 µJ
to 17 µJ), we found that the period of the vibrational mode increased with the laser
intensity. This was compared to experiments on spherical gold nanoparticles, which allow
us to roughly estimate the temperature of the nanocages when the electrons and the
phonons reach the equilibrium. We estimate that the 17 µJ pump energies produce a lattice
temperature of 1100 ± 100 K in the nanocages, which is near the melting point of the bulk
metal, while the particles maintain their integrity. This makes the gold nanocages
potentially useful for photothermal therapy applications.
H1 – Invited Paper
LASER IRRADIATED GOLD NANOPARTICLES: A NEW TOOL FOR
SELECTIVE MAINPULATION OF CELLS AND BIOMOLECULES
Gereon Hüttmann, Marco Bever, Institute of Biomedical Optics, University
Luebeck, Germany; Cuiping Yao, School of Life Science and Technology,
Xi’an Jiaotong University; China, Ramtin Rahmanzadeh, Johannes Gerdes,
Research Center Borstel, Germany; Florian Lewolth, Elmar Endl, Institute of
Molecular Medicine and Experimental Immunology, University. Bonn,
Germany
68
The strong absorption of gold nanoparticles in the visible spectral range allows the
localized generation of heat in a volume of only a few tens of a nanometer. Irradiation with
a pulsed lasers can easily heat up the particles above the melting temperature of gold. Due
to their small volume cooling by heat diffusion is very efficient. Therefore temperatures
above 1000°C can be confined to the surroundings of the nanoparticles with heating times
in the sub-nanosecond range. Pulsed irradiation of gold nanoparticles is therefore expected
to cause very localized chemical, thermal or mechanical modifications to cells and
biomolecules. We demonstrate the selective destruction of proteins, the permeabilization
of the cell membrane and selective killing of cells by laser-irradiated gold nanoparticles.
Conjugates made from the different enzymes with nanoparticles served as a model system
for investigating the effect of laser-irradiated nanoparticles on proteins. We were able to
show, that an inactivation of the enzymes is possible with very high spatial confinement.
Permeabilization was studied systematically in different cells lines. Antibodies against
membrane proteins were conjugated to gold nanoparticles. The conjugates than were
bound to the cell membrane and subsequently irradiated by nanosecond and picosecond
laser pulses. Transient permeabilization was observed for 10 kDa Dextran. Efficacies of
more than 60% were attained under optimal conditions with only 27% cell death. When
irradiated with higher pulse energies, cells to which the gold particles were bound, were
effectively killed. In mixed cell cultures of different lymphoma cells, the targeted cells
76
Oral Abstracts
were killed with over 95% efficacy without significantly affecting the non-targeted cells.
In combination with selectively binding antibodies, laser-irradiated gold nanoparticles
allow a precise and effective destruction of biomolecules and cells, which can be used for a
new kind nanoparticle mediated cell surgery (NPCS). Possible application are protein
knock-out, cell purging or a selective depletion of cells from cell or tissue culture.
H1 – Invited Paper
ANGIOGENIC VESSEL-TARGETED CANCER THERAPY
Naoto Oku, Tomohiro Asai, Kosuke Shimizu, Sei Yonezawa, Univ. of
Shizuoka, Dept. of Medical Biochem., Yada, Suruga-ku, Shizuoka 422-8526
Japan; oku@u-shizuoka-ken.ac.jp
69
Since angiogenic endothelial cells have growing character, these cells are expected to be
degenerated by anticancer drugs like as cancer cells. We have developed a new modality of
cancer treatment by use of DDS technology, in which anticancer drugs are effectively
delivered to the angiogenic endothelial cells of a solid tumor. Anti-neovascular therapy
(ANET) may cause indirect lethal damage of tumor cells through the damage of newly
formed blood vessels with reduced side effects. Moreover, this therapy overcomes
drug-resistance tumors. To develop liposomal DDS drugs that target angiogenic vessels,
we previously isolated peptides specific for tumor angiogenic vasculature using a
phage-displayed peptide library, and thus obtained APRPG peptide was used for liposomal
modification. APRPG-PEG-modified liposomes encapsulating adriamycin or entrapping a
hydrophobized prodrug of CNDAC, a novel anticancer drug, caused strong tumor growth
suppression through possible damaging of angiogenic endothelial cells. The accumulation
of APRPG-PEG-liposomes was quite similar to that of control PEG-liposomes. However,
intratumoral distribution of APRPG-PEG-liposomes was quite different from the control
liposomes: The former colocalized with endothelial cells, and the latter accumulated the
surrounding of the blood vessels when the intratumoral distribution of
fluorescence-labeled liposomes was examined by confocal laser scanning microscopy. By
the way, pancreatic cancer is intractable, and shows poor development of angiogenic
vessels suggesting a large number of tumor cells are controlled by a small number of vessel
cells. Therefore, we applied ANET to pancreatic cancer model prepared by orthotopical
implantation of human pancreatic tumor line cells, and observed the superior growth
suppression of the tumor by the treatment of angiogenic vessel-targeted liposomal
adriamycin. The present study provides a novel modality of cancer treatment.
H1 – Invited Paper
70
DEVELOPMENT OF TUMOR TARGETING MAGNETIC
NANOPARTICLES FOR CANCER THERAPY
Robert Ivkov1, Sally J. DeNardo2, Laird A. Miers2, Arutselvan Natarajan2,
Allan R. Foreman1, Cordula Gruettner3, Grete N. Adamson2, and Gerald L.
DeNardo2; 1Triton BioSystems, Inc., Chelmsford, MA; 2Radiodiagnosis and
Therapy, Molecular Cancer Institute, University of California, Davis,
Sacramento, CA; 3Micromod Partikelteknologie GmbH, Rostock, Germany;
77
Oral Abstracts
rivkov@tritonbiosystems.com
Magnetic nanoparticles will rapidly heat, via hysteresis losses, when activated by an
alternating magnetic field (AMF). Systemic delivery of magnetic nanoparticles
conjugated to a monoclonal antibody (MAb) offers potential for selective and minimally
invasive cancer treatment by heating the microenvironments of cells containing particles
embedded in cancer tissue. One to two MAb’s per nanoparticle were conjugated using
1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide HCl (EDC), 111In-7,10-tetraaza
cyclododecane-N, N’, N’’, N’’’-tetraacetic acid-ChL6 (111In-DOTA-ChL6) to carboxylated
polyethylene glycol (PEG-COOH) on dextran-coated iron oxide 20 nm particles. After
magnetic purification and sterile filtration, pharmacokinetics, histopathology, and
AMF/bioprobe therapy were done using 111In-ChL6 bioprobe intravenous doses
(20μg/2.2mg ChL6/ bioprobe) with 50μg ChL6 in athymic mice bearing HBT3477
xenografts. A 153 kHz AMF was applied 72 hr post injection (pi) for therapy with
amplitudes of 1,300, 1,000 or 700 Oersteds. Weights, blood counts and tumor size were
monitored and compared with control mice receiving nothing, or AMF or bioprobes alone.
111
In-ChL6 bioprobe binding in vitro to HBT3477 cells was 50 to 70% of that of
111
In-ChL6. At 48 hours, tumor, lung, kidney, and marrow uptake of the 111In-ChL6
bioprobes were not different from that observed in prior studies of 111In-ChL6. Significant
therapeutic responses from AMF/bioprobe therapy were demonstrated with up to eight
times longer mean time to quintuple tumor volume with therapy compared with no
treatment (P = 0.0013). Toxicity was only seen in the 1,300 Oe AMF cohort, with 4 of 12
immediate deaths and skin erythema. Electron micrographs showed bioprobes on the
surfaces of the HBT3477 cells of excised tumors and tumor necrosis 24 hours after
AMF/bioprobe therapy. This study shows that MAb-conjugated nanoparticles
(bioprobes), when given intravenously, escape into the extravascular space and bind to
cancer cell membrane antigen. Bioprobes can be used in concert with externally applied
AMF to deliver thermoablative cancer therapy.
H1 – Contributed Paper
METHACRYLAMIDE-OLIGOLACTATES AS BUILDING BLOCKS FOR
TARGETED BIODEGRADABLE POLYMERIC MICELLES TO DELIVER
PHOTOSENSITIZERS
Cristianne J.F. Rijcken, Jan-Willem Hofman, Femke van Zeeland, Aissa
Ramzi, Wim E. Hennink and Cornelus F. van Nostrum, Deptartment of
Pharmaceutics, Utrecht Inst. for Pharmaceutical Sci. (UIPS), Utrecht Univ.,
P.O. Box 80082, 3508TB, Utrecht, The Netherlands;
C.F.vanNostrum@pharm.uu.nl
71
A class of generally very hydrophobic drugs is the group of photosensitizers, which are
currently under investigation in photodynamic therapy (PDT) to treat cancer. Upon
irradiation with light of a specific wave length, photosensitizers generate a variety of
reactive oxygen species. The radical compounds damage various cell components and
ultimately lead to cell death. However, the hydrophobicity of many photosensitizers results
in an unfavorable biodistribution (e.g. prolonged skin toxicity) and aggregation with
78
Oral Abstracts
subsequent quenching of the excited state, lower radical production, etc. These side effects
necessitate the photosensitizers to be encapsulated in an adequate carrier system to deliver
them specifically to the tumor regions, preferably in a solubilized state. It is the aim of this
study to apply biodegradable thermosensitive polymeric micelles as a delivery vehicle for
photosensitizers and to target the carrier specifically to neck/head cancer cells.
The polymers used in this study are based on methacrylamide-oligolactates, which display
thermosensitive behavior that is transient under physiological conditions due to hydrolysis
of the lactate side chains. Amphiphilic block copolymers synthesized using a
PEG-macroinitiator, self-assemble in aqueous media into highly condensed spherical
micelles above the cloud point (CP) of the thermosensitive block. Cleavage of the lactic
acid side chains causes a gradual increase of the critical micelle temperature (CMT) and
leads to controlled destabilization and eventually dissolution of the thermosensitive
biodegradable polymeric micelles. The CP and the destabilisation time period can be
tailored by varying the methacrylamide backbone and the length of the oligolactate chain.
A degradation-controlled release of a novel, highly potent photosensitizer (a substituted
silicon phthalocyanine) was observed in vitro. The hydrophobic core of the micelle and
physiological destabilization can be exploited for a controlled delivery of drugs.
H1 – Invited Paper
PORPHYRIN-NANOPARTICLE SENSORS FOR DETECTING
CELLULAR RESPONSE(S) TO OXIDATIVE STRESS ASSOCIATED
WITH REACTIVE OXYGEN SPECIES AND PDT
Leanne B Josefsen, Ross W Boyle, Photobiology and Photomedicine Group,
Departments of Chemistry and Clinical Biosciences, The University of Hull,
Cottingham Road, Hull, East Yorkshire, HU6 7RX, UK;
l.b.josefsen@chem.hull.ac.uk
72
The sensor is based on a porphyrin and a polyacrylamide nanoparticle, which bear specific
functionalities to allow conjugation of the two components. The conjugates are designed to
allow real-time monitoring of intra-cellular signals in response to oxidative stress caused
by reactive oxygen species, such as those generated during PDT. By selectively
functionalising the porphyrin to carry an isothiocyanato group and the nanosensor free
primary amines, an isothiourea bond is formed between the porphyrin and nanosensor
conjugate. The role of the porphyrin is (i) to promote localisation to specific sub-cellular
compartments and (ii) to generate reactive oxygen species, similar to those released in
porphyrin-mediated PDT. The first of these two criteria is met by imparting a net cationic
charge on the porphyrin. Reactive oxygen species are then generated by exciting the
porphyrin at a specific wavelength. The subsequent cellular response can then be
monitored by the nanosensor. The nanosensor works by encapsulating an ion-selective
fluorophore within the sensor matrix. The fluorophore selectively interacts with specific
analytes/ions that have passed through surface pores into the sensor matrix, allowing
real-time monitoring of the cells response. Insertion of these porphyrin-loaded sensors into
cells and subsequent irradiation with light of an activating wavelength, generates reactive
oxygen species. By controlling the amount of porphyrin attached to the sensors and the
light dose absorbed by the porphyrin, the amount of reactive species generated can be
79
Oral Abstracts
varied and the cellular response to oxidative stress measured. The nanosensors desrcibed
here thus have potential for studying cell signaling events occuring in PDT between
photosensitiser activation and cell death, and also for elucidating mechanisms of
cytotoxicity associated with the intracellular generation of reactive oxygen species in
general.
D2 – Keynote Paper
QUANTUM DOTS AS IMMUNOASSAY PROBES
Roger M. Leblanc, University of Miami, Department of Chemistry, 1301
Memorial Drive, Cox Science Center, Coral Gables, FL, USA;
rml@miami.edu
73
Peptides were incorporated with organic fluorophores and luminescent quantum dots
(QDs) for molecular recognition studies as well as imaging of biological processes.
Fluorescent peptides containing the Gly-His or Gly-Gly-His Cu2+ binding motifs
selectively detected the metallic ion at the µM level in solution. Divalent copper was also
selectively detected by similar peptide lipids at the air-water interface in 2D and
Langmuir-Blodgett films. Photosensitive peptide systems and hydrogels were utilized to
prepare Cu2+ membrane probes. Surface functionalization of cadmium chalcogenides QDs
with peptides allowed detection of Cu2+ with nM detection potential. The photosensitive
hydrogels can also physically immobilize QDs for preparation of hydrogel membrane
probes. The layer-by-layer assembly technique helped to build ultra thin films of QDs and
organophosphorus hydrolase (OPH) on quartz for detection of paraoxon, a potent
neurotoxin. Paraoxon was detected at the nM levels. The results are compared to QD/OPH
systems in solution. Staining of ß-amyloid (fragments and full length) aggregation process
in solution, dry films, and at the air-water interface was monitored with QDs. Langmuir
films were further utilized to characterize and manipulate the 2D self-assembly of QDs at
the air-water interface. Self-assembled QD monolayers can be deposited onto solid
substrates utilizing the LB film deposition technique. Practical applications include
fabrication of analytical solid devices with controlled nanoparticle organization.
D2 – Invited Paper
DEVELOPMENT OF FRET-BASED QD-BIOCONJUGATE SENSORS
FOR DETECTING ENZYMATIC ACTIVITY
Hedi Mattoussi, Igor L. Medintz, Aaron R. Clapp, U.S. Naval Research
Laboratory, Washington, DC 20375; Optical Sciences Division and Center for
Bio/Molecular Science and Engineering; and Florence M. Brunel, Philip E.
Dawson, Departments of Cell Biology & Chemistry, The Scripps Research
Institute, La Jolla, CA 92037; hedimat@ccs.nrl.navy.mil
74
We have previously demonstrated the use of self-assembled QD-protein-dye bioconjugates
to design sensing assemblies based on Förster resonance energy transfer - (FRET) for
signal transduction. Solution-phase sensors specific for the detection of the nutrient
maltose and the explosive TNT were developed. The sensor design exploited a few
80
Oral Abstracts
inherent benefits of using QDs over conventional organic fluorophores for FRET,
including: 1-the ability to size-tune fluorescent emission as a function of QD core size to
better match overlap with a particular acceptor; and 2-the option of arraying multiple
acceptors around a QD to increase the overall FRET efficiency. In the present
investigation, we apply these QD-bioreceptor assemblies to detect the activity of several
proteolytic enzymes in vitro. In particular, we focus on the digestion of protein and
cleavage of peptide substrates by specific proteolytic enzymes. Assembling
QD-peptide-dye and QD-protein-dye conjugates brings the dye in close proximity to the
QD and results if efficient FFET between dots and dye, which translates in loss of QD
photoemission. Digestion of the dye-labeled protein or peptide by the target enzyme
displaces the free dye from the QD surface and reduces the FRET efficiency. Measuring
changes in the FRET efficiency allows monitoring of the specific protease activity. A
calibration curve derived from an increasing number of acceptors per donor allowed
transformation of the FRET changes into units of enzymatic activity. We applied this
sensing concept/design to detect activity of endopeptidases proteinase K or papain and
several peptidases (e.g., caspace-1 and thrombin). These peptidases are involved in
inflammation and blood coagulation, respectively. Changes in FRET efficiency were also
monitored when inhibitors were added to the peptide containing assay solutions. Analysis
of the data was carried out within the framework of the Michaelis-Menten treatment using
different mechanisms of inhibition. Practical applications for this technology will also be
discussed.
D2 - Contributed Paper
GIANT MAGNETIC QUANTUM DOTS AS INDIVIDUALLY
ADDRESSABLE HIGH SENSITIVE OPTICAL BAR CODES FOR
DIAGNOSTICS AND BIOANALYTICS
D. Müller-Schulte, MagnaMedics GmbH, Martelenberger Weg 8, D-52066
Aachen, Germany, detlef.mueller2@post.rwth-aachen.de; P.Borm,
Hogeschool Zuyd, NL-6400 Heerlen, The Netherlands
75
Spherically-shaped nano- and micro particles on the basis of silica gels were synthezised
using a newly designed inverse suspension technology. Total transparency, no
autofluorescence and varied bead sizes from 0,5 to 3000 µm are some of the unique
features of these prepared beads. In addition, the new silica bead technology for the first
time allows the simultaneous encapsulation of quantum dots, fluorescence dyes and
magnetic colloids. By encapsulating a huge number of diverse quantum dots into the silica
matrix, extremely strong luminescent micro and nano carriers (“giant quantum dots “) are
obtained covering the whole visible spectral range. The newly designed particles can be
ideally used for individually optical coding of biomolecules and cells. The application is
exemplarily demonstrated for tumor cell screening and proteomics.
D2 – Contributed Paper
SYNTHESIS OF ULTRA-STABLE BARE CDS NANOCRYSTALS WITH
STRONG LUMINESCENCE BY HYDROTHERMAL SYNTHESIS
76
81
Oral Abstracts
Yongxian Wang, Ronghui Xu, Wanbang Xu, Radiopharmaceutical centre of
Shanghai Institute of Applied Physics, Chinese Academy of Sciences,
Shanghai 201800, China; and Guangqiang Jia, Instrumental Analysis and
Research Centre of Shanghai University, Shanghai 200444,China;
yongxianw@163.com
Ultra-stable bare CdS quantum dots (QDs) with a size between 1.5 nm and 8 nm and strong
luminescence were synthesized directly by hydrothermal synthesis method. The
nanocrystals emit highly symmetric fluorescence whose full width of half-maximum
(fwhm) is as narrow as 80 nm. The bare QDs retain robust keeping in reacting mixtures for
at least 45 days. The parameters influencing stability, size and fluorescence are discussed
in detail. Having used a combination of X-ray Diffraction (XRD), Atomic Force
Microscopy (AFM), High Resolution Electron Microscopy (HRTEM),
Fluorescence/UV-VIS spectroscopy, EDS to analyze the chemical composition, size,
shape, and crystal structure etc, we found that the semiconductor quantum dots of CdS
produced via hydrothermal method were not only ultra-stable but also highly luminescent,
mainly owing to the perfect structure of QDs.
D2 – Invited Paper
COLLOIDAL SEMICONDUCTOR QUANTUM DOTS IN SELECTIVE
LABELING OF PATHOGENIC BACTERIA
Todd D. Krauss and Megan A. Hahn, University of Rochester, Department of
Chemistry, Rochester, New York, 14627-0216, Joel S. Tabb, Agave
BioSystems, Ithaca, NY 14850, krauss@chem.rochester.edu
77
Having diameters of only a few nanometers, colloidal CdSe semiconductor quantum dots
(QDs) are highly emissive, spherical, inorganic particles that exhibit size-tunable physical
properties due to the effects of quantum confinement. Typically, these materials are
synthesized with relatively inert hydrocarbon surface-groups that must first be modified if
they are to be compatible with biological systems. To that end, a variety of different
strategies have been established to make these hydrophobic surfaces of CdSe QDs
applicable for use in biology. We have demonstrated that CdSe/ZnS core/shell QDs
functionalized with streptavidin bind specifically to pathogenic Escherichia coli O157:H7
cells labeled with biotinylated antibodies. Using fluorescence microscopy of individual
bacterial cells and standard fluorimetry of bacterial cell solutions, we will present results
comparing E. coli O157:H7 cells labeled with QDs to cells similarly labeled with a
standard dye, fluorescein isothiocyanate (FITC). We will also present the results of using
flow cytometry to analyze bacterial cell mixtures, which contained pathogenic E. coli
O157:H7 cells amid increasing concentrations of innocuous E. coli DH5α cells. With their
numerous advantages over traditional organic dyes, semiconductor QDs should also be
advantageous in high-throughput techniques such as flow cytometry. Indeed, use of QDs
to label the pathogenic serotype showed greater detected percentages of labeled cells,
higher fluorescence intensities, and lower limits of detection (1%) compared to an
analogous labeling done with FITC. The particular biochemical interactions and surface
82
Oral Abstracts
functionalizations incorporated in these methods can easily be generalized to allow for the
rapid and selective detection of other common pathogens.
D2 – Invited Paper
A GENERIC APPROACH TO BIOMOLECULAR FUNCTIONALITY ON GOLD
AND SILVER NANOPARTICLES
Robert T. Tshikhudo,a,b Jennifer L. Brennan,a Claire Rees,a Zhenxin Wang a and
Mathias Brust a; aNanoscale Science Centre, Chemistry Department, The University
Of Liverpool, Liverpool, L7 7ZD, UK, bProject AuTEK, Advanced Materials
Division, Mintek, Private Bag X 3015, Randburg, 2125, South Africa;
t.r.tshikhudo@liv.ac.uk
78
The exploitation of monolayer protected clusters (MPC s) of gold and to a lesser extent silver, is
rapidly advancing both in applied and fundamental research due to their ease of preparation,
extreme stability and tunable optical properties. It is generally understood that the extreme
stability of these materials is conferred by the thiolate-ligands, which form a protective shell
around the particles to which they are attached via strong Ag/Au-S interaction. The optical
properties of the particles are controlled by particle size, shape and state of aggregation. Since
most MPCs are not water-soluble, significant effort to overcome this limitation has recently been
made with the aim to make them suitable for biological applications. To explore the usefulness of
these materials, particularly in biomedical and/or pharmaceutical areas, it is vital to introduce
specific functionalities, which will address potential applications in these areas. To combine
excellent water solubility, stability and functionality of MPCs, we have developed a generic
approach to introduce biomolecular functionality such as proteins and oligonucleotides on Au
and Silver nanoparticles. Here we present the facile synthesis of these hydrophillically
functionalised Au and Ag nanoparticles, with special emphasis on their ease of preparation and
functionalisation. The versatility of these functional MPCs is highlighted. This includes the
ability to demonstrate that the attached biomolecules retain their functionality, for example, in the
case of attaching enzymes to an MPC ligand shell. These particles are ideal candidates for use as
drug and/or gene carrier, as bio-labels and for large-scale diagnostic purposes, and it is possible to
introduce specific recognition capabilities of choice.
D2 – Invited Paper
EPITOPE PRESENTATION ON GOLD NANOPARTICLES FOR
IMMUNOASSAY DEVELOPMENT
David E. Cliffel, Aren Gerdon, Brian Huffman, David W. Wright, Department
of Chemistry, Vanderbilt University, Nashville, TN 37235-1822, USA;
d.cliffel@vanderbilt.edu
79
Monolayer protected clusters provide a unique nanoparticle structure for the exploration of
the biological interactions. With a central metal core surrounded by a protecting thiolate
ligand, the clusters allow for a combination of functions similar to that of many
biomacromolecules like many proteins. One of the key chemical functions of biological
systems that we can hope to mimic is antibody-antigen interactions using epitope
83
Oral Abstracts
presentation on the nanoparticle. This talk will present our recent progress in these areas
by creating antigenic nanoparticles for antibody recognition. Initial studies with
glutathione protected gold clusters demonstrated binding of polyclonal anti-glutathione
antibodies to the nanoparticle using the quartz crystal microbalance technique. Progress
includes successful efforts to create nanoparticles that show strong binding to monoclonal
antibodies against specific peptide target epitopes recreated on the nanoparticle surface.
These peptide-functionalized nanoparticles simulate the antibody binding site, i.e. the
epitope for two specific diseases. The first epitope, hemaggluttatin, is abundantly present
on the surface of influenza virus and is a linear epitope of 6 amino acids. The second
epitope is based on the protective antigen protein of bacillus anthracis infection. This
second epitope has been explored in both a linear and loop configuration the cluster, with
the stronger binding observed in the loop configuration suggesting a conformational
epitope that involves creation of peptide secondary structure off of the cluster surface. An
immunoassay using the quartz crystal microbalance and epitope presenting clusters has
been developed for antibody diagnostics in patient sera.
D2 – Contributed Paper
SURFACE MODIFICATION OF PARTICLES ENHANCES
INTRACELLULAR UPTAKE
Volker Mailänder, Myriam Kern, Karin Nothelfer, Institute for Clinical
Transfusion Medicine and Immunogenetics Ulm, Department of Transfusion
Medicine, University of Ulm, 10 Helmholtzstr., Ulm 89081, Germany; Anna
Musyanovych, Verena Holzapfel, Katharina Landfester, University of Ulm,
Department of Organic Chemistry III / Macromolecular Chemistry, 11
Albert-Einstein-Allee, Ulm 89081, Germany; v.mailaender@blutspende.de
80
Labeling of cells with nanoparticles for in-vivo detection is interesting for various
biomedical applications e.g. labeling of cells with superparamagnetic nanoparticles. The
objective of this study was to evaluate the feasibility and efficiency of labeling cells with
particles without using transfection agents. We hypothesized that surface charge would
influence cellular uptake. The particles were synthesized by the miniemulsion process. A
hydrophobic fluorescent dye was embedded in these nanoparticles and served as reporter.
As most transfection agents are positively charged molecules we synthesized particles with
different surface charge by adjusting the amount of copolymerized monomers with amino
groups thus enabling to study the cellular uptake in correlation to this parameter. Uptake of
the particles or attachment of nanoparticles were detected by FACS measurements. This
was performed in four different cell lines: mesenchymal stem cells (MSC), HeLa, Jurkat,
and KG1a. These cell lines were chosen as they can serve as models for clinically
interesting cell types. For these cell lines - with the exception of MSCs - a clear correlation
of surface charge and fluorescence intensity was shown. Most interestingly no transfection
agents which are not approved for in-vivo application in humans were needed for an
efficient uptake of the particles. As FACS cannot differentiate between extracellular and
intracellular localization and subcellular localization we used confocal laser scanning
microscopy (LSM) and transmission electron microscopy (TEM) to reveal differences in
subcellular localization of the particles. In MSCs and HeLa particles were mostly located
84
Oral Abstracts
inside of cellular compartments resembling endosomes, while in Jurkat and KG1a,
particles were predominantly located in clusters on the cell surface. Scanning electron
microscopy showed microvilli to be involved in this process.
I1 –Keynote Paper
POLYMERIC MICELLES: POTENTIAL AS PHARMACEUTICAL
NANOCARRIERS
Vladimir P. Torchilin, Department of Pharmaceutical Sciences, Northeastern
University, Boston, MA 02115, USA; v.torchilin@neu.edu
81
Micelles represent an important class of nanocarriers for poorly soluble pharmaceuticals.
Among polymeric micelles, micelles formed by amphiphilic polymer-lipid conjugates
(such as polyethyleneglycols or polyvinylpyrrolidones conjugated at one terminus with
lipid residues) are of a special interest because they form very stable micelles with low
CMC values. These micelles maintain stability upon dilution and in biological fluids,
demonstrate prolonged circulation times in vivo (mice, rats, rabbits), and can be effectively
loaded (from 5 to 50 % by weight) with various poorly soluble pharmaceuticals, such as
various anticancer drugs (taxol, tamoxifen, camptothecin, porphyrins) or hydrophobic and
amphiphilic diagnostic agents. Drug-loaded micelles demonstrate an increased
accumulation in experimental tumors and infarcts via the enhanced permeability and
retention (EPR) effect. The potential of polymeric micelles as pharmaceutical carriers may
be still further improved by attaching targeted ligands including specific antibodies, to the
micelle surface. Using polyethylene glycol-phosphatidyl ethanolamine (PEG-PE)
conjugate activated at its distal water-exposed end with the p-nitrophenylcarbonyl (pNP)
group, pNP-PEG-PE, as a micelle component, we have been able to attach to micelles
various monoclonal antibodies (monoclonal tumors-specific 2C5 anti-nucleosome
antibody and monoclonal infarct-specific 2G4 anti-myosin antibody). Anticancer drug
(taxol)-loaded 2C5 antibody-bearing micelles provided a sharp increase in killing cancer
cells in vitro and in tumor models in mice. Preferential accumulation of plain and targeted
micelles loaded with various therapeutic or diagnostic agents in experimental tumors and
areas of experimental myocardial infarction in animals was also demonstrated.
Polymer-lipid-based micelles and immunomicelles represent a new family of convenient
nanocarriers for poorly soluble pharmaceuticals.
I1 – Invited Paper
SELF-ASSEMBLY OF SURFACTANT AIDED DELIVERY SYSTEMS
Lise Arleth, Rex P. Hjelm, Los Alamos Neutron Science Center, Los Alamos
National Laboratory; Beena Ashok and Hyat Onyuksel, Department of
Biopharmaceutical Sciences, College of Pharmacy, University of Illinois,
Chicago; hjelkm@lanl.gov
82
Advanced drug delivery systems based on self-assembled surfactant particles require
detailed understanding of the factors controlling size and shape, to tailor the particles and
predict their behavior with drug loading and in vivo. Among the factors that may control
85
Oral Abstracts
particle morphology is the inherent interfacial curvature of surfactants and the free energy
required to bend the interface. A key idea underlying considerable theoretical and
modeling work is that inherent interfacial curvature can be controlled by mixing
surfactants with different inherent curvature. Although this idea is in qualitative agreement
with observation, there is not sufficient experimental work to validate the models
quantitatively. We studied aqueous suspensions of mixed surfactants with different
inherent curvature, egg yolk phosphaticylcholine (PC) and poly(ethyleneglycol) (PEG)
modified distearoyl phospatidylethanolamine (DSPE), at molar mixing ratios from 0:100
to 30:70 (DSPE-PEG:PC) using PEG with molar mass of either 2 or 5 kDa,. We used
neutron, x-ray and light scattering data on particle morphology for comparison with
theoretical predictions. Considerable latitude in controlling the particle shape was found.
At high DSPEPEG:PC ratios, spheroid micelles were formed. As the PC content was
increased, the micelles became elongated to tri-axial prolate ellipsoids. At a DSPEPEG:PC
molar ratio of 30:70 rodlike micelles longer than 1000 Å were formed. In all cases the
micelle internal structure consisted of a hydrophobic core, surrounded by a dense
hydrophilic layer of PC heads condensed with part of the PEG chain. The outer layer
consisted of the remaining part of the PEG chains in overlapping Gaussian random coils.
The data gave quantitative agreement with an existing model, but showed that the
mushroom to brush transition of PEG, suggested by other work, is not a likely determinant
of interfacial curvature. We discuss the implications of this work for tailored particle
delivery of sparingly soluble drugs.
I1 – Invited Paper
POLYMERIC MICELLES FOR TUMOR TARGTED DELIVERY OF
P-GLYCOPRTEIN INHIBITORS
Afsaneh Lavasanifar, Hamidreza Montazeri Aliabadi, Dion R. Brocks,
Faculty of Pharmacy & Pharmaceutical Sciences, University of Alberta,
Edmonton, AB, Canada T6G 2N8; alavasanifar@pharmacy.ualberta.ca
83
One of the major causes of failure in cancer treatment is multi-drug resistance (MDR),
where cancer cells simultaneously become resistant to different anticancer drugs.
Over-expression of membrane efflux pumps like P-glycoprotein (P-gp) that recognizes
different chemotherapeutic agents and transports them out of the cell, plays a major role in
MDR. P-gp inhibitors have shown little benefit in overcoming drug resistance in clinic
because systemic administration of P-gp inhibitors will reduce the elimination of P-gp
substrates (e.g., anticancer drugs) from healthy cells that overexpress P-gp leading to
intolerable toxicities by anticancer drugs. The objective of this research is to develop a
tumor targeted carrier that permits specific delivery of P-gp inhibitors to tumorogenic
P-gp. Polymeric micelles have shown promise in tumor targeted delivery of hydrophobic
drugs. Although P-gp inhibitors are structurally diverse, they share the physicochemical
property of lipophilicity necessary for plasma membrane penetration. This makes them
ideal candidates for incorporation in polymeric micelles. We have focused on
self-associating poly(ethylene oxide)-b-poly(ε-caprolactone) (PEO-b-PCL) block
copolymers as biodegradable polymeric nanocarriers for tumor targeted delivery of P-gp
inhibitors. PEO-b-PCL copolymers were assembled to carriers of 80-100 nm, caused a 100
86
Oral Abstracts
fold increase in the aqeous solubility of CsA and retained 94 % of their drug content after
24 h. In healthy rats, a 6.1 fold increase in the blood AUC was observed for polymeric
micellar CsA compared to commercial formulation of CsA. PEO-b-PCL micelles reduced
uptake of encapsulated CsA by kidney and caused a reduction in the nephrotoxicity of
CsA. The creatinine clearance was lowered (1.9 fold) by the commercial formulation but
did not change when polymeric micellar CsA was injected for 7 days. Polymeric micelles
caused 1.7 and 2.5 fold increases in the blood and tumor concentrations of CsA,
respectively, in Lewis Lung Carcinoma (LLC1) bearing mice. Further studies are
underway to define whether tumor targted delivery, would lead to an increased therapeutic
benefit for P-gp inhibitors.
I1 - Invited Paper
ENGINEERING COPOLYMER MATERIALS AND MICELLES FOR
TARGETED DELIVERY OF HYDROPHOBIC DRUGS
C. Allen, Faculty of Pharmacy, University of Toronto, 19 Russell St., Toronto,
ON, M5S 2S2, cj.allen@utoronto.ca
84
Block copolymer micelles have gained increasing attention as a viable formulation strategy
for hydrophobic drugs. The micelles may serve as solubilizers and/or true drug carriers
depending on their stability and drug retention properties in vivo. Polymeric micelle
systems have been shown to increase the aqueous solubility of hydrophobic drugs up to 30
000 fold. Micelle systems have also been shown to enhance the circulation lifetime and
reduce the systemic toxicity of some drugs. The full exploitation of micelles as a
formulation and/or carrier technology requires a firm understanding of the relationships
between the properties of the copolymer, the physico-chemical properties of the micelles
and their performance (i.e. drug loading capacity, drug retention properties,
pharmacokinetics profile, biodistribution). Recent research efforts in our laboratory have
demonstrated that block copolymer micelles have great potential for use in the targeted
delivery of hydrophobic drugs. Firstly, it has been found that micelles may be designed to
retain their stability in vivo even at copolymer concentrations below the critical micelle
concentration of the material. Our studies have characterized the in vivo distribution
kinetics and fate of copolymer following i.v. administration of 1) copolymer assembled as
thermodynamically stable micelles, 2) copolymer assembled as thermodynamically
unstable micelles and 3) copolymer single chains. Secondly, targeted micelles may be
successfully prepared by conjugation of specific ligands to the surface of micelles.
Specifically, the epidermal growth factor (EGF) was attached to the micelle surface and the
EGFR-targeted micelles were found to localize in the perinuclear region as well as the
nucleus of EGFR-overexpressing breast cancer cells. The EGFR-targeted delivery system
may not only serve to increase the overall intracellular accumulation of an encapsulated
agent, but may also allow for the delivery of agents to the perinuclear or nuclear regions of
the cell. Overall, findings from these studies demonstrate the ability to tailor block
copolymer micelles for effective targeted delivery of specific hydrophobic drugs.
87
Oral Abstracts
I1 – Invited Paper
NANODELIVERY USING BLOCK COPOLYMERS: A PROPOFOL
SOLUTION
François Ravenelle, Labopharm Inc., 480 Blvd Armand-Frappier, Laval,
Québec H7V 4B4, Canada; fravenelle@labopharm.com
85
A novel bacterio-static and lipid free, nanocarrier [poly(N-vinyl-2-pyrrolidone)-blockpoly(D,L-lactide) copolymer] formulation of propofol has been developed that addresses
the deficiencies of currently available versions. The formulation is presented as a
lyophilized cake which reconstitutes instantly in all aqueous media to produce a clear
liquid that is both filterable and compatible with commonly used infusion media. The
reconstituted solution is stable over a wide range of ionic strengths, pH and drug
concentrations and has been shown to remain stable for more than 5 days after
reconstitution. Non-clinical studies in rats have shown the formulation possesses
pharmacokinetic and pharmacodynamic properties equivalent to Diprivan(r).
I1 – Invited Paper
TUMOR TRIGGERED ACTIVATION AND RELEASE OF DRUGS FROM
LIPID BASED DRUG AND PRODRUG NANOCARRIERS
Kent Jørgensen, LiPlasome Pharma A/S, Technical University of Denmark,
Building 207, DK-2800 Lyngby, Denmark; and Thomas L. Andresen,
LiPlasome Pharma A/S, Technical University of Denmark, Building 207,
DK-2800 Lyngby, Denmark; jorgense@liplasome.com
86
The selectivity of anticancer drugs in targeting the tumor tissue presents a major problem
in cancer treatment. We report a new generation of liposomal nanocarriers that can be used
for enhanced anticancer drug and prodrug delivery to tumors. The liposomes are
engineered to be particularly degradable to secretory phospholipase A2 (sPLA2), which is
a phospholipid hydrolyzing enzyme that is significantly upregulated in the extracellular
microenvironment of cancer tumors. Thus, when the long circulatory liposomal
nanocarriers extravasate and accumulate in the interstitial tumor space, sPLA2 will act as
an active trigger resulting in the release of cytotoxic drugs in close vicinity of the target
cancer cells. The local degradation of the phospholipids by sPLA2 in the tumor results in
the generation of lysolipid and fatty acid hydrolysis products, which advantageously can
function as locally released membrane permeability promoters facilitating the intracellular
drug uptake. In addition, the liposomal membrane can be composed of a novel class of
prodrug phospholipids that can be converted selectively to active anticancer agents by
sPLA2 in the tumor. The integrated drug discovery and delivery technology offers a
promising way to rationally design novel tumor activated liposomal nanocarriers for better
cancer treatment.
88
Oral Abstracts
J1 – Invited Paper
NON-CROSSLINKING AGGREGATION OF DNA-CARRYING
NANOPARTICLES FOR GENE DIAGNOSIS
Mizuo Maeda, RIKEN Institute, Bioengineering Lab., Hirosawa, Wako
351-0198, Japan; mizuo@riken.jp
87
We developed a reliable method for detecting single nucleotide mutation by using
spontaneous aggregation of a DNA-carrying colloidal nanoparticle, which was made from
poly(N-isopropylacrylamide) (polyNIPAAm) grafted with probe DNA chains. The
particle with the diameter of 50 nm was formed through self-assembly of
polyNIPAAm-graft-DNA copolymers above the phase transition temperature (ca. 36
degree C) of polyNIPAAm part. The particle was determined to consist of 20 graft
copolymers each of which has 10 graft chains of the probe DNA, suggesting that one
particle has 200 probes on it. When adding the complementary DNA of the equimolar
amount into the colloidal dispersion, the particles were found to aggregate within a minuite
in buffer (pH 7.4) containing 0.5M NaCl through the salt concentration-dependent
aggregation. In contrast, they kept dispersing in the presence of the one point-mutated
DNA under the identical conditions. Interesting and important is that the phenomenon is
extraordinary sensitive to the terminal mismatch of duplex formed on the particle. The
results demonstrated that the non-crosslinking aggregation of DNA-carrying nanoparticles
is useful for analyzing various SNPs when coupled with the primer extention assay. The
core material is not restricted to PNIPAAm; DNA-functionalized gold nanoparticle (15 nm
diameter) was found to show a similar aggregation phenomenon induced only by the
fully-complementary DNA, resulting in rapid color change within 3 min at ambient
temperature. This methodology is general in principle and applicable for wide variety of
clinical diagnosis.
J1 - Invited Paper
GLUATATHIONE DEGRADADABLE AND pH MODULATABLE
POLYCATION/DNA NANOPLEXES FOR GENE DELIVERY
Cameron Alexander,a Jon A Preeceb and Len Seymourc, a School of Pharmacy,
University of Nottingham; bSchool of Chemistry, University of Birmingham;
c
Department of Clinical Pharamacology, University of Oxford, United
Kingdom; j.a.preece@bham.ac.uk
88
The potential benefits of successful gene therapy cannot yet be fully realised, mainly
because of difficulties of gaining adequate delivery and expression of therapeutic
transgenes. This research aims to develop an efficient, fully defined and safe system for
delivery of DNA and RNA to cells, based on novel self-assembled polyplexes (colloidal
polycation/nucleic acid particles). The polyplexes will be bio-responsive, designed to
combine stability during the extracellular delivery phase with triggered intracellular
destabilisation to maximise activity of the contained nucleic acids. The work will
encompass a number of aspects vital to the development of new vectors for gene delivery,
including modulation of synthetic vector-nucleic acid binding, transport of polyplexes
89
Oral Abstracts
through cell membranes and triggered release of nucleic acids within the cytoplasm and/or
nucleus. Specifically, we will:
(i) Synthesise a series of cationic polymers based on basic poly(amino acids) and
correlate their chemical properties with the physicochemical properties of the
polyplexes they form with nucleic acids, with a view to maximising their
endosomolytic activity,
(ii) Evaluate the design of polyplexes for triggered intracellular destabilisation, by
reduction, to enable intracellular release of the nucleic acid and achieve maximal
therapeutic activity,
(iii) Examine the incorporation of thiol-bearing targeting agents (to endow endothelial
cell-selectivity) and endosome-escape agents (e.g. melittin-SH) to maximise
cell-specific biological activity.
The proposed programme requires a multidisciplinary approach, including organic and
polymer synthesis, biomolecular recognition, molecular biology and pharmacology, and
combines the research of three complementary academic groups. The results from this
project will have relevance in fields varying from pharmaceutical chemistry to cell biology
and medicine. The presentation will detail progress made to date.
J1 – Contributed Paper#
LIPID PHASE CONTROL OF DNA DELIVERY
Rumiana Koynova, Li Wang, Robert C. MacDonald, Department of
Biochemistry, Molecular & Cell Biology, Northwestern University, Evanston,
IL 60208, USA; r-tenchova@northwestern.edu
89
Cationic lipids form nanoscale complexes (lipoplexes) with polyanionic DNA, and can be
used to deliver DNA to cells for transfection. Lipid-mediated DNA delivery (lipofection)
is now considered highly promising, but its mechanism is still largely unknown, and the
transfection efficiency is unsatisfactorily low for many cell types. Understanding the
mechanism of gene delivery by cationic liposomes is thus of utmost importance for
effective gene therapy. Here we report a correlation between the delivery efficiency of
cationic phospholipid DNA carriers and the mesomorphic phase behavior of their mixtures
with negatively charged membrane lipid compositions. Specifically, formulations that are
particularly effective DNA carriers, form nonlamellar phases of highest negative
interfacial curvature (micellar, hexagonal, cubic) when mixed with negatively charged
membrane lipids, whereas less effective formulations form phases of lower curvature;
moreover, this is true when the mixed cationic/membrane lipid aggregates exhibit the
lamellar-nonlamellar phase transition within the physiological temperature range, ~37°C.
Lipid vehicles are well known to exhibit maximum leakiness and contents release in the
vicinity of phase transitions, especially those involving nonlamellar phase formation.
Structural evolution of the carrier lipid/DNA complexes upon interaction with cellular
lipids is hence proposed to be a controlling factor in lipid-mediated DNA delivery. A
strategy for optimizing lipofection is deduced: Lamellar lipoplex formulations with
compositions close to the lamellar-nonlamellar phase transition, which could easily
undergo such a transition upon mixing with membrane lipids, are especially promising
lipoplex candidates. The ability to rationally assess critical structural characteristics and
90
Oral Abstracts
phase behaviors of lipoplex components would represent an unprecedented step forward
for this form of gene therapy vector.
J1 – Invited Paper
GENE DELIVERY AND QUANTUM DOT ASSISTED INTRACELLULAR
TRAFFICKING
Charudharshini Srinivasan,1 Jeunghoon Lee2, Fotios Papadimitrakopoulos2,
Lawrence K. Silbart3, and Diane J. Burgess1. 1Dept of Pharmaceutical
Sciences, 69 North Eagleville Road, Unit 3092, 2Institute of Materials Science,
97 North Eagleville Road, Unit 3136, 3Dept. of Animal Science, 1390 Storrs
Road, Unit 4163, University of Connecticut, Storrs, CT 06269, USA]
d.burgess@uconn.edu
90
Despite their low transfection efficiencies, non-viral vectors (such as, cationic and anionic
lipids, cationic polymers and polymeric nanoparticles) are actively being pursued as a
means of gene delivery due to their low immunogenicity and low toxicity in comparison to
viral vectors. To better understand and improve transfection efficiency, it is essential to
quantify the processes involved in cellular uptake and trafficking of exogenous DNA into
nucleus. Semiconductor nanocrystal quantum dots (QDs) are excellent candidates for
fluorescent tagging in biological applications since they display long-term resistance to
photobleaching. A novel method of QD-DNA conjugation is presented that allows
long-term tracking of DNA within the cellular environment. Cadmium selenide/zinc
sulphide QDs were encapsulated in maleimide functionalized PEG-PE2000. Plasmid DNA
labeling with QDs was achieved using a SPDP-PNA linker. Photostability of QD-DNA
conjugates were compared to DNA complexes with the organic dye, rhodamine. Time
lapse imaging experiments were performed using a confocal laser scanning microscope
(Leica SP2 Spectral Confocal Microscope). Transfection of QD-DNA conjugates
(enhanced green fluorescent protein (EGFP)) was conducted in CHO-K1 cells in the
presence of LipofectamineTM2000. QD-DNA labeling was confirmed by AFM imaging.
Clusters of QDs were observed on the plasmids presumably at the PNA binding site. The
QD-DNA conjugates were photostable throughout a 100 min continuous laser excitation
study in in vitro cell culture. The QD-DNA conjugates were capable of expressing the
reporter protein (EGFP) allowing simultaneous tracking of plasmid DNA at the subcellular
level. Quantification of EGFP expression revealed 68% transfection efficiency for the
QD-DNA conjugates which is comparable to control plamid DNA (72% transfection
efficiency), indicating no loss of activity on conjugation. Acknowledgements: The
authors thank Minhua Zhao and Shafiuddin Shafiuddin, University of Connecticut for
technical assistance. This research was supported in part by a Parenteral Drug Association
Foundation Schering-Plough Grant.
J1 – Invited Paper
MULTIFUNCTIONAL NANOPARTICLES FOR IMAGING ASSISTED
GENE THERAPY
Yong Zhang, Wee Beng Tan, Division of Bioengineering, Faculty of
91
91
Oral Abstracts
Engineering, National University of Singapore, 9 Engineering Drive 1,
Singapore 117576; biezy@nus.edu.sg
There has been immense interest in luminescent nanocrystals due to their ideal optical
properties and promising applications in fields such as biological labelling. In particular,
these luminescent nanocrystals have been exploited for their superb optical properties,
such as excellent photostability and high quantum yields, in their use as biological labels
over conventional organic flourophores. However, as most of them are prepared in an
organic medium and are not soluble in water, they are not suited for any bio-applications.
Furthermore, these nanocrystals are not biocompatible. To overcome these problems,
different polymerization techniques to incorporate the nanocrystals into polymer
microbeads have been used and reported. While these microbeads are generally very useful
for multiplexed immunoassays, they are not suitable for the staining or labeling of
subcellular components or intracellular measurements as they are relatively large in size. In
this work, biocompatible chitosan nanobeads encapsulating luminescent nanocrystals were
prepared, which can be used as fluorescent markers for immunoassay/cell labeling.
Chitosan is a biopolymer with amino and hydroxyl groups on the surfaces that can be used
for further attachment of biomolecules. Furthermore, as chitosan beads are very small, they
can be used to label subcellular components such as intracellular proteins or to study the
intracellular delivery of nanoparticles. At the same time, chitosan has also been widely
used to deliver therapeutic genes by intravenous, oral and mucosal administration.
However, the biodistribution of nanoparticles and the mechanism of their delivery to cells
and tissues remain unclear. Using the multi-functional chitosan nanobeads developed,
imaging techniques can be used to study the biodistribution of nanoparticles and their
intracellular pathway, and the same results can be used for the delivery of genes or other
drugs, using chitosan as a carrier.
J1 – Contributed Paper
CLUSTER ASSEMBLED NANOSTRUCTURED TIO2 FILM MEDIATES
EFFICIENT AND SAFE RETROVIRAL GENE TRANSDUCTION IN
PRIMARY ADULT HUMAN MELANOCYTES FOR EX-VIVO GENE
THERAPY
Roberta Carbone, Ida Marangi, Andrea Zanardi, Luisa Lanfrancone, Saverio
Minucci, Pier Giuseppe Pelicci, European Institute of Oncology, Via
Ripamonti 435, I-20141 Milan, Italy; and Luca Giorgetti, Elisabetta Chierici,
Gero Bongiorno, Paolo Piseri, Paolo Milani, CIMAINA and Dipartimento di
Fisica, Università di Milano, Via Celoria 16, I-20133 Milan, Italy;
paolo.milani@mi.infn.it
92
Primary human melanocytes represent the precursor cells to melanoma and also specific
targets of inherited and acquired pigmentation disorders. The possibility to genetically
manipulate these cells for biological studies or therapy has not been fully exploited for the
lack of efficient and safe stable gene transfer techniques. We have developed a new gene
transfer technology on primary adult human melanocytes by means of retroviral infection
in absence of any toxic polycations currently employed to improve infection efficency (i.e.
92
Oral Abstracts
polybrene). We demonstrate that this polycation induce apoptosis and DNA damage
through ATM phosphorylation, causing a further genetic perturbation to cells. We have
cultured primary human melanocytes on a biocompatible nanostructured TiO2 film,
obtained by the deposition of a supersonic beam of titania clusters, coated by retroviral
vectors expressing GFP. By means of a “reverse infection “ mechanism we achieved 80%
of infection in absence of any toxic effect. This high efficiency is related to the interaction
of retroviral vectors and cells with the nanoparticle-assembled substrates. We expect that
such technology based on nanostructured surfaces will allow efficient and safe genetic
manipulation of primary cells for ex-vivo gene therapy.
J1 – Contributed Paper
JC VIRUS-LIKE PARTICLES: SIZE DEPENDENT IN VITRO DNA
PACKAGING AND GENE DELIVERY
Oliver Ast, Andrezj Citkowicz Linda Cashion, Brent Larsen, Richard N.
Harkins, and Harald Petry, Departments of Gene Therapy Research and
Pharmacology, Berlex Biosciences, Richmond, CA, USA;
Harald_Petry@Berlex.com
93
Virus-like particles (VLP) are known to be a promising alternative to the existing viral and
non-viral DNA delivery systems but also have been used to deliver RNA and small
molecules. VLPs are self-assembled structures composed only of proteins necessary for
capsid formation and DNA packaging. They are replication deficient and exhibit a similar
morphology and cell tropism compared to their viral origin. One of the major differences
between VLPs and traditional viral vector systems is the manner in which DNA is
packaged. For viral delivery systems the use of packaging cell lines is indispensable
whereas the DNA packaging into the VLP can be accomplished by controlled and
reproducible in vitro methods. In this study we present an in vitro protocol to package
plasmid DNA into JCV-derived VP1-VLP. JCV is a non-enveloped virus with a 50nm
icosahedric capsid containing three proteins VP1, VP2 and VP3 enclosing the viral
genome of 5kb. It has been shown that the expression of the major structural protein VP1 is
sufficient to generate VLPs with the same size and morphology as the original JCV.
VP1-VLPs were dissociated into VP1 pentamers before DNA packaging. In the presence
of DNA the pentamers reassembled efficiently into VLPs in a CaCl2 containing buffer.
VLPs packaged with a 5 kb EGFP expression plasmid were successfully used for cell
transfection. Analytical characterization of the VLPs indicated a 2.5 fold increase in size
compared to JC-virus. After DNase treatment however, the particles showed the expected
size of 50nm but transfection efficiency was reduced. A 1.6 kb DNA fragment expressing
GFP was then used to investigate if smaller DNA molecules are packaged more efficiently.
The 1.6 kb fragment was efficiently packaged, the DNA was DNase resistant and VLPs
showed the expected size. The transfection efficiency of VLPs packaged with the 1.6kb
fragment was higher compared to the VLPs packaged with the original 5kb plasmid. The
packaging and DNA delivery efficiency of the 5kb EGFP expression plasmid could be
significantly increased by condensing the DNA used for packaging with histones. In this
study we describe a simple and reproducible in vitro method to efficiently and
quantitatively package DNA into JCV derived VP1-VLPs that results in high transfection
efficiency.
93
Oral Abstracts
J1 – Invited Paper
WELL-DEFINED CORE-SHELL NANOPARTICLES WITH BRANCHED
POLY(ETHYLENIMINE) SHELLS AS EFFICIENT GENE DELIVERY
CARRIERS
Lijun Li, Man Fai Leung, Junmin Zhu,1 Angie Tang, 1 Lai Pang Law,1 Min
Feng1, Kin Man Ho1, Daniel K. L. Lee1, Frank W. Harris,2 Pei Li1
Department of Applied Biology and Chemical Technology, The Hong Kong
Polytechnic University, Hung Hom, Kowloon, P. R. China;
bcpeili@polyu.edu.hk; 2Maurice Morton Institute of Polymer Science,
University of Akron, Ohio, USA
94
Spherical, well-defined core-shell nanoparticles that consist of poly(methyl methacrylate)
(PMMA) cores and branched poly(ethylenimine) shells (b-PEI, 25kDa) were prepared in
aqueous in the absence of surfactant. The PMMA-PEI core-shell nanoparticles were
approximately 150 nm in diameters, and displayed zeta-potentials above +40 mV. Plasmid
DNA (pDNA) could effectively complex onto the nanoparticles in various biological
mediums, and average diameter of the complexed particles was approximately 100 to 120
nm with high homogeneity. The complexing ability of the nanoparticles was strongly
dependent on the molecular weight of the PEI and the thickness of the PEI shells. The
stability of the complexes was influenced by the loading ratio of the pDNA and the
nanoparticles. The condensed pDNA in the complexes was significantly protected from
enzymatic degradation by DNase I. Cytotoxity studies suggested that the PMMA-PEI
core-shell nanoparticles were three times less toxic than the b-PEI polymer (25 kDa).
Transfection efficiencies of both PMMA-PEI nanoparticles and b-PEI polymer were
evaluated at different N/P ratio, transfection time, cell density and cell line. Furthermore,
investigation of the intracellular behavior of FITC-labeled pDNA/nanoparticles using a
flow cytometric analysis indicated that the PMMA-PEI nanoparticles were effective
carriers to deliver the pDNA into cells.
Plenary 2
95
PROGRESS IN PHOTONIC CRYSTAL CLINICAL SENSORS
Sanford A. Asher, Jeremy P. Walker, Kyle W. Kimble, Michelle M.
Muscatello and Matti Ben-Moshe, University of Pittsburgh, Department of
Chemistry, Pittsburgh, PA 15260, USA; asher+@pitt.edu
We have been developing a new clinical sensing technology based on crystalline colloidal
arrays embedded in hydrogels. These photonic crystal materials diffract light. We add
molecular recognition agents to these materials which actuate volume phase transitions
that shift the spacing between particles which shifts the wavelength of the diffracted light.
We will review our progress in developing new sensors which can be used in point-of-care
bedside clinical chemical applications.
94
Oral Abstracts
A3 – Invited Paper
CHARACTERIZATION AND BIOLOGICAL APPLICATIONS OF
COLLOIDAL NANOPARTICLES
Wolfgang J. Parak, Center for Nanoscience, Ludwig Maximilians Universität
München, Amalienstraße 54, 80799 München, Germany;
Wolfgang.Parak@physik.uni-muenchen.de
96
Colloidal quantum dots are semiconductor nanocrystals well dispersed in a solvent. The
optical properties of quantum dots, in particular the wavelength of their fluorescence,
depend strongly on their size. Because of their reduced tendency to photobleach, colloidal
quantum dots are interesting fluorescence probes for all types of labeling studies. In this
review we will discuss the biological relevant properties of quantum dots and focus on the
following topics: 1) How can individual nanoparticles be modified with an exactly
controlled number of biological molecules. 2) How can nanoparticles of different
materials be used for drug delivery. Also biocompatibility issues will be discussed.
A3 – Invited Paper
BIOMIMETIC PROCESSING METHODS FOR ORGANIC-INORGANIC
PARTICLES
Vishal M. Patel, Chelsea M. Magin, and Laurie B. Gower, Department of
Materials Science & Engineering, University of Florida, Gainesville, FL, USA;
lgowe@mse.ufl.edu
97
“Soft”-“Hard” Core-shell particulate systems are being developed for use in
pharmaceutical and other controlled release and uptake applications. The technology is
based on the ability to deposit coatings of a “hard” mineral shell composed of calcium
carbonate onto “soft” emulsion colloids. These robust composite particles are prepared
using a biologically-inspired mineralization process, in which soluble acidic polymers act
as process-directing agents to generate droplets of a fluidic mineral precursor which
selectively adsorb onto the charged surface of surfactant stabilized oil droplets. The
amorphous mineral precursor encapsulates the oil-filled colloid, and then solidifies and
crystallizes into a uniform crystalline shell of calcite. Core-shell particles on the order of 1
to 4 μm have been successfully synthesized. The metastable structure of the calcium
carbonate makes it biodegradable, as well as biocompatible, providing a novel system for
controlled release applications. The particles bear a striking resemblance to our biological
inspiration, dinoflagellate cysts, in which the unicellular organism encapsulates itself
within a porous CaCO3 shell. We are now seeking to mimic the organism’s ability to
regulate porosity in the mineral shell, which would be valuable for controlled uptake
applications, such as in toxicity reversal of drug overdose, which requires rapid removal of
toxins from the bloodstream. In this case, the mineral shell needs to be a porous molecular
filter, such that when the particles are introduced into the bloodstream, the oil-based core
can sequester toxic levels of lipophilic drugs. Using a phase-segregated binary amphiphile
system, we have been able to demonstrate that porosity can be templated on flat
free-standing mineral films deposited at the air-water interface of Langmuir monolayers.
95
Oral Abstracts
Next, we hope to transfer this organic-inorganic templating approach to the core-shell
particles, ultimately enabling the high degree of morphological control found in biomineral
systems.
A3 – Contributed Paper
HYALURONAN-BASED HYDROGEL MICROSPHERES FOR VOCAL
FOLD REGENERATION
Xinqiao Jia, Dept. of Mater. Sci. & Eng., University of Delaware, Newark, DE
19716; Yoon Yeo, Robert Langer, Dept. of Chem. Eng., Massachusetts
Institute of Technology, Cambridge, MA 02139; Rodney J. Clifton, Tong Jiao,
Div. of Eng., Brown University, Providence, RI, 02912; Daniel S. Kohane and
Steven M. Zeitels, Massachusetts General Hospital, Boston, MA 02114;
xjia@udel.edu
98
Vocal fold vibration depends critically on the viscoelasticity of the connective tissue of the
vocal fold mucosa. Voice abuse or overuse can lead to scarring that disrupts the natural
pliability of the lamina propria and results in vocal dysfunction. An estimated 5-10% of
the population is affected by some degree of vocal fold scarring. Despite a well-recognized
clinical need for a material to replace missing or damaged vibratory connective tissue of
the vocal fold, materials have yet to be engineered specifically for this purpose. We have
developed hyaluronan (HA)-based soft hydrogel microspheres (microgels) as an injectable
remedy for vocal fold regeneration. Chemical modification of HA led to quantitative
introduction of mutually reactive functional groups (hydrazide HA-Hdz and aldehyde
HA-Ald) along its backbone. Alternatively, polyethylene glycol dialdehyde (PEG-DiAld,
Mw 3400) was employed as the second component in place of HA-Ald. Simple mixing of
the respective components resulted in bulk hydrogels that were degraded rapidly in the
presence of hyaluronidase. On the other hand, in situ cross-linking within inverse
emulsion droplets generated microgels with improved stability and defined functionality.
These hydrogel microspheres are interesting in that they exhibit residual functional groups
on their surfaces which can be used as reactive handles for covalent conjugation of
therapeutic molecules. The presence of surface functional groups also allows for
subsequent cross-linking of the microgels with other reactive polymers, giving rise to
macroscopic hydrogels with tunable viscoelasticity. Mechanical measurements indicate
that these microgel networks exhibit similar viscoelastic responses as the natural vocal fold
lamina propria at phonation frequency range. In vitro cytotoxicity studies using vocal fold
fibroblasts indicate that microgels synthesized from HA-Hdz/HA-Ald are highly
biocompatible, whereas microgels derived from HA-Hdz/PEG-DiAld exhibit certain
adverse effects to the cultured cells at high concentration (≥ 2 mg/ml). These HA-based
microgel systems hold great promise for the treatment of vocal fold scarring, not just as an
inert filler material, but instead as smart entities that can repair focal defects, smooth the
vocal fold margin, and soften and dissolve scar tissue.
96
Oral Abstracts
A3 – Contributed Paper
MINIEMULSIONS FOR BIOMEDICAL APPLICATIONS
Anna Musyanovych, Katharina Landfester, University of Ulm, Department of
Organic Chemistry III / Macromolecular Chemistry, 11 Albert-Einstein-Allee,
Ulm 89081, Germany; and Volker Mailänder, Institute for Clinical Transfusion
Medicine and Immunogenetics Ulm, Department of
Transfusion Medicine, University of Ulm, 10 Helmholtzstr., Ulm 89081,
Germany; anna.musyanovych@uni-ulm.de
99
Polymeric particles in the sub-micron size range with advanced and controlled properties
have been synthesized by the miniemulsion process. Miniemulsions consist of liquid
nanodroplets in the size range of 50 to 500 nm and can be easily prepared by shearing the
system consisting of oil, water and a surfactant. The growth of the nanodroplets can be
effectively suppressed by using a strong hydrophobe and effective surfactant. The
hydrophobe acts as an osmotic agent which stabilizes the system against Ostwald ripening.
Such a system contains about 1018 droplets and each droplet behaves as an independent
reaction vessel that can be identified as a “nanoreactor”. Different types of reactions can be
performed inside the droplets or at their interface in order to design biologically interesting
materials according to the medical needs and application. For example, labeling of cells
with nanoparticles for in-vivo detection was performed by using fluorescent amino- or
carboxyl-functionalized polystyrene nanoparticles. The particles of 100-180 nm were
synthesized by miniemulsion copolymerization of styrene and a functional monomer in the
presence of a fluorescent dye. The cell uptake was visualized using fluorescent
microscopy. The presence of functional groups on the surface allows the covalent coupling
of biomolecules and used the obtained nanoparticles for bio-specific cell recognition.
Polymer nanocapsules with oil or aqueous core and various wall thicknesses were
successfully prepaid by performing the reactions at the interface of miniemulsion droplets.
By appropriately choosing the capsule wall material and reaction conditions,
biocompatible/biodegradable nanocapsules can be synthesized and used as the potential
carriers in drug delivery system. The miniemulsion technique was applied to prepare
“nanoreactors” and perform the multiplication of DNA molecule via polymerase chain
reaction (PCR) within these “nanoreactors”. When the droplets are in the size range
smaller than 300 nm it is possible to obtain a single molecule chemistry situation.
A3 – Invited Paper
TARGETING MONOCYTES BY NANO-PARTICULATED
FORMULATIONS AND VASCULAR HEALING
Gershon Golomb, School of Pharmacy, Faculty of Medicine, The Hebrew
University of Jerusalem, Jerusalem, Israel; golomb@md.huji.ac.il
100
Inflammation plays a key role in the progression of post-injury neointimal hyperplasia.
Local inflammatory activation occurs in a timely fashion following injury. We validated
the hypothesis that systemic and transient depletion of monocytes and macrophages
inhibits restenosis. Monocytes/macrophage depletion was achieved with a systemic
97
Oral Abstracts
injection of liposomes or polymeric nanoparticles (NP) containing bisphosphonates (BP)
formulated for effective phagocytosis. Following phagocytosis the vesicles discharge their
encapsulated drug, inactivating the cell with no effect on non-phagocytic cells. We
investigated the effect of different bisphosphonates (alendronate and clodronate), NP size
(0.1, 0.2, 0.4 and 0.8nm), and phospholipids and polymer type on the formulation and
bioactivity properties. The pharmacokinetics and pharmacodynamics have been evaluated
by utilizing 67Ga encapsulated in liposomes. The bioactivity of the nanoparticulated dosage
forms was assessed in cell cultures of RAW 264 macrophages and primary SMC of rat,
rabbit and human. Inhibition of blood monocytes was measured by flow cytometry (FACS)
following IV injection of different formulations, and in vivo therapeutic efficacy was
studied in rat and rabbit restenosis models. Monocytes count was reduced by 70%, 24-48
hrs. after a single injection of alendronate liposomal formulation, at a dose 10-fold lower
than that of clodronate. Monocyte blood levels returned to basal values after 7 days. A
significant reduction of stenosis (>70%) was achieved in both rat and
hypercholesterolemic-rabbit models of restenosis, without side effects. The NP dispose
mainly to the liver and spleen with high uptake in the injured artery transported by
circulating monocytes. It can be concluded that macrophage depletion by NP encapsulated
BP is a promising therapeutic tool against restenosis after angioplasty.
A3 – Invited Paper
OCULAR DRUG DELIVEY USING LIPID, POLYMER AND
SUSPENSION FORMULATIONS
Ron Boch, Lina Hong, Yuan Huang, Ruihong Li, Philippe Margaron,
Jasbinder Sanghera, Luis Sojo ; QLT Inc. 887 Great Northern Way,
Vancouver, British Columbia, Canada V5T 4T5; rboch@qltinc.com
101
The treatment of eye diseases such as age-related macular degeneration (AMD)
necessitates drug delivery to the back of the eye. The in-vivo delivery of ocular drugs is
achievable by the systemic route of administration or by directly injecting compounds into
the eye. Drug candidates were screened in cellular screening assays. Poorly water soluble
small molecule compounds were formulated for intravenous injection or for local
administration to deliver test compounds to the back of the eye. Aqueous formulation
strategies for liquid solutions and suspensions included a variety of approaches to enhance,
or sustain the delivery to improve efficacy. One class of drugs, derived from Visudyne®
(used in photodynamic therapy of certain eye diseases) called benzoporphyrin derivatives
were administered intravenously. These drug formulations were assessed in vivo for
systemic delivery. Alternatively, suspension formulations of poorly soluble small
molecule angiogenesis inhibitors were administered locally into the eyes of anaesthetized
animals. Delivery to the back of the eye was assessed by extracting the ocular tissues for
active substance. Aqueous formulation strategies for poorly soluble candidates included
the use of surfactants, lipids, polymers and cyclodextrins. Following intravenous
administration into animals, the systemic delivery was found to be compound and
formulation dependent. Suspension formulations that were locally injected into the eye
achieved high levels of active substance in ocular tissue. Local and intravenous routes of
administration effectively delivered poorly soluble test substances to the back of the eye.
98
Oral Abstracts
A3 – Invited Paper
IMAGING CELL SURFACE RECEPTORS WITH LIGAND CONJUGATED
NANOCRYSTALS
Sandra J. Rosenthal, Department of Chemistry, Vanderbilt University,
Nashville TN 37235, USA; sjr@femto.cas.vanderbilt.edu
102
The simultaneous localization of several different proteins in situ is has been limited by the
wide emission spectra and low photostabilities of fluorescent dyes traditionally used to
study cell surface receptors, ion channels, and transporters. It has been demonstrated that
core/shell semiconductor nanocrystals can overcome these limitations. We have developed
small molecule, peptide, and antibody nanoconjugates for targeting cell surface receptors.
The structure of the core/shell nanocrystals has been determined with exquisite resolution
by atomic number constrast scanning transmission electron microscopy. The biological
activity of the nanoconjugates is determined by competitive uptake assay. Imaging and
detection applications in neuroscience and immunology will be discussed.
A3 – Contributed Paper
ORAL INSULIN DELIVERY WITH BIODEGRADABLE AND
BIOCOMPATIBLE NANOCAPSULES
Zhengmao Li, Robert Gyurik, Bentley Pharmaceuticals, Inc., 2 Holland Way,
Exeter, NH 03833, USA; and Jerome Claverie, Materials Science Program,
University of New Hampshire, Durham, NH 03824, USA;
zli@bentleypharm.com
103
In protein and peptide delivery, researchers and consumers are always seeking viable
alternatives to painful and bothersome injections. Among pulmonary, intranasal,
transdermal and other options, oral delivery is the most preferred route and is also the most
challenging route. In order to protect the hydrophilic therapeutic proteins and peptides
from degradation in the intestine via oral delivery, we have developed a Nanocaplet™
delivery system, using poly(glutamic acid)-poly(lactic acid)-poly(ethylene glycol) triblock
copolymers via self-assembly. The size of a Nanocaplet™ is as small as 100 nm. Due to the
biodegradable and biocompatible nature of the copolymer, the safety concerns over
nanotechnology can be resolved by our delivery system. Human insulin is used as a model
protein. The pharmacokinetic animal (rat) study results show that insulin can be
successfully delivered in Nanocaplet™ form through the intestine. The fact that the human
insulin concentration in the blood peaks around 90 minutes after the administration,
indicats protection and degradation of the Nanocaplet™ after uptaken by the epithelial
cells in the intestine.
K1 –Keynote Paper
THE NANOSCALE IN INHALATION DELIVERY
Philippe G. Rogueda, AstraZeneca R&D Charnwood, Bakewell Road,
Loughborough, LE11 2HD, UK; philippe.rogueda@astrazeneca.com
104
Inhalation delivery covers 4 formulation platforms: dry powder inhalers (DPIs), pressure
99
Oral Abstracts
metered dose inhalers (pMDIs), nebulisers and nasal devices. There are currently no
products on the market claiming the use of nanoparticles or nanodroplets for inhalation
delivery, although some may unknowingly benefit from their presence. There is however a
range of patents and delivery platforms available claiming the use of the nanoscale.
Deposition of particles/droplets in the lung is normally associated with sizes between 1-5
μm. Particles below 100 nm are also known to reach the deep lungs, and these open
numerous possibility for nanoparticle inhalation delivery. There have been some concerns
about the toxicity of nanoparticles in the lungs, but these must be seen in the context of the
chemical entity used. Most nebulisers are formulated as aqueous solutions, therefore
nanodroplets production is a matter of fact, and can be achieved through adequate
hardware. DPIs (dry powder inhalers) are yet to fully exploit nanoparticle delivery. The
size distribution of a pMDI aerosol cloud is bimodal by nature, with 2 peaks: at 600 nm and
2 μm. Therefore a solution pMDI will deliver nanoparticles to the lungs. For suspension
pMDIs, the delivery of nanoparticles necessitates the availability of dry, stable, individual
nanoparticles. These are not available in commercially viable quantities yet. If it is
assumed that nanoparticles can be made available, their fate in suspension will need to be
considered, in particular their stabilisation. In addition, their fate in the aerosol droplets
will need to be studied, as theories predict that agglomeration will occur, leading to the
delivery of micron sized particles.
K1 – Invited Paper
PARTICULATE SYSTEMS FOR PULMONARY DRUG DELIVERY:
SAFETY, SUSTAINED RELEASE, AND EFFICACY
Uday B. Kompella and Devender Dhanda. College of Pharmacy, University of
Nebraska Medical Center, Omaha, NE 68198-5840; ukompell@unmc.edu
105
Ou purpose in this work was to determine whether intratracheally administered large
porous microparticles are safe and sustain celecoxib delivery in mice and to further assess
their effectiveness in a mouse model for lung tumors. Celecoxib-PLGA (75/25) large
porous microparticles were prepared using a modified solvent evaporation method
followed by supercritical fluid processing. The pulmonary safety of celecoxib and PLGA
particles (conventional and large porous) with and without celecoxib was assessed by
determining lactate dehydrogenase (LDH) levels, total protein levels, and total and
differential cell counts in the bronchoalveolar lavage fluid (BAL) and soluble collagen
levels in the lung tissue of A/J mice 21 days following intratracheal administration. Lung
sections were stained with hematoxylin and eosin (H&E) and Masson’s Trichrome stain
for gross histological evaluations to assess the inflammatory and/or fibrotic response. To
assess sustained drug delivery, particle formulations were administered in normal A/J mice
and the plasma, BAL, and lung tissues were isolated on day 21 and the drug levels were
quantified using an LC-MS assay. For efficacy studies, female A/J mice were administered
2 mg B[a]P orally in 0.2 ml of cottonseed oil on days 1, 4, and 7. Dry powder formulations
of celecoxib, and PLGA microparticles with or without celecoxib (~90 µg of celecoxib)
were administered intratracheally using a dry powder insufflator one week after the last
dose of B[a]P. The animals were sacrificed on day 14 post-administration and
prostaglandin E2 (PGE2) and vascular endothelial growth factor (VEGF) levels were
100
Oral Abstracts
determined in the BAL. There was no significant hyperplasia, granulomatous tissue, and
collagen deposition in the lung in the formulation treated groups. In addition, the measures
of cellular injury (lactate dehydrogenase levels), vascular leakage (total protein levels), and
pulmonary fibrosis (soluble lung collagen levels) were not significantly different between
the untreated and the formulation treated groups. The drug levels at the end of 21 days in
the lung tissue for large porous celecoxib-PLGA microparticles were 5- and 50-fold
higher, when compared to conventional celecoxib-PLGA microparticles and celecoxib
powder, respectively. The drug levels were 15- and 96- fold higher in the BAL for large
porous microparticles when compared to conventional particles and celecoxib powder,
respectively. B[a]P treatment significantly increased the PGE2 and VEGF levels and
single doses of dry powder formulations of conventional and large porous
celecoxib-PLGA microparticles significantly reduced these elevations. We thereby can
conclude that large porous celecoxib-PLGA microparticles are safe and do not cause any
significant lung inflammation, cellular injury, or pulmonary fibrosis. These particles better
sustain pulmonary drug delivery compared to conventional microparticles or drug powder,
and reduce B[a]P induced elevations in PGE2 and VEGF levels in a lung tumor model.
K1 – Contributed Paper
AN INGREDIENT-SPECIFIC METHOD FOR PARTICLE SIZE
CHARACTERIZATION OF CORTICOSTEROID NASAL SPRAYS
Oksana Klueva, Matthew P. Nelson, Patrick J. Treado, and Amy M.
Waligorski, ChemImage Corporation, 7301 Penn Ave., Pittsburgh PA 15208,
USA; and Changning Guo, William H. Doub, John A. Spencer, Food and Drug
Administration, St. Louis, MO, 63101 USA; kluevao@chemimage.com
106
FDA Draft Guidance on bioavailability and bioequivalency studies for nasal aerosols and
sprays (2003) advocates in vitro methods for establishing bioequivalency for solution
formulations of locally acting nasal sprays and aerosols, based on the assumption that in
vitro studies are more sensitive indicators of drug delivery to nasal sites of action compared
to clinical studies. Particle size is an important physico-chemical property of nasal sprays
as it influences bioavailability, delivery rate, stability and, ultimately, safety and efficacy
of the inhaled drug. Currently there is no validated in vitro method to characterize API
particle size distribution (PSD) in formulated aqueous nasal spray suspensions.
Availability of such a method would provide pharmaceutical scientists with a reliable
assessment of API-specific PSD of drug substances in finished aqueous suspension nasal
spray products. Raman chemical imaging (RCI) technology is being investigated as a
methodology for ingredient-specific PSD determination for several corticosteroid aqueous
suspensions. A Raman spectral library has been developed for the active and inactive
compounds in the several corticosteroid formulations (Rhinocort AQ™, Flonase™,
Beconase AQ™, Nasonex AQ™). Raman and optical imaging techniques have been
applied over hundreds of particles fields of view to characterize PSD of active ingredients.
Raman imaging obtained from corticosteroid API in 1600-1700 cm-1 spectral range
allowed ready distinction between the drug and excipient. The Raman images can be used
to calculate particle size of those active pharmaceutical ingredients (API) independent of
excipients of the mixture as well as adhered to excipient particles. From these and on-going
101
Oral Abstracts
studies, RCI has been able to differentiate active ingredient within complex aqueous nasal
spray samples and allow measurement of the PSD of active drug components. In
summary, RCI technique shows promise as a method for characterizing particle size of
corticosteroids in aqueous suspension nasal sprays. The current state of validation of RCI
for particle analysis will be presented.
K1 – Contributed Paper
A STUDY OF LIQUID PROPERTIES AND DROPLET SIZE
DISTRIBUTIONS OF SOME COMMON NASAL DECONGESTANT
SPRAY FORMULATIONS
Mark Bumiller, Henrik Krarup and Chuck Rohn, Malvern Instruments, Inc.,
10 Southville Road, Southboro, MA 01772; mark.bumiller@malvernusa.com
107
Laser diffraction is recommended for in vitro testing of droplet size distribution
characteristics in bioequivalence and bioavailability studies of nasal sprays and nasal
aerosols. The droplet size distribution obtained from the nasal pump is a function of factors
ranging from actuation characteristics, pump design to the rheological properties of the
formulation liquid. In particular microcrystalline cellulose and carboxymethylcellulose
(CMC) is used as a viscosity modifier to enhance the residence time in the nasal cavity.
This study investigates the viscoelasticity of two common nasal decongestants and
compares rheological properties to the droplet size distribution obtained from laser
diffraction. Results indicate that the long relaxation time described by the low frequency
storage modulus G’ that relates to the extensional rheological behavior of the material.
Formulation A has higher G’ than formulation B, at lower frequencies, indicating that
formulation A is more elastic and thus more capable of forming larger droplets.
K1 – Invited Paper
NEW POLYMER ENABLES ZERO-ORDER RELEASE OF DRUGS
James R. Benson, Nai-Hong Li, William Landgraf, Polygenetics, Inc., P.O.
Box 33115, Los Gatos, CA 95031, J-Benson@polygenetics.com
108
Scientists at Polygenetics, Inc. have developed a highly porous polymer material
(Cavilink™) that can be used to contain drugs, and release those drugs following near
zero-order kinetics. The polymers can have up to 90% porosity so that drug-polymer
combinations are 90% pure. The zero-order release feature is due to the unique, patented
polymer morphology and is independent of drug composition. Constant blood levels can be
maintained for twenty-four hours, making these polymers ideal for oral drug delivery
applications. Cavilink™ polymers are not metabolized and pass through the GI tract
unchanged. These polymers are particularly suited for medical problems in which constant
blood levels are particularly important, such as pain management, cardiovascular
intervention, anti-inflammatory and certain antimicrobial treatments. Cavilink™ polymers
can also be used effectively in taste masking applications.
102
Oral Abstracts
K1 – Invited Paper
ADVANCES IS LIQUID AEROSOL DELIVERY SYSTEMS
Jeffrey Schuster and Jim Blanchard, Aradigm Corporation, 3929 Point Eden
Way, Hayward, CA, 94545, USA; SchusterJ@Aradigm.com
109
Aerosol drug delivery presents a significant opportunity for topical lung treatment and
non-invasive delivery of systemically active compounds. Because the lung is an anatomic
portal of entry to the systemic circulation, there is the possibility of much higher efficiency
and more rapid onset as compared to other non-invasive methodologies such as
trans-dermal or nasal. At Aradigm corporation, we have developed a highly efficient
technology for the delivery of aqueous aerosols via the lung, the AERx® system. The
AERx system generates a fine particle aerosol from a liquid formulation which is packaged
in a unit dose container with an integrated single use disposable nozzle. An all electronic
version, with features such as dose titration and compliance monitoring, is in Phase III
clinical trials with insulin. We have developed a smaller and more cost effective platform
based on this technology, AERx Essence™. This system is all mechanical, and includes
features that ensure proper inhalation rate and proper coordination of delivery with
inhalation. Results of a Gamma-scintigraphic study utilizing SPECT, and a user study,
will be presented. Additionally, there are two new inhaler technologies under development
at Aradigm. One is a single use disposable version of our AERx technology, AERx
Ease™. Because AERx Ease utilizes components from AERx Essence and our Intraject®
needle-free injector platform that are scaled up for high volume manufacture, development
times and cost should be minimal. The second technology in development is our
Pulmoshield™ platform, based on an aerosolization technology licensed from the
University of Seville. The Pulmoshield technology will deliver very high density aerosols,
minimizing the long treatment times that are associated with presently available nebulizers.
K1 – Invited Paper
EMBRACING PARTICLE ENGINEERING FOR INHALATION DRUG
PRODUCTS
Robert Cook, Thomas Armer, MAP Pharmaceuticals, Inc. 2400 Bayshore
Parkway, Mountain View, CA 94043, USA; rcook@mappharma.com
110
Particle engineering offers potential to enhance inhaled product performance and provide
differentiated patient benefits; e.g. formulation of drugs that could otherwise not be
delivered by inhalation, more consistent dosing, rapid onset of therapeutic action and
dosage reduction. Budesonide is a corticosteroid indicated for bronchial asthma. For
patients unable to use pressurised metered dose inhalers (pMDIs) or dry powder
formulations (e.g. young children), an aqueous suspension of micronised budesonide
(nebuliser delivery) is a clinical alternative - delivery of which is typically inefficient. A
novel, particle engineered submicron aqueous dispersion of budesonide was formulated for
improved performance. At equivalent clinical dose (1 mg) and strength (0.5 mg/mL), the
submicron formulation delivered twice the fine particle dose (FPD, mass deposited in an
Andersen Cascade Impactor <4.7 μm): 145±8 mcg compared to 69±6 mcg for the
existing commercial budesonide preparation (Pulmicort Respules, AstraZeneca).
103
Oral Abstracts
Therefore, potential for reduced corticosteroid doses and faster delivery times may exist
for this engineered product. Dihydroergotamine mesylate (DHE) is used for effective
migraine treatment, by IV injection or nasal delivery. DHE was processed using
supercritical fluid technology into highly respirable crystals (<3 μm). Suspension of these
crystals in hydrofluoroalkane propellant in pMDI canisters (500 mcg/actuation) yielded a
FPD of 162±5 mcg. Combining this formulation with a next generation inhaler
(Tempo™), with advanced aerosol plume control and breath synchronous delivery,
elevated FPD to 220±15 mcg, and halved throat deposition (80.6 vs. 156.5 mcg). The
respirable dose achieved in humans resulted in 250 mcg/actuation delivered to the plasma.
Plasma profiles of this inhaled DHE formulation, from Tempo, closely matched IV
administration, reaching faster peak concentrations than nasal preparations (10 vs. 45 min)
thus offering injection-free potential for rapid migraine relief. These two products, under
development, provide noteworthy examples of where particle engineering can significantly
benefit both local and systemic inhalation drug therapy.
K1 – Invited Paper
DESIGN AND PRODUCTION OF ULTRAFINE ACTIVE
PHARMACEUTICAL INGREDIENTS UNDER HIGH GRAVITY
ENVIRONMENT
Jimmy Yun1, Jian-Feng Chen1,2, Hak-Kim Chan3, William Glover1,
1
Nanomaterials Technology, Singapore; 2Sin-China Nanotechnology Center,
Beijing University of Chemical Technology, Beijing, China; 3Faculty of
Pharmacy, University of Sydney, Australia; jimmy.yun@nanomt.com
111
Currently there is an increasing trend in pharmaceutical aerosol development to investigate
highly dispersive formualtions to improve drug delivery to the lungs. The reality of these
formulations may be realised using engineered nanoparticles. There is a variety of
methods of preparation, however the production scalability and cost associated with these
processes represent significant constraints for these technologies to conquouer. High
gravity precipitation has the potentially to overcome these obstacles based on its simplistic
design around crystalisation kinetics, nucleation events occur rapidly in a turbelent zone
and are seperated from the crystal growth region of the process. This in turn can lead to the
production of extremely small particles (10 to 1000nm). A feasibility study was performed
on a common inhalation drug to assess the suitability of high gravity precipitation for
producing active ingredients for aerosol drug delivery. Two separate precipitation
methods i) a standard antisolvent precipitation and ii) a reactive precipitation were
designed around the high gravity precipitation platform. Optermization trials were carried
out by varying solvent/antisolvent ratios, concetrations of drug and rates of addition. The
purpose of the optermization trials was to reduce the primiary particle size below 500nm x
1µm. Suspensions of the precipitated particles were spray dried in order to evaporate
excess solvent and form dry powders. The morphology of the powders consisted of
uniform needle shaped nanoparticles which appear moderately agglomerated. X-ray
diffraction analysis indicated that powders produced from both methods were crystaline in
nature. The in vitro aerosol dispersion results (FPFloaded under 5µm) for nanonised
salbutamol sulphate was 52% and 83% for the antisolvent and reactive precipitations
104
Oral Abstracts
respectively. This is considerably better than the commercially available micronized raw
material with 16%. In conclusion, nanonising active pharmaceutical ingredients using
high gravity precipitation has the potenital to further improve physical characteristics of
pharmaceutical aerosols which may lead to increased delivery performances of drug
compounds.
L1 – Keynote Paper
NEW POLYMER-LIPID HYBRID NANOPARTICLES FOR ENHANCED
ANTICANCER DRUG DELIVERY
Xiao Yu Wu, H.L. Wong, R. Bendayan, Leslie Dan Faculty of Pharmacy,
University of Toronto, Toronto, Ontario, Canada M5S 2S2; A.M. Rauth,
Ontario Cancer Institute, Toronto, Ontario, Canada M5G 2M9;
xywu@phm.utoronto.ca
112
New polymer-lipid hybrid nanoparticles (PLN) were developed for the first time for
enhanced delivery of water-soluble, ionic anticancer drugs and chemosensitizing agents to
treat multidrug resistant (MDR) cancer. PLN containing drug-polymer complex and lipid
were produced after sonication and cooling. The size and morphology of the particles were
characterized by photon correlation spectroscopy and transmission electron microscopy.
The drug loading and release kinetics were measured by spectrophotometry. A trypan blue
exclusion assay and a clonogenic assay were carried out on a P-glycoprotein (P-gp)
over-expressing human breast cancer cell line (MDA435/LCC/MDR1) to determine the
effects of the formulation on cell survival. The influence of the formulations on the rates of
cellular uptake and efflux, and cellular distribution of doxorubicin (Dox) was also studied.
Dox-PLN with 60-80% drug encapsulation efficiency and particle diameters of 80-350 nm
were obtained. Drug release was faster in the first two hours followed by slower release
which lasted over 16-70 hours. Neither the polymer alone or blank PLN altered membrane
permeability. In the clonogenic assay, Dox-PLN resulted in nearly an additional log kill on
MDA435/LCC6/MDR1 cells, while did not lead to different activity against wild-type
cells as compared to the conventional Dox treatment. Prolonged accumulation of
Dox-PLN in the MDR cell line was observed. The PLN formulation containing both Dox
and GG918, a Pgp inhibitor, was more effective against Pgp-overexpressing cancer cells
than the two drugs in solution form or separate PLN form. This result suggests that it may
be advantageous to simultaneously deliver the drug combination in a single carrier system.
The present study indicates that Dox-PLN possess significant MDR reversal activity. The
elevated activity is likely a result of the intracellular accumulation of the Dox-PLN, which
are difficult to remove by the drug efflux transport mechanism and may serve as extended
intracellular sources of Dox.
L1 – Invited Paper
A VERSATILE TUMOR TARGETING NANOADELIVERY PLATFORM
FOR CANCER DIAGNOSIS AND THERAPY
Esther Chang and Kathleen F. Pirollo, Georgetown University Medical
113
105
Oral Abstracts
Center, 3970 Reservoir Rd NW, TRB/E420, Washington, DC 20057-1469,
USA; pirollok@georgetown.edu
Many issues need to be addressed before the promise of tumor-targeting diagnosis and
therapy for cancer can be realized. Foremost among these is the efficient and selective
delivery of diagnostic and/or therapeutic molecules to the site(s) in the body where the
target tumor cells reside. Of particular relevance to cancer is the ability to target cells that
have metastasized from the site of the primary tumor to distant sites in the body. Our
laboratory has developed a platform nanotechnology comprising a cationic liposomal
nanocomplex bearing molecules that home to the surface of tumor cells. When
systemically administered, this tumor targeting nanocomplex can efficiently and
selectively deliver not only nucleic acid-based therapeutics, but also diagnostic contrast
agents and small molecules to primary tumors and metastases in animal models of a variety
of human cancers. The nanodelivery of imaging agents results in a significant
improvement in the sensitivity and resolution in detecting metastatic lesions. Moreover,
the various nucleic acid-based therapeutics have been shown to dramatically synergize
with conventional radio- and chemotherapies. This approach is now entering clinical trials.
L1 – Contributed Paper
DNA MESOSPHERES AS DRUG DELIVERY VEHICLES FOR
LOCALIZED CANCER CHEMOTHERAPY
Iris V. Enriquez1,3, Eugene P. Goldberg1,2,3
1
Department of Materials Science & Engineering, 2Department of Biomedical
Engineering, 3Biomaterials Center, University of Florida, PO Box116400,
Gainesville, FL 32611-6400; ive@ufl.edu, egoldberg@pol.net
114
There is a growing need to find alternative delivery methods for cytotoxic
chemotherapeutic agents. Traditional systemic chemotherapy is often limited in
effectiveness and may severely impact the quality of life for many patients. Recent
research has shown that intratumoral therapy may be a useful alternative to conventional
systemic chemotherapy. The potential benefits of intratumoral therapy are localized
delivery of an extraordinary drug dose to the tumor site, greatly reduced systemic toxicity,
and the opportunity to prolong the local effectiveness of the drugs. Previous research in our
lab with various protein nano-meso-microspheres in a variety of animal cancer models has
been promising and suggests unique opportunities for the use of deoxyribonucleic acid
(DNA) as a mesosphere drug carrier. The research reported here was therefore devoted to
the synthesis and properties of new DNA mesospheres (DNA/MS). DNA has been shown
to complex with many cancer drugs and Trouet investigated the systemic delivery of a
complex with daunorubicin. It was observed that the DNA-drug complex had reduced
cardiotoxicity and provided a longer blood half life. The therapeutic value of the DNA
complex was also comparable to that of free drug. These studies further suggested to us
that crosslinked but biodegradable DNA mesosphere compositions, which had not been
previously reported, might have interesting and useful drug delivery properties. DNA/MS
were synthesized using a steric stabilization process developed in our lab. In brief, the
process involved dispersing an aqueous DNA solution in an organic phase solution
106
Oral Abstracts
composed of 5% cellulose acetate butyrate in 1,2-dichloroethane. After vigorous mixing,
the resulting MS suspension was crosslinked in a novel fashion, i.e. with chromium (Cr3+)
or gadolinium (Gd3+) ions via the phosphate groups of the DNA molecule. After
crosslinking, the DNA/MS were purified by acetone wash and dried at room temperature.
Resulting DNA/MS were characterized for particle size, morphology, and elemental
composition. Uniform spherical particles were readily synthesized with yields of >70%
and with dry vs. hydrated diameters of 4um vs. 13um. Drug loading studies with various
cancer drugs, using in situ and post-loading methods, are in progress.
L1 – Invited Paper
LIGAND-MEDIATED TARGETING OF NANOPARTICLES AND LOW
MOLECULAR WEIGHT DRUGS TO CANCER CELLS AND
INFLAMMATORY IMMUNE CELLS
Philip S. Low, Department of Chemistry, 560 Oval Drive, Purdue University,
West Lafayette, IN 47907, USA; plow@purdue.edu
115
We have been developing methods to target drugs specifically to pathologic cells, thereby
avoiding the collateral toxicity associated with drug uptake by healthy cells. In the case of
cancer, we have exploited the strong upregulation of the folate receptor on malignant cells
to target: i) protein toxins, ii) chemotherapeutic agents, iii) gene therapy vectors, iv)
oligonucleotides, v) radioimaging agents, vi) nanoparticles, vii) liposomes with entrapped
drugs, viii) radiotherapeutic agents, ix) immunotherapeutic agents, and x) enzyme
constructs for prodrug therapy to tumor tissue by linking the various agents to the vitamin
folic acid. Current clinical trials of folate-linked drugs demonstrate that the
folate-targeting strategy holds great promise for significantly improving the tumor
specificity of therapeutic reagents. Folate-linked drugs must obviously extravasate and
penetrate the tumor tissue before they can bind to FR-expressing cancer cells.
Consequently, size, shape, and water-solubility influence a folate conjugate’s tumor
targeting ability. Data showing the real time penetration, binding and internalization of
various fluorescent folate conjugates by tumor cells in live mice, as monitored by
multiphoton intravital microscopy, will be presented to illustrate the impact that particle
size has on its penetration into solid tumors. We are also developing drug targeting
strategies for the imaging and therapy of rheumatoid arthritis, Crohn’s disease,
atherosclerosis, lupus, glomerulonephritis, atherosclerosis, and multiple sclerosis.
Methods associated with these technologies will also be discussed.
L1 – Invited Paper
SINGLE WALL CARBON NANOTUBE NANOBOMB AGENTS FOR
CANCER THERAPEUTICS
Balaji Panchapakesan, Department of Electrical and Computer Engineering,
University of Delaware, Newark, DE 19716; baloo@ece.udel.edu
116
Although there have been outstanding advances in fundmental cancer biology, these have
not translated into comparable advances in the clinic. Inadequacies in the ability to
107
Oral Abstracts
administer therapeutic agents with high selectivity and with minimum collateral damage
have largely accounted for such discrepancies in cancer therapeutics. Furthermore it is
most astonishing to recognize that only 1 to 10 parts per 100,000 of intravenously injected
monoclonal antibodies reach their targets in vivo. Keeping these in mind, in this paper, we
report the applications of single wall carbon nanotubes as potent threpautic nanobomb
agents for killing breast cancer cells. By adsorbing water molecules in loosely packed
nanotubes that are adsorbed on top of cell clusters, potent nanobombs were created when
nanotubes were exposed to 808 nm laser light at light intensities between 50-200 mW/cm2
that completely destroyed the cells that were in contact with the nanotubes. Conversion of
optical to thermal energy and subsequent thermal energy confinement in nanotubes caused
such explosions in water and saline solutions. Co-localized nanobombs killed human
BT474 breast cancer cells in physiological phosphate buffered saline solution. Cells that
were treated with nanobombs exploded into fragments while the surrounding cells that
were not treated with the nanobombs were healthy and viable showing the selective nature
of this cell killing technique. Nanobombs coated with Her2 specific antibodies were highly
selective in killing BT474 cancer cells (overexpress Her2) compared to non-specific
antibodies paving the way for immunotargeted nanobombs for cancer therapeutics.
Nanobombs can find wide variety of use in cancer therapeutics, immunotargeting, drug
delivery and minimally invasive surgical applications.
L1 – Invited Paper
FOLATE RECEPTOR-TARGETED LIPOSOMES AND NANOPARTICLES
FOR CANCER THERAPY
Robert J. Lee, Division of Pharmaceutics, College of Pharmacy, NCI
Comprehensive Cancer Center, NSF Nanoscale Science and Engineering
Center, The Ohio State University, Columbus, OH 43210, lee.1339@osu.edu
117
Targeted delivery through malignancy-associated cellular markers is a promising strategy
for cancer therapy. Folate receptor (FR) is a cell surface receptor selectively amplified in a
significant fraction of human neoplasms. Folate binds to FR with high affinity, displays
high specificity and enters cancer cells through receptor-mediated endocytosis. FR,
therefore, represents a very attractive selective target for cancer-specific delivery of
therapeutic agents. FR-targeted liposomes have been constructed through incorporation of
a lipophilic derivative of folate. FR-targeted liposomes have been loaded with a variety of
bioactive reagents. It has been evaluated for the targeted delivery of anticancer agents to
cancer cells and was shown to be efficiently internalized and selectively cytotoxic to FR
positive cells. In addition, FR-targeted liposomal doxorubicin has been shown to
overcome Pgp-mediated drug resistance in vitro and to have superior antitumor activity to
non-targeted control liposomes in several preclinical murine tumor models. Furthermore,
strategies have been developed to selectively up-regulate FR-beta expression in human
acute myelogenous leukemia and FR-alpha expression in solid tumors, which might
further enhance the translational potential of this targeting strategy. FR-targeted liposomal
drug delivery thus represents a particularly attractive strategy for future development.
108
Oral Abstracts
D3 - Keynote Paper
SUPERPARAMAGNETIC IRON OXIDE NANOPARTICLES AS A DRUG
DELIVERY SYSTEM FOR IN VIVO APPLICATION IN THE JOINT
Brigitte von Rechenberg, Musculoskeletal Research Unit, Equine Hospital,
Vetsuisse Faculty Zurich, University of Zurich, Switzerland;
brigitte.vonrechenberg@forschungpferd.ch
118
Joint diseases are one of the most common orthopedic problems in daily patient care. They
may be either related to the rheumatoid complex including polyarthritis or to degenerative
processes caused through traumatic lesions and/or mechanical overload. Degenerative
joint diseases are becoming more important as a consequence to a society, where the age
expectation has increased considerably, sports play a significant role in daily life of young
and middle aged persons and where overweight has become the rule rather than the
exception. Although much research has been devoted to understand or inhibit chronic
inflammation and mechanisms leading to osteoarthritis, the “magic bullet” or drug has not
been found yet, let alone a drug that would be locally effective while not having major
systemic side effects (kidney disease, gastric ulceration, stroke, heart disease, etc.). Drugs
that are given systemically and slow down the process of osteoarthritis are usually directed
towards inhibiting joint inflammation (eg.cox-2 inhibitors), resp. down regulate
degradation of the cartilage matrix through local enzymes, such as matrix
metalloproteinases (MMPs). When given systemically, it may prove difficult to achieve
effective local concentrations of the drugs within the joint because of chronic indurations
and fibrosis of the joint capsule and ligaments. In the other hand, if drugs are given locally
through intraarticular injections, the maintenance of effective concentrations may also be
impossible, since drugs may be filtered and transported away from the joint within a very
short time period (ca. 1hour) and before full action can be reached. Superparamagnetic iron
oxide nanoparticles (SPION) seem be a very attractive drug delivery system to overcome
these problems, since they can be injected intraarticularly and maintained at the location by
means of an external magnetic field while protracted release of drugs could take place.
Therefore, our collaborative research efforts have focused on the use of SPIONs as drug
delivery system for drugs, or as non-viral gene transfection system for plasmids (DNA).
Since no previous studies about the use of SPIONs within a joint were available, our work
concentrated first on in vitro work with primary cell lines of synoviocytes (cells lining the
joint capsule), where issues as particle uptake, dosage and toxicity were addressed. For all
our work, iron oxide particles with a core between 6-10nm were used that were either
coated with polyvinyl alcohol alone (PVA) or polyvinyl alcohol /vinyl amine copolymer
functionalized with Cy3.5 or Texas Red fluorescence dye. For gene transfection the same
type of SPIONs were used but coated with Polyethyleneimide (PEI) and functionalized
with plasmids encoding green fluorescent protein (GFP). Animal experiments were
conducted in sheep, where functionalized SPONs were injected intraarticularly (i.a) either
into the stifle or the radiocarpal joints. Immediately after SPION application external
magnets were locally fixed directly at the joint and kept in place for 12 hours in case of
plain PVA, or PVA-NH3-Cy3.5 coated SPIONs. With PEI-coated and with GFP-plasmid
functionalized particles a static magnet was first applied before a pulsating magnet was
applied for 5 minutes, after which the static magnet was reapplied and kept there for 12
hours. Animals were sacrificed at 24, 72 and 120 hours after injection, and after
109
Oral Abstracts
macroscopic assessment of the joints, tissue was harvested for histology. Apart from
routine HE sections special staining for detection of SPIONs within the tissue were applied
(Prussian Blue (PB), Turnbulls (TB)). Confocal microscopy was used for the detection of
the fluorescent dyes or GFP synthesis. Immunhistochemistry with antibodies against GFP
were additionally used for the gene transfection experiments. To follow the systemic
elimination of SPIONs samples of all organs except the brain were collected and
investigated with PB or TB stainings.Plain PVA-SPIONs were well biocompatible and
taken up by the synovial membrane within 24 hours. They were detectable for 120 h at
which time they had already penetrated into the deeper layers of the joint capsule. The
same was true for PVA-NH3-Cy3.5 SPIONs, although a mild inflammation was noticed at
72 h after injection. The Cy3.5 fluorescence occurred parallel to the particle uptake within
the synovial membrane. Systemic elimination of SPIONs could be followed and occurred
via the local lymphnodes into the systemic vascular system, where the particles were
filtered through the glomerular system of the kidney, were reabsorbed in the proximal
tubuli and were then captured in the reticuloendothelial system (RES) of the spleen and
liver. Cy3.5 fluorescence was noted only in the joint capsule, faintly also in the local lymph
nodes but not in the other organs. The PEI-coated and with GFP-plasmid functionalized
SPIONs also caused a moderate joint irritation already at 24h. Particle agglomeration was
noticed within the synovial fluid. GFP expression could not be found within the synovial
membrane, but in few cells of the local lymph nodes by means of immunohistochemistry.
Aggregation of the SPIONs seemed to elicited by the synovial fluid, and there, was
attributed to the negative charge of the proteoglycans and hyaluronic acid. In summary we
concluded that drug delivery with PVA-coated particles could be confirmed using Cy3.5 as
proof of principle, gene transfection of synoviocytes in vivo was not possible by means of
PEI-coated SPIONs. Future research will focus on drug delivery of anti-inflammatory
drugs for acute and chronic joint inflammations by usingf PVA-coated SPIONs. For gene
transfection by means of SPIONs new coatings and methods of plasmid functionalization
will be investigated.
D3 – Invited Paper
GENERALIZED AND LARGE-SCALE SYNTHESIS OF MONODISPERSE
NANOCRYSTALS OF FERRITES AND OXIDES AND THEIR
APPLICATIONS AS MRI CONTRAST AGENTS AND IN DRUG
DELIVERY
Taeghwan Hyeon, Jongnam Park, Kwangjin An, and Hyon Bin Na, National
Creative Research Initiative Center for Oxide Nanocrystalline Materials and
School of Chemical and Biological Engineering, Seoul National University,
Seoul 151-744, South Korea, thyeon@snu.ac.kr
119
We developed a new generalized synthetic procedure to produce monodisperse ferrite
nanocrystals without a size selection process. Highly-crystalline and monodisperse
nanocrystals were synthesized from the thermal decomposition of metal-surfactant
complexes. We synthesized monodisperse spherical nanocrystals of metals (Fe, and Ni),
and metal oxides (γ-Fe2O3, Fe3O4, CoFe2O4, MnFe2O4, NiO, and MnO). We report the
110
Oral Abstracts
ultra-large-scale synthesis of monodisperse ferrite nanocrystals by the thermolysis of
metal-oleate complexes. We synthesized as much as 40 grams of monodisperse magnetite
nanocrystals using 1 L reactor. Furthermore, the current synthetic procedure is very
general, and was successfully used to produce the nanocrystals of MnO, CoO, MnFe2O4,
CoFe2O4, and cube-shaped iron. By controlling the nucleation and growth processes, we
were able to synthesize monodisperse magnetite nanoparticles with particle sizes of 4, 6, 7,
8, 9, 10, 11, 12, 13, 14, 16 nm. We developed a new generalized synthetic route to produce
uniform-sized nanorods of Fe2P, FeP, Co2P, Mn2P, Ni2P from the thermal decomposition
of syringe-pump-delivered metal-surfactant complexes. The synthesized organic
dispersable nanocrystals were transformed to hydrophilic water-dispersable nanocrystals
by treating with phospholipids or PEG’s. The resulting water dispersable and
monodisperse nanocrystals of ferrites and oxides were successfully employed as new MRI
contrast agents. We fabricated monodisperse nanoparticles embedded in uniform
pore-sized mesoporous silica spheres. Monodisperse magnetite and CdSe/ZnS
nanocrystals (quantum dots) dispersed in organic media were transferred to aqueous phase
using CTAB stabilization. The subsequent sol-gel reaction of TEOS generated
monodisperse nanocrystals embedded in spherical mesoporous silica particles with an
average particle size of ~150 nm. The magnetic separation (guiding) was demonstrated for
the spheres. These mesoporous silica spheres embedded with nanocrystals were
investigated as drug delivery carriers using ibuprofen as a drug model and the controlled
release rate of ibuprofen by the surface modification was demonstrated.
D3 – Contributed Paper
SILICA-POLYPEPTIDE COMPOSITE PARTICLES
Paul S. Russo, Sibel Turksen, Erick Soto-Cantu, Jianhong Qiu, Department of
Chemistry, Louisiana State University, Baton Rouge, LA 70803;
chruss@LSU.edu
120
Core-shell composite particles have been prepared, each consisting of a silica-coated
cobalt center to which a homopolypeptide shell, either poly (ε-carbobenzyloxy-L-lysine)
or poly (γ-benzyl-L-glutamate), is attached covalently. Core particles were coated with a
mixture of reactive amino and passivating moieties through silylation reactions. The
amino groups initiated the polymerization, with attachment, of N-carboxyanhydride
monomers, resulting in a homopolypeptide shell. Core size and shell thickness can be
varied readily. Characterization by dynamic light scattering confirmed the helix-coil
transition of the polypeptide shell, reminiscent of the coat proteins of certain viruses,
through repeated heating and cooling cycles in an organic solvent. The living nature of the
polypeptide shell has also been confirmed. The particles have a size and uniformity that
leads to formation of colloidal crystals, and they modify phase relationships of solutions
containing rodlike polymers. Magnetometer measurements suggest the particles are
superparamagnetic. The sidechains of the shell polypeptides can be deprotected, rendering
the particles dispersible in aqueous media, where pH-induced size transitions are observed.
111
Oral Abstracts
D3 – Contributed Paper
SURFACE FUNCTIONALIZED NANO-MAGNETIC PARTICLES FOR
ADSORPTION/DESORPTION OF BIO-MOLECULES
Mohammad S Uddin, Kus Hidajat, Liang Hong, Zanguo Peng, Nabila
Shamim and Nguyen T K Thuyen; Department of Chemical and Biomolecular
Engineering, National University of Singapore, 4 Engineering Drive 4,
Singapore 117576, SINGAPORE; cheshahb@nus.edu.sg
121
Surface funcionalized nano-sized magnetic particles are recently gaining interest for its
application in the field of bio-separation. Due to their size, nano-particles provide large
specific surface area for adsorption of solutes and moreover the magnetic properties of
these particles offer an excellent tool to handle these particles in suspension by the use of
magnetic field. This paper deals with our work on nano-magnetic particles for purification
of protein and enzyme. The nano-magnetic particles (Fe3O4) were synthesized by chemical
precipitation of Fe2+ and Fe3+ salts at 80oC at alkaline condition and inert atmosphere and
the average particle size was about 10 nm. The particle surface was then functionalized in
two different ways: surface charge (electrostatic interaction) and coating with
thermosensitive polymer (hydrophobic-hydrophylic interaction). The particle surface
charge was controlled through the pH of the solution at isoelectric point of the solute. For
hydrophobic-hydrophylic interaction, the particles were coated with thermosensitive
polymer, Poly (N-isopropylacrylamide) (PNIPAM). Its lower critical solution temperature
is 32oC in water and changes from hydrophylic to hydrophobic above this temperature.
Adsorption and desorption of bovine serum albumin (BSA) and lysozyme were carried out
on these sruface functionalized particles. It was found that at pH of 4.7 (isoelectric point of
BSA) the adsorption of BSA was maximum (about 400 mg/g of dry solids at equilibrium
condition) compared to those of other pH values. At equilibrium, PNIPAM coated particles
adsorbed about 275 mg BSA/g dry solids and upon cooling to 25oC about 9% of the
adsorbed BSA was desorbed. The conformational and activity changes of BSA and
lyszyme due to the adsorption/desorption processes were studied. Analytical equipments
such as Transmission Electron Microscopy (TEM), Fourier Transform Infrared
Spectroscopy (FTIR), X-ray Photoelectron Spectroscopy (XPS) were used for particle
characterization and confirmation of adsorption/desorption processes.
D3 – Invited Paper
STRATEGIES FOR THE DESIGN AND READOUT OF ULTRAHIGH
DENSITY IMMUNODIAGNOSTIC PLATFORMS
H.-Y. Park, J. Driskell, K. Kwarta, B. Yakes, J. Uhlenkamp, R. Millen, N.
Pekas, J. Nordling,
R. J. Lipert, and M. D. Porter, Departments of Chemistry and Chemical
Engineering, Institute for Combinatorial Discovery, and Ames
Laboratory-USDOE, Iowa State University, Ames IA 50011, USA;
mporter@porter1.ameslab.gov
122
The drive for early disease detection, the growing threat of bioterrorism, and a vast range of
112
Oral Abstracts
challenges more generally in biotechnology have markedly amplified the demand for
ultrasensitive, high-speed diagnostic tests. This presentation describes efforts to develop
platforms and readout methodologies that potentially address demands in this arena
through a coupling of nanometric labeling with surface enhanced Raman spectroscopic,
micromagnetic, and scanning probe microscopic and readout concepts. Strategies will be
described for both the fabrication and readout of chip-scale platforms that can be used with
each novel readout modality. Examples will focus on the use of protein arrays as platforms
targeted for immumoassays in early disease diagnosis and the rapid, ultralow level
detection of cancer markers and viral pathogens. Each example will also discuss
challenges related to sensitivity and nonspecific adsorption and to fluid manipulation at
micrometer length scales.
D3 – Invited Paper
MAGNETIC NANOPARTICLES: APPLICATIONS BEYOND DATA
STORAGE
Andreas Hütten, Forschungszentrum Karlsruhe GmbH, Institute for
Nanotechnology, Hermann-von-Helmholtz-Platz, P.O. Box 3640, D-76021
Karlsruhe, Germany, andreas.huetten@int.fzk.de, and Inga Ennen, Günter
Reiss, University of Bielefeld, Dept. of. Phys., and Klaus Wojczykowski, Peter
Jutzi, University of Bielefeld, Dept. of. Chem., Universitätsstr. 25, D-33615
Bielefeld, Germany, andreas.huetten@int.fzk.de
123
Paramagnetic carriers, ranging from micro sized particles to nano sized colloids, which are
linked to antibodies enable highly specified biological in vitro cell separations as well as
therapeutic in vivo applications such as drug-targeting, cancer therapy, lymph node
imaging or hyperthermia. Ensuring biocompatibility and non-toxicity so as to meet the
requirements for these applications, iron oxide based particles, e.g. magnetite, are
commonly used as the magnetically responsive component of commercially available
magnetic microspheres. With the colloidal synthesis of superparamagnetic or
ferromagnetic Co and FePt nanocrystals with superior magnetic moments the question
arises whether these nanomagnets could replace the iron oxide particles as magnetic
carriers in in vitro separation and therapeutic in vivo technology. The potential of these
nanocrystals can directly be evaluated, comparing their magnetophoretic mobility under
identical experimental conditions. Chemical and physical aspects of their synthesis, the
resulting microstructure and magnetic properties will be discussed in detail. The synthesis
kinetics is modeled using a consecutive decomposition and growth model and is compared
to experimental data. It allows to uncover the three dimensional composition gradients of
these nanoparticles ranging from 1 to 10 nm. Potential in vitro and in vivo application will
be addressed as a function of the nanoparticles microstructure and morphology..
D3 – Contributed Paper
FUNCTIONALIZATION OF MAGNETIC NANOPARTICLES WITH
BIOMOLECULES
Shy Chyi Wuang, Koon Gee Neoh*, En-Tang Kang, Department of Chemical
124
113
Oral Abstracts
and Biomolecular Engineering, National University of Singapore 10 Kent
Ridge, Singapore 119260, Daniel W. Pack, Deborah E. Leckband, Department
of Chemical and Biomolecular Engineering, University of Illinois,
Urbana-Champaign, Urbana, IL 61801, USA; g0403162@nus.edu.sg;
chenkg@nus.edu.sg
Modifications were made on magnetic nanoparticles to tailor them for various biomedical
applications such as targeted drug delivery, hyperthermia and magnetic resonance
imaging. Superparamagnetic magnetite nanoparticles (Fe3O4) with average diameters ~6
nm were surface-functionalized with poly(N-isopropylacrylamide) (P(NP)) via
atom-transfer radical polymerization (ATRP) followed by the immobilization of heparin,
an anti-coagulant. The heparinized nanoparticles are able to delay phagocytosis by
macrophages and are effective in preventing thrombosis as demonstrated by their ability to
prevent blood clotting in vitro, for up to at least 24 hr, as compared to the normal clotting
time of about 4 min. Such nanoparticles are potentially very useful where targeted delivery
of heparin is desired, e.g. in the prevention or reduction of restenosis. On the other hand,
effective uptake of magnetic nanoparticles into cancer cells would be desirable for
hyperthermia treatment. In our project, magnetite nanoparticles are encapsulated inside a
conductive polymer, polypyrrole (PPY), via a miniemulsion polymerization. Fe3O4–PPY
nanospheres of about 100 nm in diameter and containing over 30% by weight of Fe3O4 can
be prepared by this technique. These nanospheres retained high levels of magnetization
(>20 emu/g) and electrical conductivity (~ 1 S/cm) and hence are potentially useful for
hyperthermia by deploying both the magnetic and conductive heating capacities.
Transmission electron microscopy (TEM) images have shown the distribution of Fe3O4 in
the PPY nanospheres to be roughly uniform. It was found that the choice of surfactant
affects the cell uptake of nanospheres. In particular, hyaluronic acid (HA) enhances the
adhesion of the Fe3O4–PPY nanospheres to cells and hence increases their cell uptake. The
Fe3O4–PPY nanospheres can be further functionalized to increase their potential for the
detection of cancer cells and treatment therapy.
D3 – Contributed Paper
PARTICLE POPULATION CLASSIFICATION BY MICRO-FLOW
IMAGING
Dave Thomas, David King, Peter Oma, Brightwell Technologies Inc., 195
Stafford Road West, Ottawa, Ontario, Canada, K2H 9C1;
dthomas@brightwelltech.com
125
The paper will describe a new particle analysis technology which employs automated
digital image analysis to classify particulate/cell suspensions. The technology involves
drawing sample through a sheathed or unsheathed micro-fluidic cell. Sections of the
flowing fluid are illuminated with a pulsed high-intensity source, magnified and imaged
frame-by-frame on the camera’s pixel array. The system software identifies, in real time,
pixels in each frame which are wholly or partially contained within a particle image. This
information is used to isolate particles and measure particle parameters such as count,
diameter, area, perimeter, circularity, and transparency. The volume of fluid sampled in
each frame is accurately known, therefore particle concentrations are determined
114
Oral Abstracts
absolutely. The database of images and parameter values is interrogated by the user to
produce histograms, scattergrams and to isolate sub-populations of interest. Micro-Flow
Imaging (MFI) technology will detect and classify particles ranging from 0.8 to 100
microns in size over a concentration range of 0 to 100K’s per ml. The technique is
insensitive to the particle’s optical properties and therefore offers distinct advantages over
laser diffraction and light obscuration in terms of anlyzing heterogenous populations. The
data set is intermediate between flow cytometry and manual microscopic analysis
providing the automation, statistical validity and reproducability of the former while
preserving the visual insight gained by the latter. Continuous sample introduction and
time-resolved image analysis permitting high resolution reaction monitoring and trend
charting. The paper will present experimental results applying MFI technology for general
purpose particle fabrication process control with particular emphasis upon characterization
and optimization of specific cell-related bio-processes including fermentation, viability,
purification, dissolution, preservation, and protein aggregation. Application of the
technology for detecting unwanted particulate within process fluids will also be presented,
as well as use of the technology for realtime chemical reaction monitoring.
D3 – Invited Paper
DEVELOPMENT OF MAGNETIC NANOPARTICLES FOR
BIOMEDICAL APPLICATIONS
Nguyen Thi Kim Thanh, Ian Robinson and David G Fernig, Centre for
Nanoscale Sciences, Department of Chemistry and School of Biological
Sciences, University of Liverpool, Crown Street, Liverpool L69 7ZD, United
Kingdom; ntkthanh@liverpool.ac.uk
126
Interest in metallic nanoparticles has grown rapidly in recent years due to their diverse
applications in biomedicines and novel materials for engineering devices. Magnetic
nanoparticles are of particular interest because of their potential application in areas such
as biosensing, targeted drug delivery and hyperthermia treatment of solid tumours as well
as high density magnetic storage. Magnetic nanoparticles composed of iron oxides are
currently used as image enhancers in magnetic resonance imaging (MRI). However iron
oxides have a relatively low saturation magnetisation, requiring these of larger particles.
Transition metal nanoparticles, e.g. those made from cobalt, have a much higher saturation
magnetisation value, allowing the use of small particles, without compromising their
magnetic response/sensitivity. Using the thermal decomposition of organometallic
compounds [Co2(CO)8 and Fe(CO)5] we have synthesised cobalt, iron and iron oxide
nanoparticles. By adjusting the reaction conditions, magnetic nanoparticles of various sizes
have been produced and by coating the particles with a variety of capping ligands, their
stability in aqueous solution and biological systems can be investigated. Gold has also been
used to coat iron and cobalt nanoparticles with a shell which, while protecting the tranision
metal core from oxidation and corrosion can also easily be functionalised, for example by
attaching peptides. Rationally selecting amino acids with structural and functional groups
possessing different properties can give an insight of the behaviour of magnetic
nanoparticles in aqueous and biological solutions. In particular, by changing the terminal
amino acid of the peptide chain the biofunctinalisation of the nanonparticles can be finely
115
Oral Abstracts
tuned, with the ultimate aim of producing a useful therapeutic tool. The synthesised
particles were characterised using TEM, SQUID and powder XRD.
E2 – Keynote Paper
LIPOSOMAL BUPIVACAINE: AN ULTRA-LONG ACTING LOCAL
ANESTHETIC
Gilbert J. Grant, Department of Anesthesiology, New York University
School of Medicine, 550 First Avenue, New York, NY 10016;
Gilbert.Grant@med.nyu.edu
127
Pain after surgery and trauma results in considerable suffering and has deleterious effects
on many physiological functions. Current pain management options have many
drawbacks, and pain is notoriously under-treated. Direct numbing of the painful site by
infiltration of local anesthetics is a treatment option that has many potential advantages,
and avoids the complications that may occur with currently available approaches. A key
drawback of using existing local anesthetics for infiltration is that the analgesia is of
limited duration, because the small local anesthetics (MW ~300) are rapidly redistributed
from the site of administration. To date, achieving prolonged analgesic duration requires
repeated injections or the use of an indwelling catheter, but insertion and management of
indwelling catheters requires highly skilled personnel, and are associated with a variety of
complications (e.g., infection). Thus, there is a compelling need for a safe and effective
local long-lasting analgesic. Liposomal bupivacaine was developed to meet this need. The
formulation is based on proprietary techniques that enable efficient loading of drug into the
liposome, resulting in a favorable drug-to-lipid ratio. In vivo assessment in animals and
humans has demonstrated that liposomal bupivacaine produces ultra-long acting analgesia.
The liposomes function as a depot from which the local anesthetics are slowly released,
and the mass of free drug in the extra-liposomal milieu is sufficient to inhibit axonal
conduction in the adjacent nerves. Furthermore, the slow drug release permits the safe
administration of a relatively large dose. Unlike standard local anesthetics, which are
quickly redistributed after injection, the liposomes tend to remain at the injection site.
These characteristics make liposomes promising agents for the safe and effective treatment
of pain. Their introduction into clinical practice is expected to revolutionize the way in
which pain is managed, and to provide relief for many millions of patients suffering from
painful conditions.
E2 – Invited Paper
APPLICATION OF LIPID BASED DRUG DELIVERY SYSTEM FOR
WATER INSOLUBLE DRUGS
Indranil Nandi, Sandoz, 2400 Route 130 N, Dayton, NJ 08810, USA;.
indranil.nandi@sandoz.com
128
In recent times up to 50% of new chemical entities are poorly water-soluble and therefore
largely show poor bioavailability. Lipid-based formulation approach is an effective tool to
improve oral absorption upon lipid digestion. Lipid based formulations, such as
116
Oral Abstracts
microemulsions are increasingly recommended for such candidates. Microemulsion is an
optically isotropic and thermodynamically stable system, which consists of water, oil,
surfactant and co-surfactant. Microemulsions are used as drug delivery systems because of
their solubilization capacity of poorly water-soluble compounds and enhancement of
topical and systemic drug availability. The presentation will cover formulation design of
lipid formulations. It will also covers issues related such as bioavailability, stability and
manufacturability. This presentation will also focus on the application and success of
microemulsion based formulations in the area of drug delivery. It also includes the
application of microemulsion for various routes of administration and provides insight on
the selection of pharmaceutically acceptable excipients for a stable lipid based delivery
system.
E2 – Invited Paper
PREPARATION OF THERMOSENSITIVE LIPOSOMES BY USE OF
AMPHIPHILIC BLOCK COPOLYMERS AND THEIR APPLICATION TO
ANTICANCER DRUG DELIVERY
Kenji Kono, Osaka Prefecture University, Department of Engineering, Sakai,
Osaka 599-8531, Japan; kono@chem.osakafu-u.ac.jp
129
Liposomes that release anticancer drug, doxorubicin (DOX), a few degree above
physiological temperature were designed by use of block copolymers of (2-ethoxy)ethoxy
ethyl vinyl ether (EOEOVE) and octadecyl vinyl ether (ODVE). The poly(EOEOVE)
block behaves as a thermosensitive moiety with the lower critical solution temperature of
about 40oC, whereas the poly(ODVE) moiety acts as anchor for the copolymer fixation
onto liposomal membranes. The DOX-loaded egg lecithin-choresterol liposomes modified
with the copolymer were prepared by hydration of a mixture of the lipids and copolymer
and subsequent loading of DOX into the liposomes by the pH-gradient method. It was
found that the copolymer-modified liposomes strongly enhanced the release of DOX above
the LCST of poly(EOEOVE): the release was completed withn 1 min at 45oC. Next,
distribution of the copolymer-modified liposomes in the body was examined by using
radioisotope-labelled liposomes. The liposomes were injected into teil vein of mice and
their distibution in the body was followed. Although the copolymer-modified liposomes
exhibited slightly longer blood circulation time than bare liposomes, these liposomes were
quite qickly taken up by liver. However, incorporation of poly(ethylene glycol)
(PEG)-bearing lipid effectively increased their circulation time. Finally, antitumor activity
of the DOX-loaded liposomes modified with the copolymer and PEG was investigated.
The copolymer-PEG-modified liposomes containing DOX were injected into teil vein of
mice bearing tumor. Tumor growth was slighly suppressed by the DOX-loaded liposomes
when the tumor was not heated. However, when the tumor was heated at 45oC for 10 min,
their efficacy for the suppresion of tumor growth increased dramatically. The same heat
treatment hardly affected tumor growth when temperature-insensitive PEG-modified,
DOX-loaded liposomes were injected. Therefore, it is likely that the
copolymer-PEG-modified, DOX-loaded liposomes accumulated at the tumor site
efficiently and released the anticancer drug responding to heat application, resulting in the
strong suppression of its growth.
117
Oral Abstracts
E2 – Invited Paper
PROMAXX MICROSPHERE DRUG DELIVERY TECHNOLOGY
Terrence L. Scott, Epic Therapeutics, A Wholly-Owned Subsidiary of Baxter
Healthcare Corporation, 220 Norwood Park South, Norwood, MA 02062 USA,
terrence_scott@baxter.com
130
Epic/Baxter hasdeveloped a simple, scaleable, water based process of protein microsphere
(PROMAXX) formation via controlled phase separation of the active agent in the presence
of water soluble polymers that generates microspheres with narrow size distributions. The
technology offers the capability for the fabrication of labile therapeutic proteins into
microspheres for pulmonary delivery via dry powder formulations with ideal
characteristics.The technology allows careful control of particle mean diameter as well as
the size ditribution of the microspheres. The microsphere fabrication technology has been
applied to human insulin, alpha-1-antitrypsin, human growth hormone as well as several
other proprietary therapeutic proteins. In all cases protein microspheres were fabricated in
an appropriate size range for pulmonary delivery (1-3 microns). The protein microspheres
were produced with narrow particle size distribution, high retention of integrity, and high
protein loading by a simple, cost efficient and scaleable process. The presentation will
provide case studies of the aerodynamic characteristics, the stability and the bioavailability
of several therapeutic proteins fabricated in the PROMAXX microsphere technology for
delivery of dry powders via the pulmonary route.
E2 – Invited Paper
DISLOCATION LOOP MEDIATED SMECTIC MELTING
Laurence Navailles, Patrick Moreau, Joanna Giermanska-Kahn, Olivier
Mondain-Monval, Frédéric Nallet and Didier Roux. Centre de Recherche Paul
Pascal, CNRS, avenue A. Schweitzer, F-33600, France ;
navailles@crpp-bordeaux.cnrs.fr
131
The role of topological excitations in driving phase transitions has long been a matter of
debate in several analogous three-dimensional condensed matter systems, namely
superfluids, superconductors, and smectics. These topological excitations are borne by
vortex (superfluids), magnetic flux (superconductors), and screw-dislocation (smectics)
lines. The underlying microscopic mechanisms have been discussed theoretically by
several authors and, as pointed out by most of them, analogous transitions should be driven
by analogous mechanisms. In spite of the universality of "topological melting", such a
mechanism has not yet been described experimentally. Here, we report the direct
observation of topological melting in an unusual lyotropic system in the vicinity of a
smectic – cholesteric (N*) phase transition. The proliferation of dislocations leads to at
least one, and possibly two intermediate phases, characterised by orientational ordering of
the dislocation loops and the subsequent unbinding of the screw-dislocation lines.
118
Oral Abstracts
M1 – Keynote Paper
PARTICLE ENGINEERING AND FORMULATION FOR ENHANCED
BIOAVAILABILITY OF POORLY WATER SOLUBLE DRUGS
Keith P. Johnston1, Xiaoxia Chen1, Jason McConville2, Jason Vaughn2, Kirk
Overhoff2, Michal Matteucci1, Matthew Todd Crisp1 and Robert O. Williams
III2; 1Dept. Chemical Engineering, Univ. of Texas Austin, 1 University Station
C0400, Austin, TX 78712; 2College of Pharmacy, Univ. of Texas Austin,
Austin, TX 78712
132
For poorly water soluble drugs, the clinical utility of available pharmaceutical dosage
forms can be limited. Novel technologies have been developed to form amorphous and
crystalline nanostructured particles of water insoluble drugs to enhance dissolution:
evaporative precipitation into aqueous solution (EPAS), spray freezing into liquid (SFL),
ultra-rapid freezing (URF) and controlled precipitation. The mechanisms of particle
formation and stabilization, as well as the enhancement in dissolution rates, are discussed.
The goal is to control nucleation and growth from solution to design particles with
desirable in vitro dissolution behavior to achieve high bioavailability in animal studies.
Strategies are reported for achieving high drug potencies up to 90%, yet with rapid
dissolution rates. With these technologies, the ability to arrest drug particle growth to
achieve high surface areas results from rapid phase separation and stablization of the
resulting particles with polymers and surfactants. A transport model has been developed to
predict dissolution from the micron to sub-micron size scale with a size-independent
interfacial rate constant for incorporation of the drug into micelles. Bioavailabilty results
are reported and analyzed in terms of in vitro data for mice, for oral and pulmonary
administration. These solution based approaches to produce nanostructured particles offer
several advantages over mechanical homogenization/milling processes including reduced
handling of solids, high yields, ease of incorporation of stabilizing excipients, ease of
scale-up, and control of crystallinity.
M1 – Invited Paper
PARTICLES FOR DRUG DELIVERY AND MEDICAL APPLICATIONS: A
SUPERCRITICAL APPROACH
Steven M. Howdle and Kevin M. Shakesheff∆ School of Chemistry and
School of Pharmacy∆, University of Nottingham, University Park, Nottingham.
NG7 2RD, UK; Vladimir K. Popov, Institute of Laser Technologies, Troitsk,
Moscow, Russia; Martin J. Whitaker, Critical Pharmaceuticals, BioCity,
Pennyfoot St., Nottingham
NG1 1GF, UK; steve.howdle@nottingham.ac.uk
133
119
Oral Abstracts
Supercritical carbon dioxide (scCO2) is a versatile and clean processing aid for
biodegradable polymers. We describe the use of scCO2 to prepare micron scale polymeric
particles loaded with proteins for application in drug delivery, and in the preparation of
novel laser fabricated surgical implants. Under mild conditions (ca. 35oC and 3000 psi)
scCO2 can very effectively plasticise (liquefy) a wide range of biodegradable polymers,
including poly(d,l-lactic acid), poly(lactide-co-glycolide), poly(caprolactone) and
poly(ethyleneglycol). Using suitable high pressure mixing apparatus, a wide range of
proteins can be dispersed throughout the liquefied polymer and by controlled pressure
release can be processed into monolithic blocks, fibres or particles of protein loaded
polymer. We will illustrate the principle using two protein based drug candidates; human
growth hormone (hGH) and granulocyte macrophage colony stimulating factor (GMCSF),
demonstarting that protein activity is retained and that the particles show sustained release
in-vitro of protein over a period of one month. We have further utilised such
supercritically prepared particles to create 3-D scaffolds with precise shape for tissue
engineering applications in cranio-facial surgery. Rapid prototyping via slective laser
sintering has been employed to develop protein loaded biodegradable scaffolds which also
retain protein activity.
M1 – Contributed Paper
INVESTIGATION INTO PARTICLE SIZE VARIATIONS WITH PROCESS
PARAMETERS USING NEKTAR SUPERCRITICAL FLUID
TECHNOLOGY
J. A. Green and A. Kordikowski, Nektar Therapeutics UK Ltd, 69 Listerhills
Science Park, Bradford, BD7 1HR; jgreen@uk.nektar.com
134
In the past, various supercritical fluid antisolvent techniques have been used to achieve
particle size reduction. However, conflicting results have been reported in the literature to
how operating parameters influence the particle size of a crystalline material. In this
investigation supercritical CO2 together with Nektar Supercritical Fluid Technology was
used for the precipitation of a pharmaceutical active from organic solution. The influence
of key process parameters (e.g. temperature, pressure, solution flow rate, etc) on the
particle size was investigated. Dry powder particle size was determined by Sympatec
analyser and particle morphology was studied by SEM. To determine the effect of the key
operating parameters on the particle size it is vital that the precipitated particles have a
small aspect ratio, as more lath and blade like particles tend to fracture during particle
sizing giving erroneous results. Further, the supercritical technique should show efficient
mixing of solvent and antisolvent in order to avoid the generation of erroneously large
particles. Additionally, variations in temperature and pressure during the precipitation step
should be kept to a minimum (i.e. no pressure fluctuations). Nektar Supercritical Fluid
Technology was used to precipitate a solution containing hydrochlorothiazide (HCT).
Operating pressures were varied between 75-200 bar and the temperatures between
298-353 K. Flow rates of CO2 were kept constant at 20 ml·min-1 and the solution flow rates
were varied between 0.1-1.6 ml·min-1. Further the solubility of HCT in modified CO2 and
solvent was measured under operating conditions to elucidate the influence of the residual
solubility in the fluid and the saturation level of the solution on the particle size.
120
Oral Abstracts
M1 – Invited Paper
NEW PARTICLE TECHNOLOGIES FOR DRUG DELIVERY
Boris Y. Shekunov and Pratibhash Chattopadhyay, Ferro Pfanstiehl
Laboratories, Pharmaceutical Technologies, 7500 E. Pleasant Valley Rd,
Independence, OH 44131, USA; shekunovb@ferro.com
135
The majority of drug products and drug delivery systems include particulate
pharmaceuticals. Consistent production of particulate materials, in relatively pure physical
forms as well as composite drug-excipient particles of various size, morphology and
structure can be described as “particle engineering”. In the recent years new therapeutic
applications, combined with increasing requirements for efficacy and safety of drug
delivery, call for a diverse “tool-box” of manufacturing techniques. The aim is to create
advanced manufacturing processes in terms of product consistency and quality.
Additionally the new processes developed should also provide means for enhanced drug
formulations not achievable using more conventional methods. Although many techniques
can be applied in laboratory, large-scale production presents many development hurdles.
This presentation will address the technology specifics in such application areas as:
•
New technologies of supercritical fluid extraction of emulsions, polymer
plasticization and spray-freeze drying; boundaries of different methods in the context
of drug-loading mechanisms, analytical issues and scalability.
•
Nanotechnology of water-insoluble drugs, polymer particles and lipid-based
formulations.
•
Optimized formulations for pulmonary drug delivery.
Composite particles of stable biological molecules immediate and controlled release.
M1 – Invited Paper
FORMATION OF DRUG NANOPARTICLES AND MICROPARTICLES
USING SUPERCRITICAL CO2
Ram B. Gupta, Department of Chemical Engineering, Auburn University,
Auburn, AL 36849-5127, USA; gupta@auburn.edu
Over past two decades, supercritical carbon dioxide (above 31.1 oC and 73.7 bar) has
emerged as a medium for the formation of micro- and nano-particles of pharmaceutical
compounds, due to the its adjustable solvent properties, high diffusivity, non-flammability,
and non-toxicity. Depending upon the solubility in supercritical CO2, two classes of
processes have emerged: (a) rapid expansion of supercritical solution (RESS) for CO2
soluble materials, and (b) supercritical antisolvent (SAS) for CO2-insoluble materials. In
RESS process, the drug material is first dissolved in supercritical CO2 and then expanded
through a nozzle to rapidly precipitate as particles. Since the expansion occurs as fast as
the speed of sound, the material comes out as small microparticles. But due to the limited
solubility of drugs in supercritical CO2, RESS process had limited utility, so far. In our
recently developed RESS-SC process by using menthol solid co-solvent, the solubility has
been enhanced by several hundred fold. The presence of the solid cosolvent also hinders
the particle growth; hence the particles in nanometer size range are easily obtained.
136
121
Oral Abstracts
Menthol is later removed by sublimation, yielding pure drug nanoparticles. In SAS
process, the drug material is first dissolved in an organic solvent. The solution is then
injected into supercritical CO2, resulting in the extraction of solvent by supercritical CO2
and precipitation of the material. Since, the speed of extraction is fast due to the high
(gas-like) diffusivity of supercritical CO2, the small microparticles of the material are
obtained. We have further enhanced the extraction speed by ultrasonic mixing which
results in nanoparticles. In the new process, the particle size is easily controlled by the
extent of ultrasonic power supplied. The strong extraction ability of supercritical CO2
allows the production of pure drug nanoparticles, free of any residual solvent or additives.
M1 – Invited Paper
DRUG DELIVERY APPLICATIONS OF PARTICLE TECHNOLOGY
USING CAN-BD PROCESSING
Robert E. Sievers, Brian P. Quinn, Jim A. Searles, Pradnya Bhagwat, Lia G.
Rebits, Aktiv-Dry, 6060 Spine Road, Boulder, CO 80301; Nurhan T. Dunford,
Dept. of Plant and Soil Sciences, Oklahoma State Univ., Stillwater, OK 74078;
Dexiang Chen, Debra Kristensen, PATH, 1455 NW Leary Way, Seattle, WA
98107; Mark T. Hernandez, Lowry Lindsay, Civil, Environmental and
Architectural Engineering, Univ. of Colorado, Boulder, CO 80309-0428; and
Stephen P. Cape, Chad S. Braun, David H. McAdams, Jessica A. Best, Jessica
L. Burger, Center for Pharmaceutical Biotechnology, Dept. of Chemistry and
Biochemistry, and CIRES, Univ. of Colorado, Boulder, CO 80309-0214;
rsievers@aktiv-dry.com
137
Formation of microparticles and nanoparticles by Carbon dioxide Assisted Nebulization
with a Bubble Dryer® (CAN-BD) permits aerosol pulmonary delivery of pharmaceuticals,
nutraceuticals, vaccines, antibiotics, and anti-virals. In addition, the creation of very finely
divided nanoparticles leads to faster rates of dissolution and enhanced bioavailability.
CAN-BD of phytosterols dissolved in ethanol, acetone or hexane leads to particles
averaging 100 nm in diameter that are rapidly dissolved in soybean oil. Aqueous vaccines
such as Hepatitis B surface antigen (HBsAg) adjuvanted with aluminum hydroxide
sometimes suffer freeze damage or heat damage. When stabilized with trehalose or
trehalose plus PVP, then dried by CAN-BD at 50 °C, the powders stored at temperatures
ranging from -20 °C to 66 °C for 43 days showed no loss of activity in vitro (ELISA) or in
vivo (mice) upon reconstitution in water for analysis or injection. Creating improved dry
powder vaccines for transport and use in developing countries where storage temperature
control is difficult is one of the main goals of the Grand Challenges in Global Health
initiative. Another goal is the creation of needle-free delivery systems. We are involved in
a program that will hopefully make contributions to both of these goals and have initiated
studies of the stabilization, micronization, and drying by CAN-BD of inhalable
live-attenuated measles virus vaccine. Initial results indicate powder stabilization with
trehalose and/or sucrose. Respirable particles of anti-tuberculosis drugs including
capreomycin, amikacin, ciprofloxacin, and moxifloxacin have been made by CAN-BD
from aqueous solutions. For rifampin, ethyl acetate was the solvent of choice and
supercritical nitrogen was the nebulizing dispersant. All five antibiotics maintained full
122
Oral Abstracts
activity after preparation by CAN-BD. The anti-viral pharmaceutical, Relenza®, was
dissolved in water and processed by CAN-BD to yield microparticles with MMAD of 2.4
µm and the respirable mass fraction was 73% < 5 µm.
M1 – Invited Paper
NANOPARTICLES FOR ENHANCED SOLUBILITY AND
BIOAVAILABILITY OF POORLY-WATER SOLUBLE DRUGS USING
SUPERCRITICAL FLUID TECHNOLOGY
Sibeum Lee, Min-Soo Kim, Jeong-Soo Kim, Hee Jun Park, and Sung-Joo
Hwang, National Research Lab of Pharmaceutical Technology, College of
Pharmacy, Chungnam National University, Yuseong-gu, Daejeon, 305-764,
Korea, sjhwang@cnu.ac.kr
138
Among many techniques for the preparation of solid dispersions, including milling, spray
drying, freeze-drying and solvent evaporation, supercritical fluid technology (SCF)
provides a novel alternative for formulating nano-sized co-precipitates that may be lower
in residual organic solvent and overcomes some of the problems faced in conventional
methods. In this study, solid dispersion nanoparticles containing felodipine, cefuroxime
axetil (CA) and itraconazole, respectively as poorly water-soluble drugs were prepared
using SCF process in an effort to increase its dissolution rate of drug and subsequently the
bioavailability. Their physicochemical properties in solid-state were characterized by
particle size, zeta potential, DSC, powder x-ray diffraction (PXRD), Fourier transform
infrared spectroscopy (FT-IR) and SEM. In addition, equilibrium solubility and dissolution
study were also carried out. The mean particle size of the felodipine solid dispersions was
200-250 nm; these had a relatively regular spherical shape with a narrow size distribution.
Pure CA was presented as irregular and flaky particles (size range ca. 5-10 μm) whereas all
solid dispersion nanoparticles prepared using SCF process at various ratios were presented
as regular and spherical particles (size range ca. 200-300 nm) with narrow particle size
distributions (PSDs). CA solid dispersion nanoparticles existed in the amorphous or
non-crystalline form. Dissolution studies indicated that the dissolution rates were
remarkably increased in solid dispersion nanoparticles, compared with those in physical
mixture and drug alone. The particle size of itraconazole solid dispersions ranged from 100
to 500 nm. The nanoparticles prepared at 60℃/10 MPa showed approximately 610-fold
increase in equilibrium solubility when compared to pure itraconazole. In conclusion, SCF
process could be a promising technique to reduce particle size and/or prepare amorphous
solid dispersion of drugs in order to improve the solubility and bioavailability of poorly
water-soluble drugs.
A4 – Invited Paper
DOUBLE DIRECT TEMPLATING OF PERIODICALLY
NANOSTRUCTURED ZNS HOLLOW MICROSPHERES
Paul V. Braun, Alejandro Wolosiuk, Onur Armagan, Univ. of Illinois at
Urbana-Champaign, Department of Materials Science and Engineering,
139
123
Oral Abstracts
Beckman Institute, and Frederick Seitz Materials Research Laboratory,
Urbana, Illinois 61801, USA; pbraun@uiuc.edu
Hollow capsules are both technologically and scientifically interesting. ‘Smart’ nano and
micro containers could lead new catalysts, structures for the controlled release of
chemicals, and materials that may even mimic some properties of living cells. Here we
present a ‘double direct templating’ approach to obtain hollow ZnS 500 nm diameter
microspheres perforated with a periodic array of uniform 2-3 nm diameter pores and
demonstrate the entrapment of Au nanoparticles and biological macromolecules within
these microspheres. In double direct templating, a lyotropic liquid crystal templates the
mineralization of ZnS on the surface of a silica or polystyrene colloidal template. Removal
of the templates results in a periodically mesostructured ZnS hollow capsule. Lyotropic
liquid crystal templating is in part useful for this process because of its simplicity and
ability to control structure on the nanoscale, using only the self-assembled structure formed
by the mixture of an amphiphilic molecule (e.g. a nonionic surfactant) with water to
template the formation of a mineral phase. The regular controlled pore structure of the
shell wall opens the possibility for the encapsulation of nanoparticles, polymers, and
biological macromolecules.
A4 – Invited Paper
SIGNAL BIOMOLECULE-RESPONSONSIVE GELS
Takashi Miyata, Faculty of Engineering, Kansai University, Suita, Osaka
564-8680, Japan; PRESTO, Japan Science and Technology Agency (JST);
tmiyata@ipcku.kansai-u.ac.jp
140
Stimuli-responsive gels that exhibit volume changes in response to environmental changes
such as pH and temperature have many future opportunities as suitable materials for
designing smart systems in biomedical fields. We have prepared a variety of
biomolecule-responsive gels by using biomolecular complexes as stimuli-responsive
cross-linking points. This paper describes two types of signal biomolecule-responsive gels
that undergo volume changes in response to signal biomolecules, which were prepared
using biomolecular complexes such as antigen-antibody complexes, saccharide-lectin
complexes and DNA duplexes. One is a biomolecule-crosslinked gel and the other is a
biomolecule-imprinted gel. The biomolecule-crosslinked gels can swell in the presence of
a targel biomolecule due to the dissociation of biomolecular complexes that play a role as
reversible crosslinking points. For example, the bioconjugated gels having
antigen-antibody bindings at cross-linking points swelled in the presence of a specific
antigen, but did not in the presence of other proteins. The antigen-responsive gels
controlled drug permeation in response to the antigen concentration. Furthermore, we
have prepared glucose-responsive gels and DNA-responsive gels as
biomolecule-crosslinked gels. On the other hand, biomolecule-imprinted gels can shrink
in response to a target biomolecule due to the complex formation between ligands and the
target molecule. As biomolecule-imprinted gels, we prepared glycoprotein-responsive
gels and DNA-responsive gels by biomolecular imprinting. Glycoprotein-responsive gels
were prepared by using lectin and antibody as ligands for a template tumor-marker
124
Oral Abstracts
glycoprotein in biomolecular imprinting. The glycoprotein-imprinted gels having both
lectin and antibody shrunk in a buffer solution containing the target glycoprotein.
Furthermore, biomolecular imprinting using single strand DNAs as ligands enabled us to
prepare DNA-responsive gels that can recognize SNPs. Thus, biomolecule-responsive
gels have many potential applications as smart biomaterials in biomedical fields. This
paper focuses on synthetic strategy of biomolecule-responsive gels and their responsive
behavior.
A4 – Contributed Paper
NANOPARTICLE PREPARATION OF α-LIPOIC ACID SUSCEPTIBLE TO
POLYMERIZATION
Chul ho Park, Jongwhi Lee; Department of Chemical Engineering and
Materials Science, Chung-Ang University, 221, Heukseok-dong, Dongjak-gu,
Seoul 156-756, Korea (South); jong@cau.ac.kr
141
Among various antioxidants, the redox system of alpha-lipoic acid (ALA) and dihydrolipoic
acid (DHLA) is an excellent antioxidant because both the reduced and oxidized forms retain
their functions of protecting defects related to blood flow and neurotrophins. Recent
medical studies confirmed their efficacy of not only anti-obesity but also appetite
suppression, as an overdose of ALA is taken (over 600 mg/kg). The dose might be reduced
into an acceptable range by improving the bioavailability of ALA. The reduction of crystal
sizes to nanometers in a drug delivery system can directly improve its bioavailability. There
are several restrictions in utilizing the general processes to prepare ALA nanoparticles such
as high shear homogenizing and ball milling, because cyclic five-membered disulfide is
susceptible to free radical ring-opening polymerization by friction heat. In wet
comminution, ALA of less than 0.01 M was reduced to DHLA whose thiol (-SH) can attack
the cyclic disulfide (SN2 reaction) and act as the initiator for ionic polymerization.
Therefore, this study focuses on how to prepare the nanoparticles of ALA without any side
chemical reactions like the polymerization. The temperature of surroundings during ball
milling was preserved at 4 °C in order to control that of ALA particles below 20 °C for 4
hours. As a result, we could produce ALA nanoparticles having the mean particle size of
300 nm with using a stabilizer, PVP (polyvinylpyrrolidone). To prove the possible
bioavailability improvement, nanoparticles and microparticles of ALA were injected to
standard rats. After 6 hours, the average amount of cumulative food intake of rats on ALA
nanoparticles was half as much as that of rats on ALA microparticles.
A4 – Contributed Paper
POLYELECTROLYTE MICROCAPSULES FOR BIOMEDICAL
APPLICATIONS
Bruno G. De Geest, Stefaan C. De Smedt and Jo Demeester, Department of
Pharmaceutics, Ghent University, 72 Harelbekestraat, 9000, Ghent, Belgium;
and Gleb B. Sukhorukov, IRC/Materials, Queen Mary University, Mile End
Road, E1 4NS, London,UK; br.degeest@ugent.be
142
125
Oral Abstracts
Due to it’s simplicity in preparation and multifunctionality, the advent of the layer-by-layer
(LbL) technique has led to an accelerated discovery in the field of organic thin films. In
brief, this technique is based on the sequential adsorption of charged species, such as
polyelectrolytes, onto an oppositely charged substrate. Using the LbL technique it is
possible to fabricate hollow microcapsules by coating a colloidal substrate followed by the
decomposition of the substrate. These microcapsules hold high potential for biomedical
applications. However, until now there are very few reports on polyelectrolyte
microcapsules which can decompose under conditions applicable in vivo. Here we present
three types of polyelectrolyte microcapsules sensitive to stimuli which can be evoked by
the human body:
(1) Self-exploding microcapsules consisting of a biodegradable microgel core surrounded
by a polyelectrolyte membrane. When the microgel core degrades a swelling pressure is
created which will finally rupture the surrounding polyelectrolyte membrane leading to the
release of the encapsulated material. Such microcapsules could be highly interesting for
single-shot vaccination as it could repleace the booster injections which are required to
generate sufficient immunity.
(2) Degradable microcapsules consisting of biopolymer polyelectrolyte multilayers which
can be degraded enzymatically or polyelectrolyte multilayers containing a polycation
whose cationic sidechains can be hydrolyzed. We show that these microcapsules can be
taken up and digested by living cells whereas microcapsules from synthetic
polyelectrolytes cannot be digested. These types of capsules hold potential for the targetted
deliery of therapeutics.
(3) Glucose responsive microcapsules fabricated using a novel synthesized polycation
containing phenylboronic acid as glucose sensitive moiety. We show that upon addition of
glucose the microcapsules are able to disassemble. This type of microcapsules could be
interesting to deliver insulin to diabetic persons only at that moment the glucose
concentration in the blood exceeds a critical value.
A4 – Invited Paper
ORAL NANOPARTICLE DELIVERY
James Talton, Nanotherapeutics, Inc., 12085 Research Drive, Alachua, FL
32615. jtalton@nanotherapeutics.com.
143
From wet-milling to nanometer-scale particle delivery, development of novel
pharmaceuticals, cosmetics, and over-the-counter 'nano'products is growing in interest.
Nanoparticle engineering technologies, initially focused on improving dissolution of
insolubles, has been proven to: 1) improve the oral bioavailability of insoluble and poorly
absorbed drugs that currently require injection (antibiotics, antivirals, anti-inflammatories,
and nutritionals). 2) enable oral delivery of macromolecules (peptide/protein) and 3)
provide pharmaceutical life-cycle management opportunities. This presentation will
present examples and attempt to compare several companies and technologies, making the
landscape of oral nanoparticle therapeutics clearer for different applications of interest.
126
Oral Abstracts
A4 – Invited Paper
DRUG-LOADED PROTEIN AND DNA NANO-MESO-MICROSPHERES
FOR NON-SYSTEMIC INTRATUMORAL CHEMOTHERAPY
Eugene P. Goldberg, Iris V. Enriquez, Shema Freeman, Amanda York
Biomaterials Center, Department of Materials Science & Engineering,
University of Florida, P.O. Box 116400, Gainesville, FL 32611, USA;
egold@mse.ufl.edu
144
The therapeutic activity of most cancer drugs is highly dose-dependant and systemic
toxicity such as myelosuppression, mucosistis, and cardiomyalgia usually prevents the use
of aggressive high dose chemotherapy. There is a consequent need for more efficient and
localized non-systemic drug delivery. We have therefore explored the synthesis of drug
loaded nano-meso-microspheres (meso-MS) and their application for intratumoral (IT)
chemotherapy. Recent research has been aimed at the development of clinically practical
compositions derived mitoxantrone (MXN) with biodegradable proteins (i.e. albumin,
collagen, casein) or with deoxyribonucleic acid (DNA) as the meso-MS matrix. The
synthesis developed in our laboratory involves steric stabilization of the aqueous
biopolymer solution dispersions in an organic polymer solution continuous phase (i.e.
cellulose acetate in tetrachloroethane) with crosslinking of the meso-MS uniquely via the
organic phase using glutaraldehyde or heavy metal ions in some cases for DNA. Some
emphasis has been on meso-MS compositions having 2-10 um particle size because of
favorable injectability of dispersions, good tumor tissue permeation and fixation, and
desirable surface area for efficient intratumoral drug release by diffussion and
bio-degradation mechanisms. Although in vivo evaluations have demonstrated excellent
tumor regression properties in murine models of ovarian and lung cancer, more recent
pre-clinical animal studies have been conducted in a breast cancer model, a subcutaneous
16/C murine mammary adenocarcinoma using female C3H/HeJ mice. Intratumoral
therapy with MXN loaded albumin meso-MS demonstrated greatly prolonged survival
(>300%) with no systemic toxicity at MS drug dose levels more than 7x the toxic dose for
conventional intravenous drug administration (48mg/Kg with meso-MS vs. 6.6mg/Kg for
i.v. drug). Results of these studies suggest promising opportunities for the clinical use of
intratumoral chemotherapy using drug loaded meso-MS to afford prolonged high drug
concentrations in tumors and tumor regression with minimal general toxicity; especially
for preoperative (neoadjuvant) chemotherapy to enhance outcomes for tissue-conserving
breast and lung cancer surgery.
A4 – Invited Paper
PREPARATION OF MAGNETIC POLYMERIC MICROSPHERES FOR
APPLICATION IN BIOMEDICAL FIELDS
Changchun Wang, Jianhua Hu, Wuli Yang and Shoukuang Fu, Department of
Macromolecular Science, Fudan University, and the Key Laboratory of
Molecular Engineering of Polymers, Ministry of Education, Shanghai 200433,
China; ccwang@fudan.edu.cn
145
127
Oral Abstracts
Because of the wide applications in the area of biomedical and biotechnological fields, a
great effort has been done to fabricate different kinds of microspheres with tailored
structural and surface properties over the last decade. Among them, stimuli responsive
microspheres are microspheres that show ability to change their physical-chemical
properties and colloidal properties in response to environmental stimuli such as changes of
temperature, pH, chemicals, light, electrical field, magnetic field or mechanic stress, etc.
These microspheres have been under intensive study for their high potential applications in
biomedical and biotechnological fields such as controlled drug delivery, biosensor,
chemical isolation, cell culture substrates, enzyme immobilization, bioelectrocatalysis, and
magnetically controlled electrochemical reaction. However, most of the reported stimuli
responsive microspheres only show response to one specific stimulus. Up to now, to the
best of our knowledge, only a few works have been directed to the fabrication of
microspheres which show response to more than one stimulus. In this paper, a series of
FITC-labeled magnetic PNIPAM microspheres with multi-resposive properties were
prepared. The FITC-labeled magnetic PNIPAM microspheres suspended in saline water
(0.9wt %) were introduced to the bodies of white rabbits. For comparison, a button magnet
(1000Gs) was posited at the liver of one of the test rabbits. The main visceral organs
including liver, spleen, lung, kidney and heart were taken out and sliced on
freezing-microtome, and the slices of every visceral organ were observed in fluorescent
microscopy to obtain the distribution of the FITC-labeled magnetic PNIPAM
microspheres. The experimental results showed that the FITC-labeled magnetic PNIPAM
microspheres have good magnetic target effect.
A4 – Contributed Paper
FABRICATION OF BIODEGRADABLE POLYMER MICRODEVICES
FOR CONTROLLED DRUG DELIVERY SYSTEMS
Aravind Chakrapani1, Nicholas J. Ferrell1, Derek J. Hansford1,2,3
1
Biomedical Engineering Center, Ohio State University, 2Department of
Materials Science and Engineering, Ohio State University, 3Ohio MicroMD
Laboratory, Columbus, OH 43212, USA; aravind@bme.ohio-state.edu
146
We report a novel soft lithography based technique to fabricate non-spherical
biodegradable polymeric microparticles of different sizes and shapes as drug delivery
systems. Geometrical control over the shape and size of these microparticles renders them
different aerodynamic and fluidic dynamic properties when compared to conventional
spherical microparticles and may prove to be beneficial in certain drug delivery strategies,
such as pulmonary and intravenous routes. The surface morphology of the particles was
studied using a scanning electron microscope and size distribution of the particles was
determined using a Coulter counter. The process is reproducible and millions of uniform
biodegradable particles of various sizes and shapes with dimensions ranging from 2-50
µm have been fabricated. In addition, we demonstrated encapsulation of a model drug
(FITC) and drug distributions within the particles were studied by confocal microscopy.
Particle size is a critical parameter for several aspects of controlled drug delivery
including control of drug-release kinetics, passive targeting to specific cell or tissue types,
128
Oral Abstracts
biodistribution upon administration and available routes of administration. In conclusion,
the uniform, biodegradable polymeric microparticles produced have potential to be used
in a variety of drug delivery applications and polymer-based microfabrication technology
holds promise to produce sophisticated, multi-functional drug delivery devices.
B2 – Invited Paper
W/O/W MULTIPLE EMULSIONS CONTAINING NITROIMIDAZOLE
DERIVATES FOR VAGINAL APPLICATION
Özgen ÖZER, Mine ÖZYAZICI, Ege University, Faculty of Pharmacy,
Department of Pharmaceutical Technology, 35100 Bornova-Izmir/Turkiye;
ozgen.ozer@ege.edu.tr
147
Vaginal trichomoniasisis a common problem frequently seen in clinical practice. While the
vaginal flora of healty women is dominated by a low pH (3.5-4.5), for women suffering
from vaginal infections an increase of the pH values is observed (>5). W/O/W multiple
emulsions have two layers and due to the double layers of the emulsifier, the multiple
emulsion facilitated transcutaneous passege of the water soluble substance compared to a
classic emulsion and it was pleasent to apply. The aim of this study was to formulate a
stable multiple emulsions containing two nitroimidazole derivates, metronidazole (MT)
and ornidazole (OR) for vaginal therapy. MT and OR were located different phases of
multiple emulsion and the in vitro release studies were realized in phosphate (pH 7) and
lactate buffer (pH 4.5) solutions to investigate better the effect of pH and location of active
substance on the release. The imaging studies were realized in rabbits following labeling
MT and OR with Technethium-99m (99mTc) to evaluate the in vivo absorption
characteristics. The percentage of MT and OR released from the multiple emulsions in
alkaline media were 3.2 and 2.8 fold greater than that observed in acidic media,
respectively, when they were introduced internal phase of the multiple emulsions. In this
case, it was also possible to protect them against an eventual degradation besides having a
prolonged release. 63.51 % of the administered OR dose remained in the rabbit’s vagina
after 2.5 hours. This value was calculated as 54.59 % for MT, according to the activity
detected from multiple emulsions and surrounding tissues. It was observed that especially
in alkaline medium a high release was found which was convenient for the vaginal
infections seen in the alkaline pH. It was concluded that W/O/W multiple emulsions were
locally effective in vagina and they could be introduced as a new drug carrier system for
vaginal delivery.
B2 – Invited Paper
MECHANISMS OF EMULSION STABILISATION BY COLLOIDAL
PARTICLES
Tommy S. Horozov and Bernard P. Binks, Surfactant & Colloid Group,
Department of Chemistry, University of Hull, Hull, HU6 7RX, UK;
t.s.horozov@hull.ac.uk
148
It is known that certain solid colloidal particles can attach to oil-water interfaces and act as
excellent emulsion stabilisers by forming a coherent particle layer around the emulsion
129
Oral Abstracts
droplets. It is accepted that the dense particle layers serve as a steric (mechanical) barrier
keeping droplets apart and making particle-stabilised emulsions completely stable for
years. There are, however, some rather puzzling results for stable emulsions with droplets
just sparsely covered with particles, which call under question the accepted mechanism of
stabilisation. Therefore the relation between the structure of particle monolayers, their
behaviour in isolated thin liquid films and the mechanism of stabilisation in
particle-stabilised emulsions is still unclear. We address this fundamental issue and present
experimental results demonstrating the link between particle behaviour and interactions in
planar monolayers, thin liquid films and the mechanisms of emulsion stabilisation. We
show why strongly repulsive colloidal particles, which give well ordered dilute planar
monolayers, can act as very effective emulsion stabilisers. This is due to the spontaneous
particle accumulation in a dense monolayer bridging the emulsion droplets sparsely
covered with particles, thus preventing coalescence, as revealed by direct in situ
microscope observations. Our results imply that two general mechanisms of emulsion
stabilisation by solid particles thus exist: (i) steric stabilisation of emulsion droplets
covered by coherent particle layers and (ii) stabilisation by particle bridges when droplets
are sparsely covered. This is very important for understanding the fundamentals of
solid-stabilised emulsions and designing more efficient particle stabilisers.
B2 – Invited Paper
PREPARATION OF BIODEGRADABLE NANOPARTICLES BY A
MEMBRANE BASED PROCESS
K. Ebert, A. Ahmad, R. Just GKSS Research Centre Geesthacht GmbH,
Max-Planck-Str. 1, 21502 Geesthacht/ K. Lützow, M. Scholz GKSS Research
Centre Geesthacht GmbH Kantstr. 55, 14513 Teltow, Germany;
katrin.ebert@gkss.de
149
Nanoparticles and nanocapsules are of special interest since they are effective carriers for
different substances such as pharmaceutical agents, genes, proteins and peptides.
Nanoprecipitation is a method capable for the lab-scale preparation of such particles with
low mean particle size and low polydispersity. Briefly, a solution consisting of a polymer
and a solvent is poured into a non-solvent bath containing a surfactant under agitation.
Phase inversion occurs due to diffusion of solvent into the non-solvent bath. As a
consequence, polymer precipitation occurs. The nanoparticles are stabilized by a
simultaneously formed shell of surfactant molecules on the surface of the nascent particles.
The direct scale-up of this method, however, results in particles with significantly less
uniform particle size distribution. The aim of our work was the development of a process
allowing large-scale manufacture of nanoparticles and nanocapsules with uniform particle
size distribution. The new process utilizes porous membranes through which the polymer
solution is homogeneously permeated into a circulating aqueous phase. So far, experiments
with flat porous membranes of poly(acrylonitrile) (PAN) revealed that under the chosen
conditions the polymer concentration has the strongest influence on the mean particle size
while the concentration of the surfactant in the aqueous phase is determining the
polydispersity of the nanoparticles.
130
Oral Abstracts
B2 – Invited Paper
NEW FUNCTIONS OF GRAFTED-POLYMER LAYERS OF
CORE/CORONA POLYMER NANOSPHERES IN BIOSEPARATION
Hidekazu Yoshizawa, Shintaro Abe and Tsutomu Ono, Graduate School of
Environmental Science, Okayama University, Okayama 700-8530, Japan;
yhide@cc.okayama-u.ac.jp
150
Aqueous two-phase system is known for extraction technique for protein purification.
Poly(ethyreneoxide)/dextran (PEO/Dex) system and poly(N-isopropyl
acrylamide)/dextran (PNIPAAm/Dex) system are, for example, representative systems of
aqueous two-phase system. The difference of hydrophobicity between two kinds of
water-soluble polymer is mainly responsible for the partitioning of proteins. Whereas,
functional polymeric nanospheres have large specific surface area and provide the noble
separation field. We prepared core/corona polymeric nanospheres and examined the
mechanism of protein adsorption on functional polymeric nanosphere. In this study, we
report the behavior of protein partitioning between the grafted polymer layer on polymer
nanospheres and Dex solution. Polymer nanospheres with PEO corona layer were prepared
by dispersion copolymerization of PEO macromonomer and styrene. Whereas, PNIPAAm
grafted polymer nanospheres were prepared by seed dispersion polymerzation. The
prepared polymer nanospheres were dispersed in Dex solution and we observed the
formation of aqueous two-phase partitioning system on the surface of polymer
nanospheres. Proteins, phycocyanin and hemoglobin, were partitioned to PEO-rich phase
and Dex-rich phase in liquid-liquid system, respectively. In nanosphere system, the similar
tendency of protein partition was observed, that is, phycocyanin partitioned to PEO-core
on nanosphere and hemoglobin partitioned to Dex solution. Untill now, phase separation in
PNIPAAm/Dex system has been reported. However, we newly observed this system
showed reversible thermosensitibily below the LCST of PNIPAAm. This phenomenon can
be expected to realize thermo-sensitive purification system of proteins. Therefore, we
carried out the protein partitioning in this system. Consequently, hemoglobin partitioned in
Dex solution in liquid-liquid system was concetrated in solution phase of nanosphere
system and lysozyme partitioned in PNIPAAm solution in liquid-liquid system was
tranfered in PNIPAAm-gratfted layer in nanosphere system. This partitioning tendency in
PNIAAm/Dex system was the same as the obtained result in PEO/Dex system.
B2 – Invited Paper
RAPID STABILITY TESTING AND SHELF LIFE DETERMINATION OF
CONCENTRATED EMULSIONS
Dietmar Lerche, Stefan Küchler, Titus Sobisch, Torsten Detloff and Dean
Abadzic°, L.U.M. GmbH, Rudower Chaussee 29, 12489 Berlin, Germany;
d.lerche@lum-gmbh.de, °LUM Corp., 200 Boston Ave., Suite 2900, Medford,
MA 02155, dean@lumanalytical.com
151
Many dispersions in the daily life are colloidal systems based on emulsions, partly
containing additionally solid particles to improve their performance. The long term
stability of the “quality” of emulsion based products is crucial, as between the production
131
Oral Abstracts
date and the time of their use or consumption often weeks and even month are passed by.
Shelf life depends directly on physical stability besides other phenomena like degradation
phenomena by light or alterations of emulsion’s texture. Centrifugation is the only method
truly to accelerate physically sedimentation or creaming processes of emulsions and
dispersions. Furthermore, analytical photocentrifugation is a very efficient tool to
determine the demixing velocity. In this paper we demonstrate that from these velocities
the shelf life may be directly determined. We present a SOP, how the influence of the
elevated g-forces may be evaluated based on the analysis of a velocity versus g-force
(centrifugal acceleration) dependency. Shelf life at gravity (1 xg) can be confidently
calculated based on the linear or non-linear regression lines. Besides shelf life these studies
reveal additional information regarding the structural (rheological) stability of emulsion
based products.
B2 – Contributed Paper
CERAMISPHERES: CONTROLLED RELEASE FROM SOL-GEL MICRO
AND NANOPARTICLES
Christophe J. Barbé, Kim Finnie and Linggen Kong, CeramiSphere, ANSTO,
PMB1, Menai NSW 2234, Australia; cab@ansto.gov.au
152
We present a generic approach to the synthesis of sol-gel silica matrices for encapsulating
bioactive species, and controlling their subsequent release over periods ranging from hours
to months. The bioactive species are incorporated into the matrix during gelation at, or
near, ambient temperature, and remain entrapped until the gels are immersed in solution.
The release profile can be tailored by controlling the internal structure of the gels (pore
volume, size and tortuosity, and surface chemistry). In turn, the gel structure can be
precisely tailored by varying such sol-gel processing parameters as the water-to-alkoxide
ratio, pH, alkoxide concentration, ageing, drying time and temperature. Hence, the release
rate of the encapsulated species is controlled by adapting the structure of the internal pore
network to the physico-chemical properties of the active molecule. Combining emulsion
synthesis with sol-gel technology enables the carrier to be produced in the form of
mono-dispersed spherical particles, with an average size that can be varied from 50 nm to
50 µm. The particle diameter is determined by the size of the reverse micelles, which is
controlled by the hydrophile-lipophile balance between the surfactant, aqueous phase and
non-polar solvent. The release rate of the encapsulated species is controlled by the internal
nanostructure of the spheres, which can be tailored (as in bulk gels) by varying the sol-gel
chemical parameters. Another key feature of this process is its versatility, which allows the
encapsulation of a wide range of actives, from simple hydrophilic dyes to larger
biomolecules or nanocrystals. The combined versatility and independent control over the
release rate and particle size gives this technology considerable potential as a delivery
solution in the food, homecare, chemical, biocide, pesticide, cosmetic and pharmaceutical
markets.
132
Oral Abstracts
B2 – Invited Paper
CATIONIC ALBUMIN CONJUGATED PEGYLATED NANOPARTICLE
AS NOVEL DRUG CARRIER FOR BRAIN DELIVERY
Wei Lu, Xinguo Jiang. PO Box 130, Department of Pharmaceutics, School of
Pharmacy, Fudan University (Fenglin Campus), 138 Yi Xue Yuan Rd,
Shanghai 200032, P.R. China; stephenlu0681@163.com
153
A novel drug carrier for brain delivery, cationic bovine serum albumin (CBSA) conjugated
with poly(ethyleneglycol)-poly(lactide) (PEG-PLA) nanoparticle (CBSA-NP), was
developed and evaluated. Copolymers of methoxy-PEG-PLA and maleimide-PEG-PLA
were synthesized by ring opening polymerization of D,L-lactide initiated by methoxy-PEG
and maleimide-PEG, respectively, which were applied to prepare pegylated nanoparticles
by means of double-emulsion and solvent evaporation procedure. Native bovine serum
albumin (BSA) was cationized and thiolated, followed by conjugation through the
maleimide function located at the distal end of PEG surrounding the nanoparticle’s surface.
To evaluate its blood-brain barrier (BBB) transcytosis and toxicity against BBB
endothelial tight junction, we have explored a method of coculture with rat brain capillary
endothelial cells on the top of micro-porous membrane of cell culture insert and rat
astrocytes on the bottom side. BSA conjugated with pegylated nanoparticles (BSA-NP)
was used as control group and 6-coumarin was incorporated into the nanoparticles as a
fluorescent probe. Transmission electron micrograph showed CBSA-NP had a round and
regular shape with a mean diameter around 100 nm. The unchanged permeability of
14
C-labeled sucrose comparing to that of the sucrose in the appearance of 200 μg/ml of
CBSA-NP proved that CBSA-NP did not impact the integrity of BBB endothelial tight
junction. Permeability of CBSA-NP was about 7.76 times higher than that of BSA-NP,
while the transcytosis was inhibited in the excess of free CBSA, indicating that CBSA-NP
underwent absorptive-mediated transcytosis. Thirty minutes after a dose of 60 mg/kg
CBSA-NP or BSA-NP injection in mice caudal vein, fluorescent microscopy of brain
coronal sections showed a higher accumulation of CBSA-NP around the lateral ventricle,
third ventricle and periventricular region than that of BSA-NP. This indicated CBSA-NP
preferentially transported across BBB with little toxicity, which offered the possibility to
deliver therapeutic agents to brain.
B2 – Invited Paper
COLLOIDAL EMULSION APHRONS: STRUCTURE, PROPERTIES,
PRINCIPLES AND APPLICATIONS
Yujie Dai, Tianjin Key Laboratory of Industrial Microbiology, College of
Biotechnology, Tianjin University of Science and Technology, Dagu Nanlu
1038, Tianjin, 300222, China; Tong Deng, Institute of Process Engineering,
Chinese Academy of Sciences, P.O. Box 353, Beijing, 100080, China;
yjdai@126.com
154
Colloidal emulsion aphrons (CEAs) can be considered as the micron-sized water-in-oil
emulsion-cores encapsulated by a “soapy shell” consisting of multi-layer surfactant
molecules. In this paper, their structure and some properties are summarized. The
133
Oral Abstracts
principles and affecting factors on CEA extraction are introduced. In addition, the CEA
applications to drug over dose, detoxification and fine particle preparation were also
investigated. It is similar to emulsion liquid membrane system. The mechanism for CEA
separation can be approximately divided in two types. Type I (physical separation) and
type II (carrier-facilitated diffusion). For type I mechanism, the solute transport across the
soapy shell and the membrane is driven by the ability of the desired species to partition into
the membrane phase and its diffusion rate through the membrane and the soapy shell. But
for the solute which is not soluble in membrane, a carrier has to be used in the intervening
membrane phase, which binds and releases the solute at the external and internal interfaces
successively, allowing diffusion of the solute-carrier complex through the liquid
membrane. This approach constitutes type-II carrier-facilitation mechanism. For type I
separation, the CEA application to drug overdose treatment was studied using salicylic
acid as the model drug, paraffin oil as the membrane phase, PEG-30 dipolyhydroxystearate
(P135) as the hydrophobic surfactant, nonylphenol ethoxylate-10 (NP10) as the
hydrophilic surfactant and NaOH solution as the receptor phase. When the pH value of the
donor phase was lower than 2.0 and the suitable NaOH concentration of the receptor phase
was higher than 0.02mol/L, more than 98.7% of salicylic acid was transported into receptor
phase in half a minute. For type II separation, the heavy metal removal from the donor
phase was studied with Cu2+ as a model ion, di-(2-ethylhexyl) phosphoric acid (D2EHPA)
as a carrier, paraffin oil as the membrane phase, PEG-30 dipolyhydroxystearate (P135) as
the hydrophobic surfactant, nonylphenol ethoxylate-10 (NP10) as the hydrophilic
surfactant and EDTA solution as the receptor phase. The result showed that it only needed
3 minutes when 99.3% was removed from the outer donor phase with CEAs whereas it
needed nearly 60 minutes for ELM extraction. The examples above exhibit the quick
separation ability of CEA dispersion. Colloidal emulsion aphrons can also be used as a
microreactor to synthesize fine powder materials. With ascorbic acid as reductant in inner
phase, Ag+ was transferred into inner phase of CEAs and reduced to form fine silver
particles. “Nano porous microsphere” of silver was synthesized by adjusting
concentrations of stripping regent, solute and carrier, and also characterized by field
emission scanning electron microscope(SEM).
C2 – Keynote Pape
ENCAPSULATION OF DRUG NANOPARTICLES IN SELF-ASSEMBLED
MACROMOLECULAR NANOSHELLS
Michael Pishko, Department of Chemical Engineering, 204 Fenske
Laboratory, The Pennsylvania State University, University Park, PA
16802-4400. mpishko@engr.psu.edu
155
A layer-by-layer (LbL) self-assembly technique was used to encapsulate core charged drug
particles in a polymeric nanoshell. This approach provides a new strategy in the
development of polymeric vehicles for controlled release and targeting to diseased tissues
and cells specific to human illness, such as cancer. A nanoshell composed of two
biopolymers, poly-L-lysine and heparin sulfate, were assembled stepwise onto core
charged drug nanoparticles. The exterior surface of the nanoshell was functionalized with
biocompatible and targeting functional moieties, poly(ethylene glycol) (PEG) and folic
134
Oral Abstracts
acid, respectively. Drug nanoparticles of dexamethasone, taxol, and 5-fluorouracil were
fabricated using a modified solvent evaporation technique, producing particles within a
range of 314.0 to 154.7 nm. Surface morphology of the encapsulated drug nanoparticles
were viewed by TEM and SEM. TEM images indicated that the nanoshell was
approximately 5 nm, and composed of two polyelectrolyte layers. Characterization of
surface chemistry and charge of the nanoshell required the use of XPS and zeta potential,
respectively. XPS data collected for PEG modified drug nanoparticles confirmed that the
peak at 286 eV represented the repeat unit in a PEG molecule. Zeta potential results
re-confirmed PEG’s presence at the surface. Chemisorption of PEG molecules neutralizes
the surface of the nanoshell and this was illustrated by the measured neutral zeta potential
of the drug particles. Preliminary biocompatibility studies to study phagocytosis of PEG
modified drug particles were performed using a flow cytometric assay and suggested that
the neutral charge of the nanoshell results in decreased phagocytosis after 24 hours of
incubation.
C2 – Invited Paper
EFFECT OF DRUG CHARACTERISTICS ON THE DEGRADATION
MECHANISM AND DRUG RELEASE RATE FROM BIODEGRADABLE
POLYMER MATRICES
Nily Dan, Department of Chemical and Biological Engineering, Drexel
University, Philadelphia PA 19104; dan@coe.drexel.edu
156
We compare the degradation and release of six different drugs from 50:50 poly
lactic-co-glycolic acid: Thiothixene, Haloperidol, Hydrochlorothiozide, Corticosterone,
Ibuprofen, and Aspirin. Despite using the same polymer matrix and drug loading (20% by
weight), we find that the rate of polymer degradation and the drug release profile differ
significantly between the drugs. We conclude that the design of biodegradeable polymeric
drug carriers with high drug loadings must account for the effect of the drug on the polymer
degradation and drug release rate.
C2 – Contributed Paper
INVESTIGATION INTO THE INFLUENCE OF FATTY ACID PURITY ON
THE DRUG RELEASE BEHAVIOR OF TASTE-MASKING FATTY ACID
MICROSPHERES
Sheng Qi, Duncan Q.M. Craig, School of Chemical Sciences and Pharmacy,
University of East Anglia, Norwich NR4 7TJ, UK; and David Deutsch,
GlaxoSmithKline Research and Development, Ware, Herts SG12 0DP, UK;
sheng.qi@uea.ac.uk
157
Stearic acid has been used in pharmaceutical manufacturing for decades. However,
commercial grade stearic acid contains a range of further fatty acids, including up to
50%w/w palmitic acid. The presence of "foreign" saturated fatty acids may significantly
alter the performance of a fatty acid based formulation. In this study, taste-masking
microspheres were prepared by a spray chilling technique using pure stearic acid, pure
135
Oral Abstracts
palmitic acid, and mixed stearic and palmitic acids (50:50 %w/w and 30:70 %w/w). The
mixed fatty acid formulations were found to have the fastest drug release in alkaline media.
DSC and XRPD were utilized for characterizing the fatty acid microspheres before and
after exposure to alkaline media. Additional peaks associated with the formation of fatty
acid-soaps were observed in the DSC and XRPD results of the microspheres after exposure
to the alkaline buffer. The results of both techniques indicated that a lower amount of fatty
acid-soap was formed in the single fatty acid systems than in the mixed systems. In order to
gain a fuller understanding of this phenomenon, the behavior of fatty acid molecules at the
interface of air/alkaline media were investigated using surface pressure-area isotherm
measurements. It was noted that under a constant surface pressure (30mN/m) the surface
area per molecule of the mixed systems decreased as a function of time. This reduction in
film stability of mixed monolayers is a result of disrupted molecular packing in the
monolayer. Neutron reflection experiments revealed that palmitic acid is partially soluble
in the buffer and contributes to the instability of the mixed fatty acid monolayers. The
combined effects of the dissolution of palmitic acid and the formation of fatty acid soaps
may be responsible for the observed behaviour of mixed fatty acid microspheres and the
difference in behaviour between "pure" and mixed systems.
C2 – Contributed Paper
FUNCTIONAL MICRO-ENCAPSULATION USING HYBRID
MATERIALS
Jacco Eversdijk and Sabine Fischer, TNO Science and Industry, De Rondom
1, Eindhoven 5612AP, The Netherlands; jacco.eversdijk@tno.nl
158
Micro-encapsulation is a method to enclose active ingredients in a shell material on a
micron-sized scale. The main purpose of this technology is to protect the core material
from environmental effects that could diminish or even destroy the functionality of the
active compound. In most existing encapsulation technologies polymers are used as the
encapsulating shell material. The performance of the encapsulation is therefore limited by
the inherent properties of the applied polymeric material. At TNO Science and Industry,
expertise has been obtained in hybrid materials consisting of (modified) inorganic
nano-particles in polymeric matrices. The introduction of these in-organics can change the
physical properties of polymers significantly. We are using these hybrid materials in
functional encapsulating in order to increase or optimize desirable properties and
functionalities such as barrier and controlled release. Although intelligent choice in
polymeric shell-material can result in more or less satisfactory properties, a true selective
optimization is mostly difficult to achieve. The introduction of (modified) nano-scaled
inorganic particles in micro-encapsulation can offer an additional tool to the technology.
The resulting hybrid material combines the standard polymeric encapsulation materials
with modifiable inorganic nano-particles (either synthetically made or natural occurring).
Through parameter such as: type of modification, shape and size of the mineral structure,
an extensive toolbox is available to tune desired properties of the shell material such as:
(oxygen) barrier, slow release and possibly release on demand. Results from ongoing
research will be presented. Furthermore, a newly developed method of measuring the
oxygen permeability of encapsulating materials will be presented. Said method uses the
136
Oral Abstracts
non invasive OxySense technology, based upon the fluorescence quenching, in the
presence of oxygen, of a metal organic fluorescent dye immobilized in a gas permeable
polymer, in combination with coated films of the encapsulation material.
C2 – Invited Paper
ACRYLATE-BASED NANOGELS AS MICROCAPSULAR MEMBRANE
COMPONENTS FOR PEPTIDE DELIVERY
Hideki Ichikawa, Faculty of Pharmaceutical Sciences and Cooperative
Research Center of Life Sciences, Kobe Gakuin University, Arise 518,
Ikawadani-cho, Nishi-ku, Kobe 651-2180, Japan,
ichikawa@pharm.kobegakuin.ac.jp
159
Significant advances in biotechnology and biochemistry have led to the discovery of a
large number of biologically active peptides for therapeutic use. In general these peptides
have relatively short half-lives, requiring appropriate controlled release systems for better
therapy. Controlled release of peptides is, however, not as easy as that of conventional
drugs because their large molecular size is much more dramatic in hindering the diffusion
and release from polymeric devices. From this perspective, we have been developing two
types of microcapsular devices containing new acrylate-based nanogels with a specific
solute-permeability for delayed- or thermosensitive-release of peptide drugs. The
microcapsule preparation was accomplished by an air suspension coating process. A
nanogel particle of acrylic terpolymer, ethyl acrylate-methyl methacrylate-2-hydroxyethyl
methacrylate, was newly synthesized by emulsion polymerization to construct
delayed-release microcapsules. By spray-coating the insulin-loaded lactose particles with
the nanogels of acrylic terpolymers, microcapsules showing a pH-independent
delayed-release profile can be obtained. The lag time of insulin release was adjustable by
the membrane thickness. Oral administration of the microcapsules with the lag time of 6
hours to beagle dogs resulted in significantly reduced blood glucose concentration, leading
to colon-specific insulin delivery with pharmacological availability of 5%. Meanwhile,
nanogel particles of poly(N-isopropylcarylamide) (p(NIPAAm)) with a reversible
temperature-dependent swelling property were prepared by dispersion polymerization to
fabricate a microcapsular membrane with thermosensitively changeable permeability. The
microcapsules constructed by coating of drug-loaded CaCO3 particles with blend mixture
of the p(NIPAAm) nanogels and ethylcellulose pseudo-latex exhibited an ‘on-off’
positively thermosensitive drug-release, i.e., the release rate was remarkably enhanced at
temperatures above a lower gel collapse point (temperature for complete deswelling) of
32˚C possibly due to the formation of voids through the shrinkage of p(NIPAAm) nanogels
in the membrane. A possible application of this type of microcapsules can be found in
externally temperature-activated pulsatile delivery of peptide drugs.
C2 – Invited Paper
THERMOSENSITIVE MAGNETIC NANO- AND MICROCARRIERS AS
CONTACTLESS CONTROLLABLE DRUG CARRIERS AND TOOLS
D. Müller-Schulte, MagnaMedics GmbH, Martelenberger Weg 8, D-52066
160
137
Oral Abstracts
Aachen, Germany, P.Borm, Hogeschool Zuyd, NL-6400 Heerlen, The
Netherlands; detlef.mueller2@post.rwth-aachen.de
By encapsulating magnetic colloids into a thermosensitive polymer matrices such as
N-isopropylacrylamide and hydroxypropylcellulose, for the first time contactless
controllable and manipulable nano- as well as micro carrier systems (stimulus-response
carriers) can be prepared. The unique feature of these polymers is that a phase transition
accompanied by a drastic shrink process occurs at temperatures above 30°C. By
encapsulating ferro(i)magnetic colloids into the polymer matrix and exposing these
magnetic beads to an external high frequency magnetic field (induction coil),the
subsequent shrink process can be contactlessly induced. This process is reversible, i.e. the
shape of the polymer goes back to its original form once the initial temperature has been
reached again. The fundamental principle can be exploited for the construction of
controllable stimulus-response carriers or, alternatively, nano- and micro tools. This
stimulus response principle is the basis for a novel type of drug carrier. For this purpose
biologically active substances (e.g. anticancer drugs) are encapsulated together with the
magnetic colloid into the polymer matrix. The subsequent inductive heating above the
critical phase transition temperature which is simultaneously accompanied by the
de-swelling of the polymer (shrink process) leads to an immediate release of the
encapsulated drugs. Depending on the size of the polymer carrier, this drug release occurs
over a period of 2 to 5 minutes, thus making these carriers an ideal controllable drug depot.
The proof of principles of the novel therapy approach is demonstrated using cancer drug
model and doxorubicine.
C2 – Invited Paper
MICROPARTICLE FORMULATION DEVELOPMENT –
CONSIDERATIONS FROM BENCH-TOP TO CLINICAL
MANUFACTURING
Peter Markland, Brookwood Pharmaceuticals, 756 Tom Martin Drive,
Birmingham, AL 35211; pmarkland@brookwoodpharma.com
161
Successful results from initial feasibility (or proof-of-concept) studies can place
considerable pressures on product development programs to advance forward as rapidly as
possible through the formulation selection, optimization, and scale-up process and on
towards clinical testing (or first-in-man trials). This is true even for non-traditional dosage
forms such as long-acting implantable microparticle (or microsphere) formulations. In
addition to the obvious need to identify the formulation or composition that gives the
desired in vivo release profile, there are numerous other factors that must be considered to
help facilitate an efficient and successful product development program. This presentation
will briefly review issues affecting the scale-up of emulsion-based microparticle
(microsphere) processes. Following this introduction, the discussion will then describe in
more detail other factors that can impact the successful development of a microparticle
formulation program as it moves from bench-top on forward towards manufacturing of
first-in-man clinical trial supplies.
138
Oral Abstracts
C2 – Contributed Paper
VIBRATING NOZZLE PROCESSING IN INDUSTRIAL
MICROENCAPSULATION
Rick Rehrig, Harper International, West Drullard Avenue, Lancaster, NY
14086; rrehrig@harperintl.com
162
The majority of commercially available raw materials is sold as grains, flakes, blocks or
powders. This granulometries have many disadvantages. Particularly the handling of active
agents becomes difficult. In addition to possible instabilities of the active agent in air, one
might need expensive equipment to dose potent expensive agents or to handle oily ones.
BRACE microspheres and microcapsules can solve these problems. Microspheres are solid
spheres with a matrix-encapsulated active agent whereas Microcapsules consist of a solid
shell and a liquid or solidified core. The major difference between these two types of
microgranules is the different release profiles of microspheres and microcapsules.
Microspheres usually have diffusion controlled release profiles with a permanent release
rate that is controlled kinetically by the particle size, whereas microcapsules expel their
content by a single high burst as the shell breaks or (with special shell materials) extremely
slow releases. The patented BRACE-processes for the production of microspheres and
microcapsules are basically vibrating nozzle processes. With these processes it is possible
to produce particles with a monomodal grain size distribution with a single sharp
maximum. dmax/dmin- values lower than 1.10, 1.05 or even 1.01 are customary for spherical
granules produced with a microsphere unit designed by BRACE. With these units, it is
possible to obtain microspheres or microcapsules with a diameter range of 50 to 6000 µm.
For the production of particles smaller or larger than that, BRACE manufactures special
nozzles. A wide range of shell materials can be used in this highly scalable process. Tests
have shown that the vibrating nozzle processes (laminar flow break-up) scale very well
with Newtonian liquids. For industrial applications, it is possible to use multi-nozzle
systems as well as high throughput settings.
C2 – Contributed Paper
ON THE SYNTHESIS AND CHARACTERIZATION OF
BIODEGRADABLE DEXTRAN NANOGELS WITH TUNABLE
DEGRADATION PROPERTIES
T.G. Van Thienen1, B. Lucas1, J. Demeester and S.C. De Smedt1 Laboratory
of General Biochemistry and Physical Pharmacy, Department of
Pharmaceutics, University Ghent, Harelbekestraat 72, B-9000 Ghent, Belgium;
tinneke.vanthienen@ugent.be
163
Hydrogels are widely investigated as carriers in drug delivery. To be suitable carriers for
intracellular drug delivery the hydrogels should be small enough to be able to enter cells.
This presentation reports on the synthesis and characterization of both lipid coated and
‘naked’ biodegradable hydroxyethylmethacrylated dextran (dex-HEMA) nanogels.
Dynamic Light Scattering (DLS), atomic force microscopy and transmission electron
microscopy showed that lipid coated nanogels could be obtained by polymerization of an
aqueous dex-HEMA solution entrapped in SOPC:DOTAP liposomes (SOPC and DOTAP
139
Oral Abstracts
respectively being 1-stearoyl-sn-glycero-3-phosphocholine and
1,2-dioleolyl-3-trimethylamonium propane chloride). Naked dex-HEMA nanogels were
prepared by removing the lipid coating by Triton X 100. DLS measurements on
dex-HEMA nanogels stored in buffer at 37 °C revealed that the degradation time depended
on the cross-link density of the nanogels: dex-HEMA nanogel prepared from dextran lowly
substituted with HEMA degraded fast while it took days to weeks for nanogels prepared
from highly substituted dextran. Furthermore, confocal laser scanning microscopy showed
that SOPC:DOTAP coated dex-HEMA nanogels can be taken up by VERO-1 cells.
D4 – Invited Paper
LUIDIC FORCE DISCRIMINATION ASSAYS IN COMPLEX MEDIA
hawn P. Mulvaney, Alison A. Glaser, Matthew D. Kniller, Michael Malito, Jack
fe, Monica W. Stanton, Cy R. Tamanaha, and Lloyd Whitman, Naval Research
aboratory, Code 6177: Surface Nanoscience and Sensor Technology, Washington
C. 20375, USA; shawn.mulvaney@nrl.navy.mil
164
The Naval Research Laboratory’s compact Bead Array Sensor System (cBASS™) is under
advanced development for multiplexed detection of pathogens and toxins in environmental
and clinical samples. The portable cBASS™ prototype includes a suite of patented and
patent-pending technologies for microfluidic, microbead-based microarray assays
performed on a Bead ARray Counter (BARC®) sensor chip. There are two core aspects of
the system: a Fluidic Force Discrimination™ (FFD) assay, whereby biomolecular targets
are captured onto a microarray, labeled with microbeads, and nonspecifically bound bead
labels are removed by controlled fluidic forces; and a detection system, whereby the
number of microbead labels on each microarray element is counted. In cBASS™, detection
of captured labels is performed directly by a BARC® sensor chip in a disposable cartridge.
For higher throughput applications, labels can be counted optically in a multi-channel,
slide-based system that mounts on a standard upright microscope. Highly sensitive DNA
assays (<10 fM) and immunoassays (<1 ng/mL) have been demonstrated in less than 30
minutes at room temperature, without amplification or concentration steps (i.e. PCR).
Successful assays have also been run in serum, plasma, whole blood, and complex
environmental matrices. The technology is being commercialized in collaboration with
Seahawk Biosystems (www.seahawkbio.com). S.P.M., A.A.G., M.D.K. M.M, and
M.W.S. are employees of Nova Research Inc., Alexandria, Va.
D4 – Invited Paper
MAGNETIC BEADS USED IN SAMPLE PREPARATION FOR MASS
SPECTROMETRY
Geir Fonnum, Thuy Diem Thi Tran, Kristine Evensen, David Gillooly,
Elizabeth Breivold, Marie Bosnes. Dynal, Invitrogen Corporation.
Ullernchausèen 52, N-309 Oslo, Norway; geir.fonnum@invitrogen.com
165
140
Oral Abstracts
The use of magnetic beads in sample preparation is now a standard technique that enables
the use of highly automated systems and opens up the possibilities of high throughput. The
demand for both beads with higher protein/peptide capacity and shorter separations times
lead to the development of new one micron magnetic beads. This bead type was
characterized by magnetic measurements and compared to Dynabeads® of different
diameters showing the relation between maghemite content, size and separation time.
Identification of disease-specific protein and/or peptide biomarkers in body fluids is used
to detect and diagnose disease and allow the assessment of disease severity, progression,
and the effectiveness of treatments. Mass spectrometry (MS) is the analytical method of
choice for biomarker discovery whereby protein and/or peptide profiles need to be
obtained from large sample numbers. The complex nature of biological fluids, dynamic
range constraints associated with MS, and the sensitivity of MS to salts and detergents
means that reproducible sample preparation procedures reducing sample complexity and
removing contaminants are required. We have developed a set of ion exchange and
reversed phase magnetic beads based on one micron magnetic beads for this purpose.
Weak and strong ion exchange magnetic beads can be used to fractionate complex
mixtures of proteins, consequently increasing the amount of information that can be
obtained from these samples. Reversed phase chromatography (RPC) magnetic beads have
been developed for the fractionation, desalting and concentration of protein and peptide
mixtures. We have data that shows that samples containing salts and contaminants that
prevented the attainment of MS spectra could be used to obtain excellent MS spectra after
using simple automatable experimental protocols involving RPC magnetic beads. Studies
of different types of hydrophobic groups on the surface of RPC beads will be discussed.
D4 – Contributed Paper
MAGNETO-RESISTIVE IMMUNOSENSORS: SENSITIVITY
ENHANCEMENT BY ACTIVE GUIDING OF SUPERPARAMAGNETIC
PARTICLES
R. Wirix-Speetjens, G. Reekmans, R. De Palma, C. Liu, W. Laureyn and
G. Borghs, Interuniversity MicroElectronics Center (IMEC), MCP-ART,
Kapeldreef 75, B-3001 Heverlee, Belgium; Wim.Laureyn@imec.be
166
Microelectronics-based biosensors are increasingly gaining importance since they offer a
number of advantages such as small size, fast in use, simplicity in operation, and eventually
low cost. However, increasing the device sensitivity remains a challenging task in
biosensor development. Magnetic biosensors are a suitable candidate for highly sensitive
bio-sensing. In this approach, the classical label (e.g. fluorescent) is replaced by a
super-paramagnetic particle, which can be detected using e.g. magneto-resistive sensors.
The pioneering work in the field of magneto-resistive biosensors was performed by the
Naval Research Laboratory followed by others which are mainly aiming at the detection of
DNA hybridization. Previously, we have demonstrated the controlled manipulation of
magnetic particles using integrated current conductors. In this paper, we report on the
development of magneto-resistive biosensors (i.e. spin-valves) with the aim to increase the
sensitivity by combining detection and manipulation of magnetic particles. For
141
Oral Abstracts
magneto-resistive sensors, the position of bound magnetic particles relative to the sensor
location shows a clear dependence on the signal. Based on this phenomenon, we are
exploring the ability to enhance the sensitivity and specificity via active guiding of
magnetic particles using on-chip generated magnetic forces. First, a sandwich assay is
build up on the device surface, followed by labeling with magnetic particles. Then, the
bound magnetic particles are released and transported to that position that theoretically
gives rise to the maximal signal, ensuring the most sensitive detection. Next to the
development of this alternative detection mechanism, the impact of the surface chemistry,
assay, type of particles and release mechanism has been fully evaluated in order to enhance
the sensitivity, specificity and dynamic range for the detection of proteins. Currently, the
detection of S100ββ, a marker for ischemic stroke (and brain damage in general), is being
targeted.
D4 – Contributed Paper
167
ENCAPSULATED MICROCRYSTALLINE PARTICLES AS LABEL
SYSTEMS FOR DIAGNOSTIS
Wing Cheung Mak 1, Kwan Yee Ceung 1, Reinhard Renneberg 2 and Dieter
Trau 1, 1Division of Bioengineering, NanoBioanalytics Laboratory, National
University of Singapore, 9 Engineering Drive 1, Singapore 117576;
2
Department of Chemistry and Sino-German Nano-Analytical Laboratory,
Hong Kong University of Science and Technology, Clear Water Bay,
Kowloon, Hong Kong; biemwc@nus.edu.sg
A novel class of biolabel system based on encapsulated organic microcrystalline particles
was introduced. The significant of organic microcrystal biolabels compared with other
particulate label systems is the dissolution property of the organic microcrystals upon
exposure to a desired solvent which leads to the release of a large number of
signal-generating molecules (~ 107 to 109 molecules per microcrystal); termed as the
“Supernova Effect”. We have demonstrated various applications of encapsulated organic
microcrystalline particle biolabels in diagnostics by utilizing organic microcrystalline
particles with different properties such as electrochemical-active organic microparticles
for silver enhancement or electrochemical immunoassay; fluorogenic precursor organic
microparticles for fluorescence immunoassay and silole microparticles for
aggregation-induction emission assay. Our biolabel technology provides a new strategy for
biolabelling over the traditional enzyme-based, fluorescence-based and particle-based
biolabel system. The technology for preparing organic microcrystalline particles biolabels
and different strategies for utilizing encapsulated microcrystalline particles for diagnostics
will be presented.
D4 – Invited Paper
CHIP-BASED MOLECULAR DIAGNOSTICS USING METAL
NANOPARTICLES
Wolfgang Fritzsche, Robert Möller, Grit Festag, Thomas Schüler, Andrea
Steinbrück, Andrea Csáki, Institute for Physical High Technology (IPHT),
168
142
Oral Abstracts
Photonic Chip Systems Dep. A.-Einstein-Str. 9, 07745 Jena,
fritzsche@ipht-jena.de
Metal nanoparticles represent an interesting alternative as marker in molecular diagnostics.
High stability and straightforward signal detection are possible when such particle labels
are combined with enhancement techniques based on specific metal deposition. Light
scattering at the (enhanced) particles is a simple and robust approach for microarray
detection, and examples for easy readout as well as detection at the single particle level by
standard means will be presented. The formation of metal layer around the original particle
leads to a metal film at the substrate surface. This film could be detected by measurements
of the electrical resistance along the surface. A system based on microstructured electrodes
and a dedicated electrical chip reader will be presented. Problems related to the precise
positioning of the capture DNA on such chips as well as to corresponding alternative,
cost-efficient substrates were studied. Another field for investigations is the utilization of
alternative approaches for metal enhancement. The performance of this enhancement is a
key factor for the sensitivity of the method because the non-specific deposition of metal
seeds determines the background level. An enzymatic system was studied that allows for a
high performance electrical DNA chip detection and was successfully demonstrated for the
identification of microorganisms from PCR samples.
D4 – Contributed Paper
HYBRID PARTICLES AS SUBSTRATES FOR BIOTARGETS AND
METALIC IONS
L. B. R. Castro, A.M. Carmona-Ribeiro and D.F.S. Petri. Instituto de Química,
Universidade de São Paulo, Brazil; dfsp@usp.br
169
The synthesis of hybrid particles was carried out by emulsion polymerization of styrene in
complexes formed by carboxymethyl cellulose (CMC), a polyanion, and a cationic
surfactant, cetyltrimethylammonium bromide (CTAB). CMC chains with variable
molecular weight and degree of substitution were tested. The polymerization condition
chosen was that corresponding to CMC chains fully saturated with CTAB and to the onset
of pure surfactant micelles formation, namely at the critical aggregation concentration. The
hybrid particles were characterized by zeta potential and light scattering measurements.
The period of colloidal stability stable in the ionic strength of 2.0 mol L-1 NaCl was
observed visually. Upon increasing the CMC chain length, the particle characteristics
remained practically unchanged, but the colloid stability was increased. The increase in the
CMC degree of substitution led to particles with more negative zeta potential values. The
adsorption of biotargets as concanavalinA (ConA) and hexokinase (HK), as well as of
copper ions (Cu2+) on the surface of hybrid particles could be well described by the
adsorption models. These results evidenced the potential of such hybrid particles for
biotechnological applications.
143
Oral Abstracts
D4 – Invited Paper
ASSEMBLY AND IN-VIVO TRACKING OF NANOPARTICULATE
CARRIERS FOR NEO-VASCULAR TARGETING
Heinrich Haas, John Nieland, MediGene AG., Lochhamer Str. 11, D-82152
Martinsried, Germany, Leide Cavalcanti, Oleg Konovalov, Stephanie Corde,
Thierry Brochart, Geraldine Le Duc, ESRF, Grenoble; h.haas@medigene.com
170
In a new approach for targeted drug delivery, cationic nanoparticulate carriers are used for
delivery of pharmaceutical compounds to activated (angiogenic) endothelial cells. Because
angiogenesis is a key issue in a variety of pathological situations, like tumor growth or in
inflammatory diseases, cationic vascular targeting provides new, alternative, options for
treatment in those cases. In this context Medigene AG (www.medigene.com) is developing
cationic liposome products (EndoTAG) for tumor therapy and diagnostics. For rational
development of such novel drug delivery systems, parameters like molecular composition,
drug load and organization on the molecular and mesoscopic scale must be correlated with
the targeting characteristics in vivo. Here, results from physico-chemical characterization
and from in vivo tracking of lipid-based carriers are given. X-ray scattering and
spectroscopic techniques have been used to study drug loading to the lipid carrier matrix.
For tracking of the distribution of the colloidal carriers in vivo, Monochromatic
Quantitative Computed Tomography (MQCT) at the European Synchrotron Radiation
Facility (www.esrf.fr) has been used. The method provides in vivo absolute concentration
maps of contrast agents with good temporal (few seconds) and spatial resolution (350 μm),
and it has been highlighted as a complementary tool to other imaging techniques in the
field of preclinical and contrast medium research. After injection of several types of
Gd-based liposomes in the rats bearing a 9L glioma, the Gd concentrations in the brain
were mapped as a function of time. Different concentration profiles in the blood were
found for Gd-loaded liposomes and free Gd. Specific patterns for tumor accumulation of
cationic liposomes were found. The correlation between the molecular setup of the
liposomes and the targeting characteristics was revealed. The data demonstrate, that in
vivo tracking, such as by MQCT, can be a useful tool for screening and optimizing of
colloidal drug delivery systems.
D4 – Contributed Paper
TUNING OF LUMINESCENCE INTENSITY OF MANGANESE DOPED
CADMIUM SULFIDE QUANTUM DOTS BY CONTROLLING SURFACE
PASSIVATION
Subir K. Sabui, Swadeshmukul Santra, Nanoscience Technology Center,
Department of Chemistry and Biomolecular Science Center, University of
Central Florida, 12424 Research Parkway, Suite 400, Research Pavilion,
Orlando, FL 32826; ssantra@mail.ucf.edu
171
Brightness of manganese doped cadmium sulfide (CdS:Mn) quantum dot nanocryatals
(~3.0 nm) depends on how well the nanocrystal surface is passivated. A coating of 1-2
atomic layer thick ZnS (a wide bandgap material) has shown to be effective to passivate
144
Oral Abstracts
CdS:Mn surface completely and minimize surface defects. As a result, highly bright
yellow emission of CdS:Mn/ZnS is obtained and the emission remains insensitive to the
environment. In this study, we have developed a unique synthesis protocol that allows
synthesis of CdS:Mn nanocrystals at varoius extent of surface passivation with ZnS layer.
As a result of partial surface passivation, this material behaves as if the emission is
internally quenched. The present study showed that partially passivated Cd:Mn/ZnS
nanocrystals are highly sensitive to the external environment. The solvatochromism and
spectroscopic characteristics of partially passivated CdS:Mn/ZnS nanocrystals are
thoroughly described. We believe that this study will initiate research in using quantum
dots as optical based sensors.
D4 – Contributed Paper
SINGLE-PARTICLE BIOAEROSOL MASS SPECTROMETRY FOR
MEDICAL AND BIOCHEMICAL DIAGNOSTIC AND ANALYSIS
Matthias Frank, Michael Bogan, Keith R. Coffee, George Farquar, David P.
Fergenson, Eric E. Gard, , Sue I. Martin, , Vincent J. Riot, Urs Rohner, Paul T.
Steele, Herb J. Tobias, Lawrence Livermore National Laboratory, Livermore
CA 94551, USA; frank1@llnl.gov; Erica L. McJimpsey, Carlito Lebrilla,
University of California Davis, Davis CA 95616, USA
172
We are developing a single-particle bioaerosol mass spectrometry (BAMS) system that can
rapidly analyze individual biological particles in the size range from 500nm to 10 μm (e.g.
bacteria, bacterial spores, clumps of viruses, liposomes) that are sampled from a nebulizer
or directly from air into a time-of-flight mass spectrometer. An individial incoming particle
is tracked and sized by laser light scattering and probed by UV-fluorescence before a short
energetic pulse from a desorption/ionization laser vaporizes the particles and creates
characteristic molecular ions characteristic for the biochemical composition of the particle.
Mass spectra from both positive and negative ions created by matrix-free or
matrix-assisted laser desorption and ionization are recorded simultaneously and can be
analyzed and classified in real-time. At present, tens of particles can be analyzed per
second this way. Using the characteristic mass spectra from individual biological particles
our system is capable of discriminating, particle by particle and in real time, between
bacterial spores, vegetative cells and other biological and non-biological background
materials using the mass fingerprints obtained from those particles. In addition, selected
species of bacteria can be discriminated from each other with this method. Here we will
present the first results from exploring applying this technique to the rapid analysis and
screening of human effluents, such as exhaled aerosol or re-aerosolized breath condensate,
for the detection and diagnosis of respiratory disease. Other applications of this BAMS
technique may include the high throughput characterization and quality control of aerosol
particles that are used for drug delivery. This work was performed under the auspices of
U.S. DOE by University of California Lawrence Livermore National Laboratory under
contract No. W-7405-ENG-48.
145
Oral Abstracts
I2 – Keynote Paper
DENDRIMERS, DENDRONS, DENDRISOMES AND DENDRIPLEXES
AS CARRIERS IN DRUG AND GENE DELIVERY
A. T. Florence, K. Al-Jamal, C. Ramaswamy, P. Ruenraroengsak, S. Ribeiro,
B. Singh, The School of Pharmacy, University of London, 29/39 Brunswick
Square, London WC1N 1AX, United Kingdom; a.t.florence@ulsop.ac.uk
173
Dendrimers are the irreducibly small units that have been studied increasing widely as
carriers for drugs, genes and other macromolecules. Irreducibly small because the
molecular radius of many therapeutic agents is greater or similar to that of generations that
can be produced in monodisperse form. However, the small diameter of dendrimers allows
them certain advantages in diffusion and transport in tissue to deliver their load. There are
at least two reasons why dendrimers can be useful in spite of the low carrying capacity for
many molecules. The first is that multiple dendrimers associate with macromolecules such
as DNA and heparin, a process often electrostatically driven, so that compact complexes
are formed which have the ability to be taken up into cells. Secondly dendrimers with
appropriate disposition of hydrophobic and hydrophilic geometry can associate to form
larger structures, dendrisomes (vesicle-like forms) or into nanoparticles, two of the
systems we have studied. Dendrimers which have been complexed with DNA to form
dendriplexes, can be incorporated into PLGA nanoparticles to provide a slow release
system which would not be possible with the dendrimer construct itself. Dendrimers are
thus versatile building blocks for the exploration of means of enhancing drug, gene and
vaccine delivery. Although products are beginning to reach the clinic, there are still
obstacles to overcome. These include control of drug release often rapid due to the large
dendrimer surface area, the ability of these colloidal particles to flocculate and aggregate;
nonetheless the ability of dendrimers to diffuse into cells and experience lesser obstruction
in the crowded cell interiors than larger nanoparticles must be an advantage. Data on
dendron (partial dendrimer) and dendron behaviour in vitro and in vivo will be discussed in
this survey of where we are and how dendrimers are shaping up to be a superior alternative
to nanoparticulate delivery vectors.
I2 – Invited Paper
DENDRIMERS: A PLATFORM FOR CUSTOM-DESIGNED DRUG
DELIVERY
Sonke Svenson, A.S. Chauhan, L.A. Reyna, D.A., Tomalia, Dendritic
NanoTechnologies, Inc., Mount Pleasant, MI, 48858, USA;
svenson@dnanotech.com
174
Many potential drugs and launched products suffer from low bioavailability due to poor
water solubility or membrane permeability. Drug carriers can improve solubility and
permeability, and can provide the option of targeted delivery, i.e., passive targeting
through size exclusion (EPR Effect) or active targeting through ligands that interact with
receptors over-expressed on tumor cell surfaces (e.g. folic acid interacting with the high
affinity folate receptor). Successful drug carriers should also reduce the cytotoxicity of an
146
Oral Abstracts
encapsulated drug. Poly(amidoamine) (PAMAM) STARBURST® dendrimers are a class
of core-shell nanostructures with precise architecture and low polydispersity, which are
synthesized in a layer-by-layer fashion around a core unit, resulting in a high level of
control over size, branching points and surface functionality. This control over dendrimer
architecture, and the resulting ability to tailor dendrimers to the needs of a drug, makes
them ideal carriers for drug delivery applications, as exemplarily shown using the
anti-cancer drug cisplatin and the non-steroidal anti-inflammatory drug (NSAID)
indomethacin. Both drugs have been encapsulated into STARBURST® dendrimers, and
their encapsulation efficiency and release profiles in DI water and PBS at pH 7.2 have been
studied. Cisplatin encapsulation was successful using dendrimers with carboxylate
surface. Dendrimer size (generations 3.5 or 4.5) and size of the core molecule (C2, C4, or
C12) had little effect on the encapsulation efficiency. The release profiles in DI water and
PBS revealed a two-step process, burst release over 30 minutes, followed by sustained
release over several hours. The release in PBS was shifted to slightly higher percentages
due to its higher ionic strength. Indomethatcin encapsulation was successful in dendrimers
with amino (NH2), hydroxy (OH) and carboxylate (COO-) surfaces, with NH2>OH>COO-.
The encapsulation efficiency increased with dendrimer size; however, the core size (C2 vs.
C12) had little effect. The release profiles were dependent on surface groups
(NH2<OH<COO-), dendrimer size (G3>G4>G5>G6) and size of the core molecule
(C2>C12). For both drugs, encapsulation enhanced their water solubility by orders of
magnitude. The cytotoxicity of cisplatin was greatly reduced through its encapsulation, as
shown on several cell lines. STARBURST® dendrimers are a versatile platform that can be
tailored to the needs of a drug to achieve the desired drug encapsulation efficiency and
release profile.
I2 – Invited Paper
WHAT CONSTITUTES A PARTICLE? ASSEMBLY OF 30-500 NM
DENDRITIC (FRACTAL) HYPERPOLYMERS VIA SEQUENCE
RECOGNITION ENABLED POLYMERS
Thor W. Nilsen, Genisphere, Hatfield, PA 19440, USA;
Thor_Nilsen@Datascope.com
175
Dendritic “particles” have the characteristic of presenting a “surface” with a maximum
number of reactive moieties with a minimum number of structural elements. Sequence
recognition, such as that exhibited by nucleic acids and nucleic acid like polymers, is an
optimal starting point for the assembly of molecular networks. The ability of a linear
polymer to “recognize” a cognate polymer sequence is the underlying principle. A
polymer with linear recognition elements, such as DNA, can be used to assemble 3-D
structures with defined characteristics. We present the assembly and characterization of
molecules of 300Å to 4200 Å (MW 70,000 Æ 12,000,000). We further present the
application of these molecular constructs for amplification of signal to the single molecule
detection limit and assembly of molecular capture networks in chromatography
applications.
147
Oral Abstracts
I2 – Invited Paper
FUNCTIONALIZED MESOPOROUS SILICA NANOPARTICLES FOR
GENE TRANSFER, INTRACELLULAR CONTROLLED RELEASE, AND
BIOSENSOR APPLICATIONS
Victor S.-Y. Lin, Department of Chemistry, US DOE Ames Laboratory, Iowa
State University, Ames, IA 50011-3111, USA; vsylin@iastate.edu
176
We have recently synthesized a series of multi-functionalized, MCM-41 type mesoporous
silica nanosphere (MSN) materials. The mesopore surface of these materials was
derivatized with fluorescence sensor groups that could recognize and react with amino
acid-based neurotransmitters. The exterior surface of the MSN materials was covalently
coated with polylactides or polypeptides. By utilizing the polylactide (PLA) or
polypeptide layer as gatekeepers to regulate the rates of diffusion of several structurally
similar neurotransmitters, such as dopamine, tyrosine, and glutamic acid, into the sensor
mesopores, a highly selective fluorescence biosensor that could distinguish dopamine from
glutamic acid under physiological condition was synthesized. These MSN materials were
also designed as a stimuli-responsive controlled release delivery system. Several
pharmaceutical drugs and neurotransmitters were encapsulated inside the mesopores of
MSN by capping the openings of the mesopores with various chemically removable caps,
such as surface-derivatized cadmium sulfide (CdS) nanocrystals, superparamagnetic iron
oxide nanoparticles (Fe3O4), and cell membrane permeable dendrimers, e.g.
polyamidoamine (PAMAM) dendrimer, to block the molecules of interest from leaching
out. We studied the stimuli-responsive release profiles of several
drug/neurotransmitter-loaded MSN systems by using various non-cytotoxic chemicals as
release triggers. Furthermore, the gene transfection efficacy, uptake mechanism, and
biocompatibility of the capped-MSN system with various cell types, such as neural glia
(astrocytes), human cervical cancer (HeLa), and Chinese hamster ovarian (CHO) cells
were investigated. The mesoporous structure of the MSN material allows membrane
impermeable molecules, such as pharmaceutical drugs and fluorescent dyes, to be
encapsulated inside the MSN channels. We envision that these MSNs can serve as a
universal transmembrane carrier for intracellular drug/gene delivery and imaging
applications.
I2 – Invited Paper
A STANDARDIZED PROCEDURE FOR DERIVATIZATION OF
NANOPARTICLES WITH FUNCTIONALLY ACTIVE PROTEINS
Marina V. Backer*, Achintya K. Bandyopadhyaya† , B.T.S. Thirumamagal† ,
Werner Tjarks† , Rolf F. Barth**, and Joseph M. Backer*, *SibTech, Inc.,
Newington, CT 06111, † College of Pharmacy, The Ohio State University,
Columbus, OH, 43210, and **Department of Pathology, The Ohio State
University, Columbus, OH, 43210, USA. jbacker@sibtech.com
177
We have developed a robust platform technology for facile and uniform derivatization of
nanoparticles with functionally active proteins. This technology is based on a novel 15-aa
humanized, cysteine-containing tag, named C-tag, that contains a unique cysteine residue
for site-specific conjugation via thiol-directed chemistries. We found that in a variety of
148
Oral Abstracts
proteins expressed with C-tag, a cysteine residue in C-tag can be modified with different
payloads without affecting protein functional activity. To validate this platform, C-tag was
fused to either N- or C-termini of several proteins, expressed in bacteria, refolded under
red-ox conditions, purified, and site-specifically conjugated to various payloads, such as
dendrimers, quantum dots, liposomes. In all cases, functional activities of loaded proteins
tested in vitro and in vivo were similar to that of free proteins. In a specific example,
C-tagged vascular endothelial growth factor (VEGF) was conjugated to nanoparticles that
combine therapeutic and diagnostic components for targeted treatment and imaging of
tumor vasculature. These “theranostic” nanoparticles were constructed on the basis of 5th
generation of PAMAM dendrimers that were derivatized with 105-110 decaborate
(Na(CH3)3NB10H8NCO) for boron neutron capture therapy and with Cy5-dye for
near-infrared fluorescent imaging in vivo. Derivatized nanoparticles were conjugated
site-specifically to C-tagged VEGF via a bi-functional crosslinker sulfo-LC-SPDP. VEGF
on the surface of the theranostic nanoparticle retained functional activity in tissue culture
assays and provided for imageable accumulation of nanoparticles in endothelial cells of
tumor vasculature in mouse models. We expect that the use of C-tagged proteins would
provide for rapid, facile and reliable method for coupling functional proteins to
nanoparticles.
I2 – Invited Paper
BRANCHED NANOPARTICLES FOR DRUG DELIVERY ACROSS THE
BLOOD BRAIN BARRIER
Eun S. Gil,1 Young S. Kim,2 Annie Mitsak,3 Jianshu Li,3 Huining Xiao3 and
Tao L. Lowe1,2,3, Departments of Surgery,1 Bioengineering,2 Biomaterials and
Bionanotechnology Summer Institute,3 and Materials Science and
Engineering,4 Pennsylvania State University, 500 University Drive, Hershey,
Pennsylvania 17033, U.S.A.; 3Department of Chemical Engineering,
University of New Brunswick, Fredericton, NB, Canada E3B 5A3;
tlowe@psu.edu
178
The blood-brain barrier (BBB) is a dynamic and complex structure composed principally
of specialized capillary endothelial cells held together by highly restrictive tight junctions.
It allows the passage of nutrients into the brain, while preventing the passage of many
substances, posing a problem for cerebral drug delivery from the blood stream. In this
work, we have developed branched nanoparticles including thermo-responsive and
biodegradable dendrimers and beta-cyclodextrin for controlled drug delivery across the
BBB. The effects of the nanoparticles on the integrity of bovine blood brain endothelial
cell (BREC) and bovine retinal brain endothelial cell monolayers, in vitro BBB models,
were studied. The permeability of the nanoparticles with/without model protein drugs,
bovine serum albumin (BSA) and nerve growth factor (NGF), through the BBB models, is
also investigated. Completion of this project will have significant impact on the treatments
of neurological disorders in the brain.
149
Oral Abstracts
N1 – Keynote Paper
NANOSUSPENSIONS FOR DELIVERY OF POORLY SOLUBLE DRUGS:
STATE OF THE ART AND LATEST DEVELOPMENTS
Rainer H. Müller 1, 2 and Jan Möschwitzer1; 1Free University of Berlin,
Department of Pharmacy, Kelchstrasse 31, 12169 Berlin, Germany;
2
PharmaSol GmbH, Blohmstrasse 66a, 12307 Berlin, Germany;
info@pharmaso.biz
179
The number of drugs being poorly soluble is steadingly increasing. About 10% of the drugs
in the development pipelines are poorly soluble, even up to 60% of compounds coming
directly from chemical synthesis. Very often, the poor solubility is correlated with a poor
oral bioavailability. Intravenous injection as alternative is not possible because of the too
large injection volumes required due to the poor solubility. Therefore there is a definite need
for smart technological formulation approaches to overcome the problem of poor oral
bioavailability and/or provide formulations suitable for intravenous injections. Ideally such
a formulation approach should be universally applicable to any drug. Such an universal
formulation approach applicable to almost any drug is “nanonization”. The drug powder is
transferred to drug nanocrystals, typically by wet milling processes leading to drug
nanocrystals suspended in a liquid dispersion medium, the so called nanosuspension. The
“makeability” of drug nanocrystals for pharmaceutical formulations has been proven by the
first products introduced to the pharmaceutical marked. Drug nanocrystals can be produced
by “bottom up” or “top down” technologies. Industrially most relevant are the top down
technologies, that means production of drug nanosuspensions by pearl milling or by high
pressure homogenization. The high pressure homogenization can be performed either
having the drug particles dispersed in water or alternatively using non-aqueous or
water-reduced media. Production of drug nanocrystals in liquid or solid polyethylene glycols
(PEGs) has the advantage that these suspensions can directly be filled into capsules for oral
delivery. It is also possible to combine bottom up and top down technology, that means
preparing a fine drug suspension by precipitation (adding solvent to non-solvent) and
subsequently applying a high energy step such as high pressure homogenisation
(NANOEDGE technology). A clear disadvantage of using precipitation is the need for
solvent removal (at least in most cases) and the problem of solvent residues, in addition
making the process costly. The special feature of the drug nanocrystals is an increased
surface area but also an increased saturation solubility of the poorly soluble drugs. This leads
to a distinctly enhanced dissolution velocity, thus reaching a sufficiently high oral bio
availability in case the dissolution velocity is the absorption limiting step. In addition,
nanosuspensions can be injected intravenously as highly concentrated suspensions.
Saturation solubility and dissolution velocity increase with decreasing particle size.
Therefore to obtain extremely fast dissolving particles with a very high saturation solubility,
it would be desirable to have particles with a size of about 100nm or even distinctly less.
Therefore one present trend is to produce drug nanocrystals of 100nm or below. In addition,
there is a clear demand for shortening the production time. Pearl milling requires hours to
days, high pressure homogenisation typically 10 to 20 homogenization cycles. Drug
nanocrystals dissolve fast, however for certain oral applications it is desirable to have a
delayed release or a prolonged / sustained release. Therefore technologies are required to
150
Oral Abstracts
modify drug dissolution from drug nanocrystals during transit of the gastrointestinal tract. In
high pressure homogenization, the number of homogenization cycles could be reduced by
50% or more by applying a special pre-treatment step in drug synthesis before the obtained
powder is processed as suspension by high pressure homogenisation (so called “H42
technology”). In some cases drug nanosuspensions can be obtained with only a few
homogenisation cycles. Nanocrystals below 100nm could be produced applying a
precipitation method under special conditions (H69 technology) or alternatively again by
high pressure homogenization using an especially pre-treated drug powder (H96
technology). To protect the produced drug nanocrystals against the acidic environment of
the stomach, a coating process was developed for the coating of the single nanocrystals
without the need of organic solvents [6]. For controlled release in the gut, various Eudragit
polymers were applied for the production of different types of pellet systems. This allows to
adapt the release and dissolution profile of the nanocrystals to obtain optimal blood levels
for the treatment.
N1 – Invited Paper
NANOSUSPENSIONS OF POORLY SOLUBLE ACTIVE INGREDIENTS
Ingrid Fischbach, Jens Rieger, BASG-AG, GVC/F – J542; Ludwigshafen
67056, Germany; ingrid.fischbach@basf.com
180
Many organic active ingredients exhibit poor solubilities in both aqueous media and
organic solvents. This represents a severe problem to the formulator, since low solubilities
make it very difficult to produce formulations with high bioavailabilities. Nanoparticulate
formulations are of particular interest for such actives, since particle sizes in the range of
50 – 500 nm go along with a dramatic increase in solubility, enhancement of the biological
resorption and the modification of optical, electrooptical and other properties. Such
ultrafine dispersions can be obtained from a solution of the active via controlled
precipitation. Interfacial activity and colloidal stability is achieved by additional excipients
(surfactants, polymers). The mode of action of polymeric excipients for the control of
crystallization and for the stabilization of ultrafine dispersions will be discussed in detail
considering some selected examples.
N1 – Contributed Paper
SIZE CONTROL OF NANOPARTICLES IN CONTINUOUS
CRYSTALLIZATIONS: SOLUBILITY EFFECT
Ingo H. Leubner, Crystallization Consulting, 35 Hillcrest Drive, Penfield, NY
14526-2411, USA, ileubner@crystallizationcon.com
181
Continuous crystallization is an attractive method for large scale preparation of crystalline
materials. To control the crystal size of the product it is desirable to have a theory based on
fundamental science that allows simple modeling and accurate predictions. The balanced
nucleation and growth (BNG) theory predicts the size dependence as a function of
experimentally controlled parameters. In the present work, the predicted size dependence
on solubility is experimentally supported for continuous crystallization in the CSTR
151
Oral Abstracts
(MSMPR) crystallizers. As a model system, silver chloride was chosen where the
solubility was varied from 0.81 to 8.3E-04 mole/l (60 C and 3.0 min residence time). The
average crystal size varied from 380 to 580 nm. The model and experimental results allow
to determine all parameters to predict crystal sizes, and to obtain fundamental
understanding of the critical processes. Combining model and experiments, the maximum
growth rate of the crystals at steady state, Gm, was determined to 0.96 nm/s, and the ratio of
critical to average crystal size to 0.79. The supersaturation at steady state was determined
to 1.0029 (+/-0.0004). The prediction, that the average crystal size is independent of
reactant addition rate and of suspension density, was experimentally confirmed. Since the
model is based on fundamental science, it is generally applicable to all crystalline systems.
N1 – Invited Paper
APPLICATIONS OF NANOTECHNOLOGY IN THE PHARMA
INDUSTRY – AN OVERVIEW
Hemant N. Joshi, Spectrum Pharmaceuticals, Inc., 157, Technology Drive,
Irvine, CA 92618, USA; hjoshi@spectrumpharm.com
182
Nanotechnology is the latest buzz-word in our lives. As the word indicates, nano is less
than micro and nanoparticles can not be seen by naked eyes. Nanotechnolgy has been part
of the pharma industry for the last couple of decades. However, the real applications are
being studied in now in more recent times. Nanotechnology is playing a prominent role in
other industries too. Terms such as nanocrystals, nanotubes, nanoparticles, etc. are
becoming common terms in the pharma industry. However, the word nano is still rather
loosely used in the pharma industry. It is important to take into consideration the
“effective” particle size rather than the individual particle size in ascertaining the particles
in the system as nanoparticles. This paper will define the term and set the stage for
presentations to follow. Nanoparticles can increase the surface area for solubilization, but
true nanoparticles (less than 200 nm) can also form very stable suspensions which can be
delivered intravenously. The real achievement for nanotechnology is the targetted delivery
of drugs to cell components where the drug treatment is needed. Nanotechnology provides
potential promises, but it is certainly not without problems. Nanoparticles can enter our
body via the GI tract, skin and lungs. Key applications of the technology and potential
problems are discussed. Nanoparticles may pose risks to the professionals manufacturing
the products, and those who are handling the formulations.
N1 –Contributed Paper
ELECTROSTATIC INTERACTIONS BETWEEN LYSOZYME AND
POLY(ACRYLIC ACID) MICROGEL PARTICLES
Christian Johansson, Martin Malmsten, Department of Pharmacy, Uppsala
University, Sweden; Christian.Johansson@farmaci.uu.se
183
Microgel particles are polymer networks that swell/deswell as a response to changes in the
environment. As a model for studying electrostatic interactions between protein drugs and
152
Oral Abstracts
polyelectrolyte microgels, we study the interactions between lysozyme (positively
charged) and negatively charged microgel particles of loosely cross-linked poly(acrylic
acid). When lysozyme is incorporated into the microgel, the composite system deswells
osmotically. We study how ionic strength, pH and lysozyme concentration affect the
interactions between protein and microgel. Binding isotherm studies show the effect on
protein loading. Confocal microscopy and micropipette-assisted light microscopy provide
information on the time-dependency in protein distribution and microgel deswelling,
respectively. At low ionic strength, protein incorporation is found to occur at lower protein
concentration. Lysozyme incorporation increases strongly with decreasing pH, a
pH-dependence which is less pronounced at lower ionic strength. Binding isotherms show
that lysozyme incorporation mostly is governed by protein charge, rather than by the
combined charge contrast. At some conditions a “lysozyme shell” forms in the microgel,
with much higher lysozyme concentration in the outer part than in the centre. Ionic
strength, pH and lysozyme concentration are found to determine whether shell formation
occur or not. High lysozyme concentration, low ionic strength and low pH all promote
shell formation. Shell formation strongly increases lysozyme uptake. It also affects the
binding kinetics of lysozyme to the microgels, resulting in a lag time, often in the order of
minutes, before any lysozyme can diffuse from the shell towards the microgel centre.
N1 – Invited Paper
USE OF PARTICLES AS EMULSION AND FOAM STABILIZERS
María I. Briceño, María T. Celis, Jean-Louis Salager, Laboratory FIRP,
School of Chemical Engineering, University of Los Andes, 5101 Mérida,
Venezuela, mabel@ula.ve
184
Although the stabilizing effect of colloidal-size nanoparticles on emulsions and foams has
been known since the early twentieth century, it has been the last 10 years that industry and
academia have acknowledged the vast potential of using particles as surfactants or
co-surfactants in the preparation and stabilization of dispersed systems. In fact, particles
are the main stabilizers of naturally occurring emulsions and foams, such as the ones
encountered in water-in-crude oil emulsions and froths in fermentation processes. In the
first part of the lecture, the mechanisms by which particles may stabilize a surface or an
interface are reviewed, as well as the effect of particle wettability, size and concentration
on stability. Some applications in the pharmaceutical and food industry are presented in the
second part, e.g., ice cream and multiple emulsions for controlled drug delivery.
Plenary 3
185
SUPERPARAMAGNETIC PARTICLES FOR DIAGNOSTIC AND
THERAPEUTICS, Heinrich Hofmann, Ecole Polytechnique Fédéral
Lausanne,EPFL, Institute of Materials, Powder Technology Laboratory,
Station 12, CH-1015 Lausanne, Switzerland; heinrich.hofmann@epfl.ch
Nanoparticles for biomedical applications such as target drug delivery, non-viral vectors
for gene delivery, contrast agent for in vivo imaging (MRI) or in biosensors have to fulfill
153
Oral Abstracts
very different requirements simultaneous. To achieve the physical requirements, such as
fast transport in a magnetic field gradient, local influence of the magnetic field strengths or
photoluminescence the particles has to be so small that properties like superparamagnetism
and quantum confinement determine the properties. From the biological point of view, the
size plays also an important role regarding up take mechanism by cells or to control the
colloidal behaviour in contact with blood. Recent results show that even more important
are the nature of the b In this presentation, methods for the synthesis of biocompatible
particles with properties which fulfill the physical as well as the biological needs will be
presented. Especially superparamagnetic particles for target drug delivery or for gene
therapy are difficult to synthesis, because several coatings of inorganic and/or organic
nature are necessary. Additionally derivatisations with biological molecules, which are
often larger then the core particle are needed. Th colloidal stability of the suspension
during fabrication and application is one of the major challenges during synthesis of the
particulate systems. In a second part a review medical application of such particles will be
given. Especially the relationship between particle properties, including surface properties,
and cells will be discussed. Additionally to the particle properties, external magnetic field
could have a interesting effect of transfection rate, drug targeting efficacy and the imaging
process.
A5 – Keynote Paper
EXPLOITING EMERGING TECHNIQUES IN IMPRINT LITHOGRAPHY
TO MAKE HIGHLY UNIFORM, SHAPE-SPECIFIC DRUGS, IMAGING
AGENTS, AND NANO-CARRIERS
Joseph M. DeSimone and Larken E. Euliss, University of North Carolina at
Chapel Hill, Department of Chemistry, CB #3290, Venable and Kenan
Laboratories, Chapel Hill, NC 27599; desimone@unc.edu
186
The delivery of therapeutic, detection and imaging agents for the diagnosis and treatment
of cancer patients has improved dramatically over the years with the development of
nano-carriers such as liposomes, micelles, dendrimers, biomolecules, polymer particles,
and colloidal precipitates. While many of these carriers have been used with great success
in vitro and in vivo, each suffers from serious drawbacks with regard to stability, flexibility,
polydispersity, or functionality. To date, there has been no general particle fabrication
method available that afforded rigorous control over particle size, shape, composition,
cargo and chemical structure. Recently, we have pioneered a contemporary breakthrough
in the materials useful for imprint lithography—an emerging technology adapted from the
microelectronics industry—that enables an extremely versatile and flexible method for the
direct fabrication and harvesting of monodisperse, shape-specific nano-biomaterials. By
utilizing the method we has designed referred to as Particle Replication In Non-wetting
Templates, or PRINT, we can fabricate monodisperse particles with simultaneous control
over structure (i.e. shape, size, composition) and function (i.e. cargo, surface structure). By
utilizing this method, we can impart control over the cross-link density of the polymeric
matrix. Unlike other particle fabrication techniques, PRINT is delicate and general enough
to be compatible with a variety of important next-generation cancer therapeutic, detection
and imaging agents, including various cargos (e.g. DNA, proteins, chemotherapy drugs,
154
Oral Abstracts
biosensor dyes, radio-markers, contrast agents), targeting ligands (e.g. antibodies, cell
targeting peptides) and functional matrix materials (e.g. bioabsorbable polymers or stimuli
responsive matrices). PRINT makes this possible by utilizing low-surface energy,
chemically resistant fluoropolymers as molding materials and patterned substrates to
produce functional, harvestable, monodisperse polymeric particles.
A5 – Invited Paper
MOLECULAR SPRING ASSEMBLIES OF NANOPARTICLES AND
NANOWIRES
Nicholas A. Kotov, Jim Lee, Departments of Chemical Engineering,
University of Michigan, Ann Arbor, MI; and A. Govorov, Department of
Physics, Ohio University, Athens, OH; kotov@umich.edu
187
The development of micro- and nano-fluidics devices demands in-situ measurements of
many parameters in the stream of liquids. Local gradients of solvent concentration,
temperature, pH and other parameters have tremendous importance for the development of
lab-on-a-chip applications and similar analytical tools. The same problem also appears in
biomedical fields that require evaluation of local concentrations and other parameters for
intricate geometries of 3D cell scaffolds, which affect the development of cells residing on
the scaffolds. Both tasks are difficult to accomplish using traditional sensor deployment
schemes, which often require substrate and wires. In this presentation, we address these
problems by designing a nanoscale sensing device from different types of nanoparticles
and nanowires connected by molecular springs made from flexible PEG oligomers. A
library of assemblies of nanoparticles and nanowires was created using PEG tethers. The
polymeric linkers afford continuous and dynamic change of conformations in such
structures leading to the variations of the distance between the nanoscale colloids
reversibly changes depending on conditions or analyte concentration and can be evaluated
by fluorescence measurements. Plasmon-exciton interactions result in tremendous
enhancement of luminescence and for some systems in characteristic wavelength shift
depending on the analyte concentration. Understanding plasmon-exciton interactions will
contribute to the photonics and nanoscale optics and create a knowledge base for other
technologies such as lasing in nanomaterials, energy conversion, and nanoscale electronic.
A5 – Contributed Paper
DEVELOPMENT OF NANOENGINEERED CALCIUM PHOSPHATE
-BASED PARTICULATES FOR GENE DELIVERY
Hyunbin Kim, Renato P. Camata, Rakesh Kapoor, Dept of Physics, Univ. of
Alabama at Birmingham, Birmingham, AL, USA; and Selvarangan
Ponnazhagan, Dept of Pathology, Univ. of Alabama at Birmingham,
Birmingham, AL, USA; camata@uab.edu
188
Particulate dispersions formed during co-precipitation of plasmid DNA and calcium
phosphate are widely used in gene transfection protocols. Despite its simplicity these
methods exhibit variable and often irreproducible efficiency. Basic investigations on the
155
Oral Abstracts
mechanisms of this versatile non-viral gene transfer methodology have been limited,
however, because of the heterogeneous nature of the calcium phosphate nanoparticles
commonly employed in these studies. Moreover, there are currently no efficient probes
capable of tracking the intracellular kinetics of gene transfer using calcium phosphate,
making detailed studies of gene delivery processes virtually impossible. Rare-earth doped
particles are well known for efficient infrared-to-visible upconversion. In this work, we
focus on the development of custom-designed calcium phosphate nanoparticles of
well-controlled size, structure and chemical composition that are doped with Er3+ or
Yb3+. The upconverted fluorescence of these doped calcium phosphate nanoparticles may
allow tracking of different intracellular processes involved in transfection. The
nanoparticles are produced using hybrid laser/aerosol method known as nanoparticle beam
pulsed laser deposition, in which a hydroxyapatite target containing ~0.01-0.1 wt.% of the
rare-earth species is ablated in inert gas. Nanoparticles formed are size selected, and
dispersed in balance solutions for subsequent mixing with plasmid DNA and exposure to
cells for gene transfer experiments. Nanoparticle sizes can be tuned in the 3-20 nm range
while nanoparticle concentrations may be varied between 105 and 109 cm-3 in solution. We
have targeted the control over crystal phase make-up of calcium phosphate nanoparticles,
which determines its dissolution behavior, and the rare-earth dopant concentration. If the
dissolution kinetics of these DNA-carrying nanoparticles can be matched to the temporal
sequence of specific cell cycles, there is a clear opportunity to exert control over the gene
transfer process. In-vitro measurements of gene transfer efficiencies as a function of
calcium phosphate nanoparticle size, composition, and chemical environment will be
discussed.
A5 – Contributed Paper
PRECISION ASSEMBLY OF MULTICOMPONENT
NANOPARTICULATE COLLOIDS
Joseph F. Bringley, Eastman Kodak Company, Research & Development
Laboratories, Rochester, NY 14250, joseph.bringley@kodak.com
189
We describe a general methodology whereby colloidal electrostatic forces can be utilized
to prepare a wide array of core-shell nanomaterials. The assembly process can be
described by simple geometrical considerations, and as such, the experimental method may
be adapted to design core-shell assemblies from a simple knowledge of the geometrical
relationship between the core and the shell. We show the precision-directed assembly of
particles upon particles, and polymers and molecules upon particles. We further show that
the method can be used to design nanoparticle colloids having complex and multiple
functionalities. The method is demonstrated in detail for polyelectrolytes assembled onto
silica nanoparticles. 1H NMR spectroscopy is used to evaluate the adsorption isotherm and
the saturation adsorption for polyethyleneimine assembled onto a 15 nm silica colloid. We
describe a method for crosslinking the polyelectrolyte shell and permanently fixing it to the
colloid surface, and demonstrate its effect on colloid stability. The colloid and surface
properties of the materials will be discussed in detail.
156
Oral Abstracts
A5 – Contributed Paper
THE SELF-ASSEMBLY BEHAVIOR OF THE CHOLESTERYL
DERIVATIVES OF ACYCLOVIR AND THE PREPARATION OF
SELF-ASSEMBLED NANOPARTICLES
Yiguang Jin, Rui Xin, Department of Pharmaceutical Chemistry, Beijing
Institute of Radiation Medicine, Beijing 100850, PR China;
jin_yiguang@yahoo.com.cn
190
We had prepared the self-assembled nanoparticles (SAN) from the long-chained glyceride
derivative of acyclovir in our previous works, and the SAN showed targeted delivery in
vivo and sustained drug release. We named the SAN-like aggregates prepared from
amphiphilic prodrugs as self-assembled drug delivery systems (SADDS). In this study, we
synthesized a new lipid prodrug of acyclovir – cholesteryl-succinyl-acyclovir (CSA), and
prepared the self-assembled nanoparticles. CSA was obtained through condensing succinyl
acyclovir with cholesterol. Also sodium salt of it (Na-CSA) was prepared. CSA was free
soluble in tetrahydrofuran (THF), a water-miscible solvent, and Na-CSA was soluble in
methanol. They are amphiphiles with cholesterol moieties and guanosine moieties.
Self-aggregates of the amphiphiles were tried to prepare using the injection method or the
film method, and CSA solutions in THF and Na-CSA solutions in methanol were used. A
homogeneous opalescent suspension containing about 2 mg/ml CSA and 50% THF was
obtained after CSA solution was injected into agitating water. After being kept at room
temperature for a few hours, the suspension would like to change to a white gel
(organogel). A lot of fibers were found in the gel with a negative-stained transmission
electron microscope (TEM). Contrastively, CSA could form vesicle-like nanoparticles (ca.
30-nm size) in the suspension without organic solvents using the film method. Na-CSA
always formed vesicle-like nanoparticles (ca. 50-nm size) using both the injection method
and the film method. The hydrophobic interaction between cholesterol moieties could
drive CSA and Na-CSA to self-assemble into bilayers and further formed vesicles.
However, in the THF-water media, the hydrogen bonds between guanosine moieties of
CSA would likely improve molecules aggregating head-to-head and extending into fibers.
No hydrogen bonds would form among Na-CSA due to the ionization of guanosine. The
self-assembled nanoparticles of CSA or Na-CSA might become a novel delivery system of
acyclovir.
A5 – Invited Paper
191
TARGETED NANOPARTICLES FOR BONE THERAPIES
Neal K. Vail; Southwest Research Institute, Microencapsulation and
Nanomaterials Department, 6220 Culebra Road, San Antonio, Texas 78238,
USA; nvail@swri.org
Maintenance of skeletal health is one of the more challenging current public health issues.
We are developing nanoparticles designed to target the mineralized phase of bone to
selectively deliver therapeutics to treat bone maladies and improve bone health. Our
current focus is the treatment of multiple myeloma with proteasome inhibitors, which are
157
Oral Abstracts
not selective to bone and their therapeutic-toxic window may be narrow. We previously
identified several bone-binding ligands and selected methylene bisphosphonate (MBP) as a
model targeting ligand. Amino-MBP was synthesized and its structure confirmed by 1H
NMR. This and other identified ligands were covalently linked via sulfhydryl conversion
of the amine to maleimide-terminated PEGylated phospholipids or polymers.
Functionalized PEG-b-PLA copolymers were synthesized and their composition
confirmed by NMR. Ligand attachment was confirmed by UV-Vis, NMR, and
MALDI-TOF/MS. Liposomes were prepared by controlled hydration and sized by
extrusion to typically 120nm. ± 20 nm. Lipid-ligand conjugates were inserted into the
preformed liposomes by post-insertion. Polymer nanoparticles were prepared by
nanoprecipitation and typically were 75nm to 150nm, depending on the nanoparticle
formulation. Particle size decreased with increasing PEG content. Similarly, zeta-potential
decreased with increasing PEG content, probably due to shielding of the PLGA surface by
the surface PEG groups. Ligand content of the various nanoparticle systems was quantified
by complexing the MBP with 99mTc and performing gamma counting. MBP ligand
contents varied between 0 and 5 mol % of the particle formulation. In vitro studies showed
that MBP ligands conjugated to the surfaces of nanocapsules convey preferential targeting
accumulating significantly on hydroxyapatite substrates, compared to
non-ligand-containing nanoparticles, which had no significant affinity for the HAp
substrate. We demonstrated the formulation and characterization of bone-targeting
nanoparticles. These nanoparticles preferentially adhere to bone-like surfaces in vitro. We
proceeding with in vivo studies to examine the biodistribution and uptake of these
nanoparticles.
A5 – Invited Paper
IRON NANOPARTICLES AS MAGNETIC CARRIERS
Shannon A. Morrison, Michael D. Shultz, Melissa A. Michaels, Sweta H.
Naik, Farrah N. Radwan, Everett E. Carpenter, Virginia Commonwealth
University, Chemistry Department, 1001 W. Main Street, Richmond, VA
23298, USA; ecarpenter2@vcu.edu, stuu@bluebottle.com
192
Magnetic carriers based on iron oxides are used almost exclusively due to biological and
chemical inertness. Because of the relatively weak magnetic flux density of iron oxides, the
nanoparticles need to be in the micron size range to withstand the flow conditions required
of a magnetic carrier. The inherent sizes of these particles have potential problems
however, such as prompting immunological responses and difficulty traversing the cell
membrane. We propose to use a multi-layer magnetic carrier based on iron metal
nanoparticles. This core-shell structure allows for smaller carriers, 10-20 nm in size, while
still retaining the necessary magnetic properties. Core-shell nanoparticles are synthesized
using the reverse micelle technique. Iron is first precipitated within the aqueous core using
sodium borohydride. The iron core then acts as a nucleation source for the subsequent iron
oxide shell formation. A description of the magnetic properties of these superparamagnetic
particles will be presented along with a comparison to other commercially available
magnetic nanoparticles.
158
Oral Abstracts
A5 – Contributed Paper
BROAD-BAND EFFICACY DETERMINATION FOR DISCRETE SILVER
NANOPARTICLES
Stan Farnsworth, Nanotechnologies, Inc.1908 Kramer Ln, Building B,
Austin, TX 78727, stan.farnsworth@nanoscale.com
193
Silver has long been known to demonstrate anti-microbial efficacy with an ionic
interaction mechanism. Now, discrete non-aggregated silver powders with average
particle size 25 nm produced by Nanotechnologies, Inc have been established to have
efficacy with bacteria, virus, and fungus, including vegetative as well as dormant spore
forms. Bacterial forms tested include gram-positive and gram-negative, while viral forms
include both enveloped and non-enveloped, as well as DNA and RNA cores. Notably,
work has demonstrated that the particles have a direct interaction with the pathogens,
beyond the traditional ionic mechanisms. Electron imaging shows that bacteria walls are
lysed, and virus capsids have silver attached corresponding with specific protein sites.
Work is now shifting to determining the efficacy of the silver nanoparticles when used as
simple surface coatings, incorporated into polymers, and suspended in creams and
ointments. Results from these tests could indicate likely best-commercial application
candidates, including medical textiles, hospital and food-preparation surfaces, wound
dressings, and veterinary products.
A5 – Invited Paper
NANOCLUSTERS AS A UNIQUE DRUG DELIVERY PLATFORM
Lianjun Shi1 and Cory Berkland1,2; 1Department of Chemical and Petroleum
Engineering, University of Kansas; 2Department of Pharmaceutical Chemistry,
University of Kansas; berkland@ku.edu
194
Clusters of nanoparticles, also referred to as agglomerates, colloidal clusters or colloidal
crystals, are a class of assemblies at the micrometer or sub-micrometer scale consisting of a
large number of closed-packed nanoparticles. Materials such as these offer some
intriguing properties not observed in the bulk forms of corresponding materials. For
instance, three dimensional assemblies of uniform nanoparticles can be designed to exhibit
a full photonic band gap not seen in dispersions of the same. New techniques to synthesize
organic or inorganic nanoparticles demonstrating control of size, size distribution, and
surface chemistry, continue to fuel emerging nanocluster applications. Typically,
nanoclusters are not able to disperse into individual nanoparticles, even when applying
intense sonication. The proximity of nanoparticles leads to irreversible agglomerates held
together by strong van der Waals interactions. Here we report nanoclusters with
pharmaceutically relevant properties such as pH-sensitive dispersion and biodegradability,
using solvent-extraction and self-assembly fabrication techniques.
159
Oral Abstracts
G2 – Keynote Paper
THE CELLULAR AND MOLECULAR TOXICITY OF LOW SOLUBLITY
NANOPARTICLES
Vicki Stone, Centre for Health and Environment, School of Life Sciences,
Napier University, Edinburgh EH10 5DT, UK; v.stone@napier.co.uk
195
The number and diversity of newly engineered nanoparticles is steadily increasing due to
their applications in medicine but also in food, clothing, cosmetics and IT applications.
Due to the wide variety of applications for which these are developed, including, the
potential for human exposure is inevitable and so it is important to consider the hazard of
these materials. Although new nanoparticles for medical applications are usually
thoroughly tested prior to clinical use, the mechanism of toxicity is often poorly
understood. Improved understanding of such mechanisms could help in the improved
design of new nanoparticles. The toxicology of bulk manufactured nanoparticles such as
carbon black, TiO2 and polystyrene beads hax been investigated for several years, often in
relation to investigating the mechanisms driving the adverse health effects of ambient air
pollution. The results from these studies are useful in providing a platform from which an
effective strategy for nanoparticle toxicity testing can be established. We have previously
reported that carbon (14 nm diameter) or polystyrene (54 nm diameter) nanoparticles
generate more inflammation in the rat lung than larger particles, and this inflammation is
correlated well with the surface area of the particle dose. The smaller particles have been
demonstrated in a number of assays to generate more reactive oxygen species (ROS) than
larger particles leading to oxidative stress in the lung epithelial cell lines and in
macrophages. In addition non-lethal doses of these particles induced a significant increase
in cytosolic calcium leading to the production of the pro-inflammatory cytokine tumour
necrosis factor alpha (TNFα). In conclusion, the relatively small size of nanoparticles
enhances their potency in a number of in vivo and in vitro systems resulting in the
production of oxidants and the generation of pro-inflammatory mediators. Such test
systems would be useful in investigating interactions between medical nanoparticles and
the body. Funding: The Colt Foundation and BP.
G2 – Invited Paper
FORMULATION PROCESSES AND CHARACTERIZATION OF DNA
AND siRNA NANOPARTICLES
R. Knowle, A. Werner, M. Fisher, and Rob DeLong, Louisburg College, 501
N. Main Street, Louisburg, North Carolina 27549, USA;
rkdelong@louisburg.edu
196
There are a wide variety of potential applications for nucleic acid-peptide nanoparticles in
research and development ranging from molecular medicine to diagnostics. My research
interests are in formulation processes and characterization chemistry for nanoparticles
formed of DNA and RNA. In previously published work we have studied nanoparticles
formed when plasmid DNAs or antisense oligomers were complexed with cationic
polymers, protamine, polyarginine or oligo-ARG, and the relationship between their
160
Oral Abstracts
physico-chemical characteristics and chemical, biochemical or biological activity. More
recently we have been studying sedimentation and partitioning methods for preparing these
types of nanoparticles and have extended them to the preparation of siRNA and DNA
vaccines. These types of particles are limited by relatively inefficient and heterogenous
loading or coating capacities and by their tendency to aggregate and to precipitate in
physiological fluid and serum containing media. Further their bioprocessing,
down-stream, sterilization and storeage steps can often lead to the chemical degradation of
the bio-molecules even before any enzymatic based mechanisms in serum or their delivery
to cells and tissues. We are using a combinatorial and design of experiment approach
towards developing more effective means of producing nanoparticles with better loading
and stability properties. Taking into account and using to our advantage in some cases,
some of these properties to better prepare nanoparticles on this basis, using a high
throughput luciferase splice-site correction model to rapidly screen nanoparticles produced
under a variety of design of experiments screening for their biological activity.
G2 – Contributed Paper
PHYSICOCHEMICAL ANALYSIS AND EFFECTS ON YEAST CELLS OF A
PARTICULATE TRADITIONAL INDIAN MEDICINE, JASADA BHASMA.
Tridib K. Bhowmick, A. K. Suresh, S.G. Kane, Jayesh R. Bellare, Department of
Chemical Engineering, Indian Institute of Technology Bombay, Powai, Maharashtra,
Mumbai-400076, India; and Ajit. C. Joshi, 22, Shukrawar Peth. Pune, Maharashtra,
India; tbhowmick@iitb.ac.in
197
Herbo-mineral preparations called Bhasma are unique to Ayurveda and Siddha system of Indian
traditional medicine. These preparations are particulate powders and have long been used and
claimed to be an effective and potent medicine. However, there are only a few analytical
scientific studies carried out on these products, and even these suffer from incomplete analysis.
Use of a wide variety of materials (e.g. minerals, metals, herbal juices) during manufacture also
makes these kinds of medicines extremely difficult to analyze. In this study, different analytical
techniques have been employed for complete elemental analysis as well as the physical
characteristics of Jasada Bhasma which is made from zinc metal. When analyzed with the help of
XRD, it shows the presence of hexagonal ZnO as a major phase in the sample. For ICP analysis
the sample completely dissolved by a two step process. In the first step sample was dissolved in
(1:1) mixture of conc. HNO3 and HClO4. The bulk of the sample dissolves in such a solution. The
residue which is still left behind is dissolved in acid after digesting with LiBO2. The analysis
result shows that the sample contains eleven elements (Na, Mg, Al, Si, S, Ca, Mn, Fe, Cu, Zn and
Sn) among which Zn is present in maximum amount (78.57 wt %). EDAX has also been done to
confirm the elemental composition. It detects the same eleven elements plus oxygen (11.70 wt%)
and this result is in good agreement with the ICP result. An interesting finding is that oxygen
(32.63 atom %) present in the material is not stoichiometrically sufficient to satisfy all the Zn
(54.07 atom %) as a ZnO, nor with the other metals present. Combining the XRD, ICP and EDAX
result it can be said approximately equal amount of amorphous Zn present in the sample. The size
and size distribution of the particles have been determined by employing DLS and TEM. Particle
size distribution has been studied after suspending the materials in aqueous dispersing phase at
pH 3.0 and filtering through 0.22 micron membrane filter. TEM photographs of the filtrate show
161
Oral Abstracts
considerable amount of particles present in the nanoparticle (10-15 nm) range. The biological
activity of Jasada Bhasma medicine has been studied by growing Saccharomyces cerevisiae cells
in shaker flask in presence of 300ppm Bhasma sample. The result revealed that cell cycle of
Saccharomyces cell changed dramatically when they are treated with small size (below 500nm)
particles.
G2 – Invited Paper
PHYSICAL PROPERTIES AND CYTOTOXICITY OF INORGANIC
NANOPARTICLES FOR BIOMEDICAL APPLICATIONS
Gan-Moog Chow, Department of Materials Science and Engineering,
National University of Singapore, Kent Ridge, Singapore 119260.
msecgm@nus.edu.sg
198
Inorganic nanoparticles find potential applications in targeted delivery of drugs and
biomolecules, separation, sensing and imaging. The properties of nanoparticles depend
not only on the size but also the structure, microstructure and surface coating. In this talk,
examples of some of our work on inorganic nanoparticles for biomedical applications are
presented. Near-infrared-sensitive Au-Au2S, magnetic γ-Fe2O3 and NiFe2O4, and
IR-to-visible upconversion fluorescent Yb-Er, Yb-Ho and Yb-Tm co-doped LaF3
nanoparticles were chemically synthesized. The physical and chemical properties were
optimized for the application in question. For drug delivery, surface modification of
particles using suitable surfactants was tailored for adsorption and release of anti-cancer
drugs (cis-platin or carboplatin). For bio-probes and displays, visible emission of colloidal
up-conversion nanocrystals under IR excitation was studied and compared with the
NaYF4:Yb,Er nanocrystals. The cytotoxicity of nanoparticles depends not only on the
particle size but also the surface coating, both of which are controlled by the synthesis and
processing conditions. For example, the dependence of cytotoxicity on particle size and on
the presence of oleic acid as surfactant on nickel ferrite particles were investigated in vitro
using the Neuro-2A cell line as a model. For nickel ferrite particles without oleic acid
prepared by ball milling, cytotoxicity was independent of particle size within the given
mass concentrations and surface areas accessible to the cells. For nickel ferrite particles
coated with oleic acid prepared by the polyol method, the cytotoxicity significantly
increased when 1 layer or 2 layers of oleic acid were deposited. Large particles showed a
higher cytotoxicity than smaller particles. The effects of surface energy and effective
interaction areas of adsorbed functional groups on cytotoxicity were suggested.
G2 – Invited Paper
GREEN NANOTECHNOLOGY THROUGH COLLABORATIVE
RESEARCH ON MECHANISMS OF NANOMATERIAL TOXICITY
Agnes B. Kane and Robert Hurt, Department of Pathology and Laboratory
Medicine and Division of Engineering, Brown University, Providence, RI
02912; Agnes_Kane@brown.edu, Elizabeth_Fox@brown.edu
199
It is now recognized that the recent world-wide investment in new nanomaterials should be
162
Oral Abstracts
accompanied by parallel efforts to explore and understand their potential impacts on
human health and the environment. By virtue of their small size, nanomaterials may
penetrate biological membranes, enter cells, carry high concentrations of adsorbed species,
or show elevated surface reactivity relative to their macroscopic counterparts. This talk
introduces the emerging field of nanotoxicology and presents results from our
collaborative research on carbon nanomaterials. It will be shown that iron nanoparticles
that are residues of the growth catalyst can be redox active, produce DNA damage, and are
toxic to macrophages. A unique feature of this effort is a close collaboration between
toxicologists and materials scientists with the joint goal of identifying the specific material
features (size, shape, surface chemistry, purity) that contribute to toxicity. The long-term
promise of this approach is to learn how to modify synthesis or purification procedures to
fabricate “green” nanomaterials – those co-optimized for performance and minimal health
impact. This research was supported by the grants from US-EPA, NSF, NIEHS, and the
Superfund Basic Research Program.
G2 – Invited Paper
NANOPARTICLE INTERACTIONS WITH THE CYTOSKELETON
James McGrath and Morton Ehrenberg, Department of Biomedical
Engineering, University of Rochester, Rochester NY 14642, USA;
jmcgrath@bme.rochester.edu
200
The use of nanometer particles as intracellular mechanical probes requires the design of
particles with controlled and specific interactions with cytoskeletal filaments. Also, the
demonstrated toxicity of some nanoparticles particles is of increasing concern as
nanoengineered materials become more commonplace in industry and the environment.
With these issues in mind, we characterized the natural capacity of various particles to bind
to the proteins contained in fibroblast cytoplasm and bovine brain extracts. We found that
all particles tested (polystyrene, TiO2, and SiO2 with various levels of surface
carboxylation) bound primarily to cytoskeletal proteins in both types of extracts, although
the profile of bound proteins do vary with particle surface chemistry and extract type. In
the fibroblast extracts, we found that carboxylated polystyrene beads bind most
prominantly to actin and the intermediate filament protein vimentin, and through surface
modification we could eliminate the binding of actin. These biochemical studies were
supported with microrheological measurements in living fibroblast cytoplasm. Here we
tracked microinjected particles with high temporal and spatial resolution inside of cells and
found that the untreated particles made random movements of diminshed amplitude
compared to the particles treated to block actin binding. We also found that the random
movements of the two nanoparticles chemistries were indistinguishable when the particles
were endocytosed rather than microinjected, and that the amplitude of the motion of
endocytosed particles was significantly higher microinjected particles. There is
considerable evidence in the literature that small nanoparticles can circumvent the
membrane trafficking pathways of cells to become free in cytoplasm. Our data suggests
that the such particles will strongly interact with the elements of the cytoskeleton.
163
Oral Abstracts
O1 – Keynote Paper
NANOPARTICULATE VACCINE DESIGN: THE VESIVAX SYSTEM
Gary Fujii, Molecular Express, Inc., 13310 South Figueroa Street, Los
Angeles, CA 90061; gfujii@molecularexpress.com
201
The VesiVax® system is based upon the concept that highly potent vaccines can be
designed by engineering proteins that are capable of stably inserting themselves into
nanoparticulate liposomes. Such a nanoscale liposomal particle could then serve as an
immunogen for vaccine development. This approach requires a fundamental
understanding of the interactions of proteins and/or peptides with lipid bilayers and an
in-depth knowledge of the processes used in the commercial preparation of liposomes.
Structural and functional studies on the interactions of proteins and peptides with lipid
bilayers previously identified structural amphiphilicity and hydrophobicity as important
parameters that control the nature of the interaction between proteins and membranes. The
VesiVax® vaccine technology platform takes advantage of these parameters and features a
flexible and easily modified gene cassette designed to rapidly engineer and produce, using
standard recombinant manufacturing processes, antigen fusion proteins that are compatible
with liposomal bilayer membranes. The recombinant antigen proteins are fused to an
aqueous soluble hydrophobic domain that makes purification simple and allows stable
insertion of the immunogen within the lipid membrane. This technology eliminates the
issues associated with hydrophobic protein domains that have previously made large-scale
vaccine development difficult.
Vaccines based on the VesiVax®system have been developed against the influenza virus
and herpes simplex type 2 virus, the causative agent of genital herpes. Both vaccines have
been tested in animal models and have demonstrated significant protective efficacy from
challenge with lethal doses of virus. Assays of the immunological parameters suggest that
both T and B cell responses can be elicited by VesiVax® vaccines. The safety profile of the
VesiVax® vaccines is expected to be much better than that of vaccines prepared by
conventional techniques.
O1 – Invited Paper
CLINICAL DEVELOPMENT OF A THERAPEUTIC MICROPARTICLE
FORMULATION
Thomas M. Luby and Mary Lynne Hedley, MGI PHARMA Biologics. 44
Hartwell Ave. Lexington, Ma. 02421; thomas.luby@mgipharma.com
202
Injection of microparticle encapsulated DNA has been shown to elicit immune responses
to the plasmid-encoded antigens, and the use of this technology in a therapeutic cancer
vaccine is described. The tumor-associated antigen Cytochrome P450 1B1 (CYP1B1) is
overexpressed in many tumor types, but has a relatively restricted normal tissue expression
profile, making tumors that express it excellent targets for immunotherapy. Despite the
fact that it is a self protein, T cells specific for CYP1B1 epitopes exist in the human
repertoire, and these are cytotoxic for tumor cells expressing the antigen. Microparticle
formulations containing plasmid DNA are phagocytosed by antigen presenting cells
resulting in the expression of the antigen-encoding DNA in cell types well suited for
164
Oral Abstracts
inducing an immune response. Preclinical studies in mice have demonstrated that a
formulation made of PLGA microparticles encapsulating a CYP1B1 encoding plasmid
DNA are able to induce immune response to CYP1B1. Additionally, it appears that the
microparticle formulation has natural adjuvant activity and is amenable to alterations that
result in enhanced immunity. This formulation has been tested in a phase I clinical trial of
17 patients with various cancers types, and was shown to be safe and well tolerated.
Interestingly, clinical efficacy appeared to correlate with immune responses induced by the
drug, leading to strategies to further potentiate the immune response in subsequent trials.
O1 – Contributed Paper
BIOMIMETIC PARTICLES FOR VACCINE DESIGN
Nilton Lincopan, Noeli M. Espíndola, Adelaide J. Vaz, Ana M.
Carmona-Ribeiro, Instituto de Química, Dept. Bioquímica, Universidade de
São Paulo, P.O.Box 26077, 05513-970 São Paulo, SP, Brazil; Faculdade de
Ciências Farmacêuticas, Laboratório de Imunologia, Universidade de São
Paulo, São Paulo, SP, Brazil; amcr@usp.br
203
Electrostatically driven bilayer coverage from bilayer fragments onto oppositely charged
latex produces a highly homodisperse particulate for antigen presentation. Polystyrene
sulfate (PSS) particles were covered with single cationic dioctadecyldimethylammonium
bromide (DDA) bilayers and used for antigen adsorption and presentation. The antigen was
a mixture of recombinant 18/14 Taenia crassiceps proteins (18/14-Tcra). Firstly, the
DDA/PSS assembly was characterized at 5 x 109 PSS particles/mL over a range of DDA
concentrations (0.01-1 mM) by means of dynamic light scattering for particle sizing and
zeta-potential analysis. 0.01 mM DDA is enough to produce perfectly homodisperse and
cationic bilayer-covered particles. Secondly, under these experimental conditions,
18/14-Tcra adsorption isotherms onto biomimetic particles or onto aluminum hydroxide
(Freund`s adjuvant) yield limiting adsorption of 0.36 and 1.32 mg protein adsorbed per mg
biomimetic particles or Al(OH)3, respectively. Finally, the foot-pad swelling test for
delayed type hypersensitivity, a marker for cellular immunoresponse, was performed in
mice to prove the higher efficiency of antigen presenting biomimetic particles in
comparison to Freund´s adjuvant under equivalent experimental conditions and antigen
concentration. Thereby, this work represents a proof-of-concept that cationic
bilayer-covered particles represent a novel, highly organized and general immunoadjuvant
for antigen presentation and subunit vaccine design. Financial support: FAPESP and CNPq
O1 – Invited Paper
DESIGN OF SYNTHETIC COLLOIDAL ANTIGEN CARRIERS FOR
VACCINE PURPOSES
Thierry Delair, Unité-Mixte CNRS-bioMérieux, ENS-Lyon, 46 allée d’Italie
69007 LYON; Thierry.Delair@ens-lyon.fr
204
Vaccine have long been based on the use of attenuated or denaturated pathogens injected to
patients. To improve the safety of new vaccines, instead of the whole pahtogen, sub-units
165
Oral Abstracts
can be used, i.e. one or several proteins cons tituting the pathogen (or the genes coding for
them). But to have an efficient immune response, antigen carriers have to be used with the
antigen either within the matrix of the polymer or adsorbed onto the surface of the
particles. The physico-chemical properties of the particles have to be tuned to the
applications. In this presentation we will adress various methods to obtain colloidal carriers
for either the delivery of DNA or proteins and we will describe some results obtained in
various animal samples. Particles for the delivery of DNA need to be positively charged in
order to interact via electrostatic interactions. Various cationicpolymers have been
immobilized onto the surface of the colloid and we will show that not only the chemical
nature of the polymer but the elaboration process as well impact the adsorption process of
the DNA. For protein delivery, we will show that surfactant free particle can be efficient
antigen carriers that can ellicit both cellular and humoral responses in various animal
models such as mice, rabbit and non-human primate.
O1 – Invited Paper
NOVEL INJECTABLE BIOMATERIALS FOR PROTEIN AND VACCINE
DELIVERY
Balaji Narasimhan, Department of Chemical and Biological Engineering,
Iowa State University, 2035 Sweeney Hall, Ames, IA 50011-2230, USA;
nbalaji@iastate.edu
205
Polyanhydrides are a class of hydrophobic biomaterials that degrade by hydrolytic
cleavage of the anhydride bond and their hydrophobicity confers a “surface erosion”
mechanism upon them. Our overall objective is to engineer polyanhydrides with tailored
chemistry and nanostructure to regulate drug/protein distribution and to design delivery
systems with physiologically meaningful release profiles. Two examples of controlled
delivery systems based on these materials will be discussed. First, proteins can be
stabilized within and released from polyanhydride microspheres. The effect of polymer
chemistry, and microsphere fabrication method on the structure and activity of several
proteins was investigated. It was found that the mechanism of denaturation of the protein
and its interactions with the polymer carrier play a significant role in the design of the
delivery system. A systematic approach was developed for selecting compatible
polymer/protein systems prior to encapsulation. Second, single dose vaccine carriers
based on polyanhydrides were designed with the unique capability to modulate immune
response mechanisms. Our studies have shown that by altering the chemistry of the
polyanhydride, a TH2 response can be selectively diminished without reducing the overall
antibody titer. This leads to a balanced TH1/TH2 response, which has important
implications for developing vaccines to intracellular pathogens. The fundamental
treatment of the mechanistic aspects of release and immune response will ultimately
facilitate rational means of designing single-dose vaccines.
D5 – Keynote Paper
COLLOIDAL ASSEMBLY EXTENDED INTO THE BIOMATERIALS
DOMAIN: COMPOSITE COATINGS AND MEMBRANES FROM LIVE
206
166
Oral Abstracts
CELLS
Orlin D. Velev, Shalini Gupta, Lindsey B. Jerrim, Rossitza G. Alargova and
Peter K. Kilpatrick; Department of Chemical and Biomolecular Engineering,
North Carolina State University, Raleigh, NC 27695-7905, USA;
odvelev@unity.ncsu.edu
The co-assembly of live cells and synthetic nanoparticles could be a route to making new
biomaterials, in which the functionality of the cells is complemented by the functionality of
the particles. We will demonstrate a few classes of such biocomposite materials made by
using techniques for controlled colloidal assembly into 2D and 3D structures that we have
developed earlier. We will first demonstrate how on-chip dielectrophoresis can be used to
co-assemble arrays of latex spheres and yeast cells or NIH/3T3 mouse fibroblasts.
Depending on the frequency of the field and relative polarizability of the cells and
particles, one and two dimensional assemblies can be obtained. These arrays can be bound
into permanent biocomposites by using lectin-conjugated spheres as biocolloidal binders.
Particles with magnetic cores added an additional functionality to the live cell 2-D matrix
and we were able to manipulate these materials with external magnetic fields. Such
cell-nanoparticle chains and membranes can form the basis of sensors, microscopic
bioreactors and artificial tissue. We also present a method for assembling and
immobilizing large-scale coatings from yeast cells. The coating method is based on
convective assembly and deposition in a moving meniscus to make close packed
two-dimensional arrays. A robust technique for rapid deposition of monolayer cell
coatings was designed on the basis of this method. One immediate application of these cell
coatings is in biosensors and test beds for toxicity and drug action.
D5 – Invited Paper
GENETIC CONTROL OF NANOPARTICLE ASSEMBLY AND ITS
APPLICATION IN COLORIMETRIC SENSING
Yi Lu,* Juewen Liu and Daryl P. Wernette, Department of Chemistry,
University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA;
yi-lu@uiuc.edu
207
Genetic control of synthesis and properties of nanoparticles in response to chemical stimuli
under ambient conditions has been one of the hallmarks in biology. Employing such a
process in nanopartcle research can result in novel nanomaterials that rival or even exceed
the structural and functional properties of naturally occurring materials. Toward this goal,
we have taken advantage of recent advance in biology where catalytic DNA molecules
(DNAzymes) or aptamers can be selected from a large (up to 1015 different) DNA library
with specific binding selectivity toward an analyte of choice. By using DNAzyme, aptamer
or aptazymes for directed assembly gold nanoparticles, genetic control of such assembly in
response to chemical stimuli such as metal ions or organic molecules have been
demonstrated. Because of the highly intense color change from the blue assembled gold
nanoparticles to the disassembled red particles, this work has resulted in simple, sensitive
and selective colorimetric sensors for a number of molecules. A careful investigation of
the DNAzyme biologyhas resulted in a new derivative of DNAzyme that allows a tunable
167
Oral Abstracts
assembly of nanoparticle and thus tunable dynamic range of detection. In addition, a
detailed understanding of DNAzyme and nanoparticle interactions resulted in
imporvemnet of the sensor performace, allowing room tempeature and fast operation for
on-site, real-time sensing, much the same as pH indicators. In addition to controlled
assembly of materials, biology also controls the disassembly of materials in responsive to
chemical stimuli so that useful materials can be released or harmful processes can be
prevented. We have recently succeeded in employing such a process in disassemble gold
nanoparticle aggregates in responsive to metal ions such as Pb2+. This endeavor has
resulted in even further improvement of the colorimetric sensor by transforming a
“light-down” sensor into a “light-up” sensor. Recent progress in this work will be
presented.
D5 – Contributed Paper
DEVELOPMENT OF A MULTIPLEX PEPTIDE NANOTUBE-BASED
PATHOGEN ASSAY
Robert I. MacCuspie, Hiroshi Matsui, Department of Chemistry, Hunter
College and The Graduate Center of the City University of New York, 695
Park Ave, New York, NY 10021, nano_rob@yahoo.com; Ipsita A. Banerjee,
Department of Chemistry, Fordham University, Bronx, NY; Andrea Bertke,
Sanjay Gummalla, Howard Mostowski, Phil Krause, U.S. Food & Drug
Administration, Center for Biologics Evaluation and Research, 29 Lincoln
Drive, Bethesda, MD 20892.
208
Rapid detection of pathogens is of key importance in both the fight against bioterrorism
and in the screening of regulated products such as vaccines and blood supplies. Here, a
novel multiplexed peptide-nanotube based assay is presented that detects in-tact, whole
viruses in solution both rapidly and efficiently. Using multifunctional peptide nanotubes
coated at the ends with detecting antibody and along the sidewalls with fluorescent dye
signaling molecules, the nanotubes bind to viruses to form three-dimensional networks
whose size and fluorescence intensity increase proportionally to the virus concentration.
Antibodies bind the virus creating an aggregate with a central core containing nanotube
fingers radiating outward similar in shape to a sea urchin. As the concentration of virus
increases, additional viruses tether these sea-urchin structures together into 3-D fluorescent
scaffold-like networks. In this system, fluorescent intensity is directly proportional to the
size of each network. Flow cytometry allows collection of scattering data concurrently
with fluorescent data, confirming the correlation between the 3-D network size and
fluorescent intensity. When the ratio of nanotubes to virus was very high formation of
several smaller networks was favored as opposed to fewer larger networks. This method
allows determination of an unknown virus concentration level down to trace levels as low
as 100 virus particles per mL in a 0.5mL sample. Standard curves of fluorescent intensity
vs. concentration of virus were created for several different viruses. By assigning different
antibodies to unique fluorophores, detection of several fluorescence intensities
simultaneously is possible. Proof of principle experiments were performed to quantify a
mixture of two viruses. The multiplex ability of the system is only limited by the ability to
resolve each unique fluorophore and the number of photodetectors on the flow cytometer.
168
Oral Abstracts
D5 – Contributed Paper
SURFACE MODIFIED LANTHANIDE DOPED NANOPARTICLES AS
NEW ROBUST BIOLABELS
Frank van Veggel, University of Victoria, PO Box 3065, Victoria, British
Columbia, V8W 3V6 Canada. fvv@uvic.ca
209
Trivalent lanthanide (Ln3+) ions have unique optical transitions in the sense that they have
quite sharp, almost line-like, non-overlapping absorption and emission bands from the
visible to the near-infrared (which could be adavantageous in multiplexing). In addition,
they can have several long-lived excited states, from micro- to millisecond, allowing easy
removal of autofluorescence from, for instance, biological moieties through gated
spectroscopy. Moreover, they have efficient upconverting processes that convert
low-energy photon into high-energy photons. These characterstics make these ions
potentially very useful as biolables. In particular, absorption and emission in the
near-infrared allow for deeper tissue penetration and their photocycles are extremely
robust. We have developed routes to stabilize Ln3+ doped LaF3 nanaoparticles with ligands
such as citrate and 2-aminoethylphosphate to make them water soluble, with retention of
the emissive properties of the dopant Ln3+ ions. The primary amine of the 2-aminoethylphosphate ligands could be reacted with activated esters to impart biological function, i.e.
introduction of specific ligands such as biotin. Binding studies with immobilized avidin on
beads showed that specific binding had been achieved. The second route we developed is
based on the coating of these nanoparticles with a thin layer of SiO2 in order to have a
material that can easily be functionalized and is benign to animals and human. Primary
amino or thiol groups can be introduced by standard silane chemistry and reacted further to
introduce a biological function (i.e. biotin). Binding studies with the avidin that was
labeled with fluoresceine as marker showed that specific binding had been obtained. This
approach led to very effcient emission from the visible, Eu3+ and Tb3+, to the near-infrared
(Nd3+ and Er3+). Moreover, effcient upconversion was achieved though the Yb3+ sensitized
emission of Er3+ and Tm3+. The latter is particularly attractive because the excitation at
980 and the emitted upconverted light at 800 are both in the water window.
D5 – Contributed Paper
NANOPARTICLE QUANTUM DOTS FOR TARGETED
NEUROMODULATION
Tania Q. Vu, Department of Biomedical Engineering, Oregon Health &
Sciences University, 20000 N.W. Walker Road, Beaverton, OR 97006-8921;
tvu@bme.ogi.edu
210
Increased interest in nanocrystal quantum dot (QD) technology as fluorescent probes
possessing unprecedented brightness, photostability, and multi-color capability has made
apparent their promising potential for live tracking of single cell and in vivo processes.
Presently, QD biorecognition is largely achieved through attachment of antibodies to the
QD surface, resulting in a bio–inorganic complex combining biomolecular-specificity with
fluorescence. A less explored approach is to use small ligands or synthetic analogs that
169
Oral Abstracts
when conjugated to the QD, would bind not only to receptor proteins, but also serve to
activate signaling cascades that regulate cellular phenotype and behavior. Here we discuss
the development of QDs complexed with nerve growth factor, a peptide hormone
belonging to the family of neurotrophic factors that has generated therapeutic interest due
to the ability of these factors to promote the survival of central and peripheral neurons after
neuronal damage and during development. Surface modification and composition of
complexed QD nanostructures were confirmed and bioactivity of ligands and ligand-QD
complexes were tested using functional imaging based assays. Despite known structural
and chemical stringency of ligand-receptor activation, evidence supports activation and
modulation of cell function and behavior. Three aspects of this work will be discussed: 1)
design and assembly of drug-bound QDs, 2) visualization and chemical analysis of
biomolecule-coupled quantum dot complexes, and 3) anatomical and physiological
targeting in neural tissue. Development of this QD-based capability bears significance for
development of tools for studying inter-molecular interactions, assessing effectiveness of
drug compounds, and visualization of cellular function for a variety of biological studies.
D5 – Invited Paper
TARGETED AND FUNCTIONAL NANOPARTICLES FOR BIOMEDICAL
DIAGNOSTICS
Yvon Durant, Romuald Couronne University of New Hampshire, Materials
Science Program, G101 Parsons Hall, durham NH 03824, USA; and Ebo de
Muinck, Angiogenesis Research Center, Dartmouth Medical School, Borwell
Research Building 734E, HB 7700, 1 Medical Center Drive, Lebanon, NH
03756, USA; yvon.durant@unh.edu
211
Medical diagnostic can be facilitated by the use of magnetic nanoparticles tagged with
specific homing peptides. The synthesis of such particles is done in 3 steps. The first one is
the synthesis of the magnetites (the core of the particles), the second step concerns their
encapsulation into a protective polymer shell, and the third step is the functionalization
with a homing peptide and optionally a fluorescent tag. The synthesis is done from Iron II
and Iron III salts in basic conditions in the presence of oleic acid. This process create
primary magnetite particle in the size range or 8-25nm. Upon liquid extraction of the
aqueous dispersion with styrene we obtain an organic dispersion of magnetite at solid
content ranging up to 20%. To this organic solution is added hexadecane and acrylic acid,
which is in term sonicated with an aqueous solution of sodium dodecyl sulfate. Upon
polymerization with potassium persulfate, a unimodal miniemulsion is obtained with an
average size of 130nm. This magnetic latex is then diluted to 5% solid content and
ultrafiltrated on 100KD cellulose filters to eliminate residual monomers with Potassium
buffer system (PBS). The latex is then functionalized with an adhesion promoter amino
functional peptide such as cNRG and tagged with a fluorescent label, such Alexa Fluor 647
Cadaverine in the presence of a carbodiimide coupling agent such as EDCI. The coupling
yield is 50%. The particles are again ultrafiltrated with PBS to eliminated uncoupled
molecules. The resulting particles have a ferromagnetic behavior and have a saturating
magnetic moment of 50 emu/g at 0.1 T. These diagnostic nanoparticles can be used both in
confocal fluorescence microscopes, fluoro-endoscopes and Magnetic Resonance Imaging
units.
170
Oral Abstracts
D5 – Invited Paper
DETECTION OF DRUGS OF ABUSE USING A MAGNETIC BIOSENSOR
F. de Theije, T. van der Wijk, W. Hardeman, H. Brans, A. Immink; Philips
Research and Philips Applied Technologies, High Tech Campus 4 (WAG02),
5656AE, Eindhoven, The Netherlands, and S. Marlin, A. Jehanli, D. Baldwin,
G. Jowett, Cozart plc, 92 Milton Park, Abingdon, Oxfordshire, UK OX14 4RY;
femke.de.theije@philips.com
212
We are developing assays for fast detection of drugs of abuse in saliva, based on giant
magneto-resistance (GMR) biosensors packaged in a compact disposable microfluidics
cartridge. The possibility of magnetic actuation, which rapidly concentrates the
magnetically labeled bio-molecules at the sensor surface, is a unique feature of the
magneto-electronic device that allows a fast assay by speeding up reaction time and
making time-consuming fluid wash steps obsolete. The high signal to background ratio due
to the fact that body fluids are non-magnetic makes the GMR the device of choice for drugs
of abuse testing. Additionally, electronic callibration techniques make the system very
robust in diverse environments among which the road-side environment. Drugs of abuse
generally are small molecules that only possess a single epitope for antibody binding, thus
requiring a competitive assay format. Our assays are based on the capture of biologically
functionalized superparamagnetic beads on a sensor surface. Antibodies raised against the
drug of interest are linked to magnetic beads. Drug molecules bound to the sensor surface
compete with drugs from the sample for the antibody binding sites. Using morphine as a
model system, different assay protocols were investigated using both well-plate and
cartridge experiments, aiming for an assay at minute time scale. We will present several
competitive assay formats tuned to magnetic nanoparticle labels, compare assays
performed on magnetic biochips and well-plates, and show high-speed drug immunoassay
dose-response data.
D5 – Contributed Paper
SENSING SUBSTRATES MODIFIED WITH GOLD NANOPARTICLE
FILMS
K. Bonroy, F. Frederix, G. Reekmans, H. Jans, R. De Palma, K. Jans, G. Borghs,
IMEC, Kapeldreef 75 Heverlee 3001, Belgium; bonroyk@imec.be
213
A wide range of different materials is used as sensing area of biosensor devices. Most of these
materials form relative flat sensor substrates. Besides the transduction principle, the
sensitivity of affinity-based biosensors is, however, also partially dictated by the amount of
immobilized receptor molecules on the sensor substrate. Three-dimensional (3D) sensor
substrates, created by assemblies of gold nanoparticles, would allow for a larger amount of
immobilized receptor molecules per surface area and could therefore increase the sensor
signal significantly in comparison to standard 2D substrates. In addition, according to
numerous studies, nanoparticle films are very promising for the development of novel
electrical and optical sensors. In this paper, we report on the formation of 3D substrates of
gold nanoparticles on plane gold, quartz and SiO2 substrates using mercapto-silane chemistry.
171
Oral Abstracts
In a first series of experiments, the surface roughness of the resulting 3D gold surfaces was
characterized using SEM, CV and AFM, while the Localized Surface Plasmon Resonance
(LSPR) properties were evaluated using UV/Vis absorption spectroscopy. The sensing
properties of the obtained 3D gold nanoparticles films were further explored on Quartz
Crystal Microbalance (QCM) crystals, SPR slides, interdigitated electrodes (IDE) and LSPR
sensors. Hereby, the sensitivity and the enhancement qualities of the nanoparticles films were
demonstrated for different protein systems such as antibody/antigen and bacterial S-layer
proteins.
D5 – Invited Paper
RADIOLABELED LIPID NANOPARTICLES FOR IMAGING AND
RADIONUCLIDE THERAPY
Beth Goins, University of Texas Health Science Center at San Antonio,
Radiology Dept., San Antonio, TX 78229-3900; goins@uthscsa.edu
214
The goal of this paper is to discuss the uses of radiolabeled lipid nanoparticles, or
liposomes, for scintigraphic imaging and radionuclide therapy. Use of radiolabeled
liposomes as a tool in the development of liposome-based therapeutic agents will also be
discussed. Methods for radiolabeling preformed lipid nanoparticles with single photon
emitting radionuclides for both diagnostic applications (technetium-99m) and radionuclide
therapy (rhenium-186) will be described. Examples of preclinical testing of radiolabeled
liposomes using state-of-the-art dedicated small animal single photon emission computed
tomography (SPECT) and computed tomography (CT) scanner will be given. These
examples include non-invasive tracking and quantitation of the distribution of radiolabeled
liposomes in rat tumor models following injection by intravenous, intratumoral and
intraperitoneal routes.
E3 – Keynote Paper
A NEW PARADIGM FOR LOCAL DRUG DELIVERY: TEMPERATURE
TRIGGERED RELEASE LIPOSOMES FOR ANTI-TUMOR
APPLICATIONS
David Needham, Duke University, CIEMAS, Science Drive, Durham, NC,
27708, USA; d.needham@duke.edu
215
Invented in 1996, the temperature-sensitive liposome, is now in phase 1 human clinical
trials. This presentation will recap earlier work, and present new data that shows
unexpected mechanistic features that make this triggered release system an emerging new
paradigm for local drug delivery, i.e., drug release in the blood stream, where drug gets
access to tumor endothelia as well as to the neoplasm. Drug release from the liposomes
occurs via grain boundary permeabilization when it is heated at its phase transition
temperature, Tm, of 41C. This rate of release of an encapsulated drug like doxorubicin is
enhanced 10X over that of the pure DPPC bilayer by the inclusion of 10mol% lysolipid.
The lysolipid appears to not desorb from the membranes as initially postulated, but remains
in the membranes stabilizing long lasting pores (when held at or close to Tm) through
172
Oral Abstracts
which small molecules and drugs can freely diffuse. This is the basis for the
temperature-triggered nanotechnology for drug release. As for drug action a series of
preclinical studies in window chamber and flank tumors have established that the
mechanism of action is one of vascular shut down because of the unique ability of
Hyperthermia (HT) to release Doxorubicin from the liposomes intravascularly as they pass
through the blood vessels of the mildly heated tumor. Thus, a new target for Doxorubicin
delivered in this unique way appears now to be vascular endothelia, in addition to its
cytotoxicity for cancer cells. We have established that the action of this drug-releasing
liposome in combination with HT has both anti-vascular effects that reduce blood flow and
eventually shut down the blood vessels, as well as anti-cancer cytotoxicity (due in part to
50% of drug delivered to the tumor being bound to DNA in the first hr after
administration).
E3 – Invited Paper
RETROGRADE DELIVERY OF BACTERIAL TOXINS PASSES
THROUGH THE RECYCLING ENDOSOME OF MAMMALIAN CELLS
David Sheff, Department of Pharmacology, Carver College of Medicine,
University of Iowa, 2-570 BSB, Iowa City, IA 52317, USA;
David-Sheff@uiowa.edu
216
All mammalian cells continuously internalize surface receptors and membranes through a
process of constitutive endocytosis. Bacterial toxins, such as shigella toxin and cholera
toxin exploit this process to gain entry into the cytoplasm. Shigella toxin B subunit binds
to plasma membrane globoside and is rapidly delivered to early endosomes. Similarly,
cholera toxin B subunit binds to GM1 gangliosides. Both are delivered in a non-clathrin
dependent pathway to the early endosomes. Both are then targeted to the Golgi apparatus
before reaching the ER. However, the pathway to the Golgi apparatus remains unclear.
Here we find that both toxins pass from early endosomes, through the recycling endosome
en route to the Golgi apparatus. AlF4- treatment unexpectedly results in blockade of
retrograde traffic from the recycling endosome thus trapping bacterial toxins prior to Golgi
entry. Furthermore, in cytoplasts lacking a Golgi apparatus, shigella toxin is capable of
accessing the cytoplasm directly from the recycling endosome without passage through
Golgi apparatus or ER. The ability of the bacterial toxin to bypass the Golgi suggests that
passage through the Golgi may in fact be a result of a host defense mechanism against
bacterial toxins removing toxin from the endosomes before it can exit into the cytoplasm.
These findings also suggest that in cases where Golgi entry is blocked, direct entry into the
cytoplasm, from endosomal comparments, may be enhanced.
E3 – Contributed Paper
POLYELECTROLYTE SELF-ASSEMBLY TO MODIFY SURFACE
PROPERTIES OF PROMAXX INSULIN MICROSPHERES
Ramin Darvari1, Julia Rashba-Step1, Quinmin Lin1, Joan Kelly1,Tatsiana
Shutava2, Yuri Lvov2, Terrence Scott1; 1Epic Therapeutics, Inc., A Wholly
Owned Subsidiary of Baxter Healthcare Corporation, Norwood, MA, USA
217
173
Oral Abstracts
02062; 2Institute for Micromanufacturing, Louisiana Tech University, Ruston,
LA 71272, USA; ramin_darvari@baxter.com
PROMAXX insulin microspheres are the product of a process developed at Epic
Therapeutics, Inc., in which the microspheres are formed by controlled phase separation of
the active agent from aqueous solutions of solubility reducing agents such as polyethylene
glycol. These microspheres contain over 90% of the active agent with a narrow particle
size distribution. This study aimed at developing a process to coat PROMAXX protein
microspheres by means of polyelectrolyte deposition to modify the surface charge, and
dissolution properties of the microspheres. Due to highly soluble nature of the uncoated
microspheres, the polyelectrolyte deposition was performed in aqueous solutions of
solubility reducing agents. The reaction medium consisted of 16% polyethylene glycol
(PEG), 0.7% NaCl, and the polyelectrolyte at 0.15 to 1.5 mg/ml concentration range. The
pH of the medium was ranging between 5.7 to 7.0. The microspheres were incubated for 1
hour in the reaction medium, and the unreacted polyelectrolyte was washed out by medium
replacement. Surface charge modification of the microspheres was shown by comparing
the zeta potential of uncoated PROMAXX insulin mirospheres (-18.0+6.0 mV) with the
coated microspheres using protamine sulfate (19.1+9.1 mV), poly-l-lysine (35.3+3.5 mV),
and poly-l-arginine (37.3+10.2 mV). Confocal microscopy of the microspheres coated
with FITC-labeled polyelectrolytes also confirmed the success of the deposition process.
The in vitro release study of the protamine-coated PROMAXX insulin microspheres
showed a significant reduction of the particles solubility under simulated physiologic
conditions. In vivo performance of the same microspheres was studied in rats receiving 1
IU/kg of the uncoated and coated formulations. The results revealed significant effect of
the coating on the pharmacokinetic parameters of insulin, which in turn extended the
duration of serum glucose depression by over 2.5 fold in comparison with the results
obtained from the uncoated formulation.
E3 – Contributed Paper
POLYMERSOME ENCAPSULATED HEMOGLOBIN (PEH): A NOVEL
TYPE OF OXYGEN CARRIER
Dian R. Arifin, Department of Mechanical Engineering. Monash University,
Clayton, VIC 3800, Australia, dian.arifin@eng.monash.edu.au; and Andre F.
Palmer, Department of Chemical and Biomolecular Engineering, University of
Notre Dame, Notre Dame, IN 46556, USA; apalmer@nd.edu,
dian.arifin@eng.monash.edu.au
218
Bovine hemoglobin (Hb) was encapsulated inside polymer vesicles (polymersomes) to
form polymersome encapsulated Hb (PEH) dispersions. PEHs are 100% surface
PEGylated with longer PEG chains and possess thick hydrophobic membranes as
compared to conventional liposomes. Polymersomes were self-assembled from
poly(butadiene)-poly(ethylene glycol) (PBD-PEO) amphiphilic diblock copolymers with
PBD-PEO molecular weights of 22-12.6 kDa, 5-2.3 kDa, 2.5-1.3 kDa and 1.8-0.9 kDa. The
first two diblock copolymers possessed linear hydrophobic PBD blocks, while the later
possessed branched PBD blocks. PEH dispersions were extruded through 100 and 200 nm
174
Oral Abstracts
pore radii membranes. The size-distribution, Hb encapsulation efficiency, P50,
cooperativity coefficient and methemoglobin (metHb) level of PEH dispersions are
consistent with the values required for efficient oxygen delivery in the systemic
circulation. The influence of different molecular weight diblock copolymers on the
physical properties of PEH dispersions was analyzed. PBD-PEO copolymers with
molecular weights of 22-12.6 kDa and 2.5-1.3 kDa completely dissolved in aqueous
solution to form polymersomes, while the other two copolymers formed a mixture of solid
copolymer precipitates and polymersomes. PEHs self-assembled from 22-12.6 kDa and
2.5-1.3 kDa PBD-PEO copolymers possessed Hb loading capacities greater than
PEG-LEHs, PEGylated actin-containing LEHs and non-modified LEHs, although their
sizes were smaller and their hydrophobic membranes were thicker. The Hb loading
capacities of these polymersomes were also higher than those of lipogel encapsulated
hemoglobin particles and nanoscale hydrogel encapsulated hemoglobin particles. PEH
dispersions exhibited average radii larger than 50 nm and exhibited oxygen affinities
comparable to human erythrocytes. Polymersomes did not induce Hb oxidation. The
interaction between Hb and the membrane of 2.5-1.3 kDa PBD-PEO polymersomes
improved the monodispersity of these particular PEH dispersions. These results suggest
that PEHs could serve as efficient oxygen therapeutics.
E3 – Invited Paper
LIPOSOMAL DELIVERY OF ALL-TRANS-RETINOIC ACID:
CHALLENGES AND RESULTS
Krzysztof Dziewiszek, Cristina Musselli, David O’Donnell, Lavesh Gwalani,
Daniel Levey, Roman M. Chicz, Antigenics Inc., 3 Forbes Rd., Lexington, MA
02421 kdziewiszek@antigenics.com
219
Tretinoin (all-trans Retinoic acid) is a known anticancer agent used in the treatment of
Acute Promyelocytic Leukemia (APL) to cause maturation of promyelocytic cells,
triggering a repopulation of bone marrow and peripheral blood with normal hematopoietic
cells. It is currently supplied as Vesanoid® in gel capsules for oral administration.
However, its oral administration is hampered by erratic plasma concentrations and in
continuous treatment, by a progressive decrease in plasma concentration. Due to
potentially severe side effects (RA-APL syndrome), Vesanoid’s use has to be monitored
and it should be administered in a facility with available supportive services to manage the
cases with severe intolerance. This greatly diminishes the benefits of oral administration.
On the other hand, parenteral formulation, which would circumvent the plasma
concentration variability, is difficult to develop due to minimal water solubility of
tretinoin. Liposomes are well known vehicles suitable for lipophilic drugs that do not
adversely affect the activity of Active Pharmaceutical Ingredient (API) and this technology
was proven in the cases of doxorubicin and amphotericin B. Liposomal formulation of
tretinoin, which contains Dimyristoylphosphatidylcholine (DMPC) and small amounts of
soybeen oil has been developed. Administration of this formulation circumvents problems
resulting from the oral drug’s availability and its toxicity, which is associated with the
presence of free tretinoin. Biological activity of two tretinoin formulations will be
discussed.
175
Oral Abstracts
E3 – Invited Paper
TRANSFERRIN-LOADED NIDO-CARBORANE LIPOSOMES:
SYNTHESIS AND INTRACELLULAR TARGETING TO SOLID TUMORS
FOR BORON NEUTRON CAPTURE THERAPY
Hiroyuki Nakamura, Yusuke Miyajima, Department of Chemistry, Faculty of
Science, Gakushuin University, Tokyo 171-8588, Japan; Shinichiro Masunaga,
Koji Ono, Research Reactor Institute, Kyoto University, Osaka, 590-0494,
Japan; Yasuhiro Kuwata, and Kazuo Maruyama, Biopharmaceutics, School of
Pharmaceutical Science, Teikyo University, Kanagawa 199-0195, Japan;
hiroyuki.nakamura@gakushuin.ac.jp
220
The nido-carborane lipid 2 which has a double-tailed alkyl moiety was synthesized from
heptadecanol by 5 steps. Analysis in a transdmission electron microscope by negative
staining with uranyl acetate showed that the lipid 2 formed a stable vesicle in which calcein
was encapsulated. Furtheremore, the lipid 2 formed a stable boron liposome at 25% molar
ratio toward DSPC with cholesterol after sizing by a extruder. Transferrin was able to be
introduced on the surface of the boron liposome (Tf-PEG-CL-liposome) by coupling of
transferrin to PEG-CO2H moieties of PEG-CL liposomes. The biodistribution of
Tf-PEG-CL-liposome, in which 125I-thylaminyl inulines were encapsulated, exhibited that
Tf-PEG-CL-liposome was accumulated into tumor tissue and stayed for a prolonged time
enough to increase a ratio of the tumor/blood concentration, although PEG-CL-liposome
was gradually released from tumor tissue along with the time course. The high
accumulation and long retention time in tumor tissue was due to a transferrin
receptor-mediated endocytosis and 22 ppm of 10B concentration in tumor tissue was
achieved by injection of 10B-enriched Tf-PEG-CL-liposome at 7.2 mg 10B/kg in
tumor-bearing mice at 72 h after administration of the liposome. The mice were
anesthetized with sodium pentobarbital solution, placed in an acrylic mouse holder, where
whole bodies of mice except the tumor-implanted leg were shielded with the acrylic resin,
and irradiated in the KUR atomic reactor for 37 min at a rate of 2 x 1012 neutrons/cm2. The
average of survivals of mice without treated with the Tf-PEG-CL-liposome was 21 days,
whereas that of mice treated with the Tf-PEG-CL-liposome was 31 days. The longer
survivals were observed in mice treated with the Tf-PEG-CL-liposome and one of them
survived for 52 days after BNCT.
J2 – Keynote Paper
NUCLEIC ACID MICROSPHERES FOR TYPE 1 DIABETES
INTERVENTION
Larry Brown1, Kimberly Gillis1, Joseph Worrall1, Nick Giannoukakis 2, Janet
Knox1, Jennifer Machen2 1Epic Therapeutics, Inc., A Wholly Owned
Subsidiary of Baxter Healthcare Corporation, Norwood, MA, 02062,
2
University of Pittsburgh School of Medicine, Diabetes Institute, Rangos
Research Center, Pittsburgh, PA, 15213, USA; larry_brown@baxter.com
221
Type 1 diabetes mellitus occurs as a result of the autoimmune destruction of the insulin
producing beta cells of the pancreas. This is mediated by macrophages and T cell-mediated
176
Oral Abstracts
destruction of the beta cells. CD40, CD80 and CD86 surface cell antigens expressed on the
dendritic cells (DC) are crucial regulators of T cell activation. Our goal was to form
antisense (AS)-oligonucleotide PROMAXX microspheres targeting the primary
transcripts of CD40, CD80 and CD86 in order to prevent autoimmune insulin-dependent
diabetes in the NOD mouse. Three phosphothioated AS-oligonucleotides were dissolved in
an aqueous solution and combined with polylysine and water-soluble polymers such as
polyethylene glycol and polyvinylpyrollidone. The solutions containing the polymer, the
antisense oligonucleotides and the polycation were incubated at 58 to 70°C, and cooled to
23°C. Excess polymer was removed by washing with deionized water. The microspheres
were about 1 to 3 microns in diameter by light scattering. In-vivo studies treated one group
of NOD mice with DC that had been treated ex-vivo with AS-oligonucleotides directed
against CD40, CD80 and CD86. Group 2 NOD mice were injected with
AS-oligonucleotide PROMAXX microspheres. Untreated controls were injected with DC
not exposed to AS-oligonucleotides. In vivo results showed that all of the untreated DC
control mice developed diabetes by 23 weeks. 20% of the DC AS-oligonucleotide treated
mice remained diabetes-free at 40 weeks. 71% of the AS-oligonucleotide PROMAXX
microsphere treated group remained diabetes free at 40 weeks. This study showed that the
PROMAXX delivery system enabled superior in-situ delivery of the AS-oligonucleotides
and significantly enhanced the therapeutic efficacy of diabetes suppression. The
microspheres provided effective uptake of AS-oligonucleotides by DC resulting in the
prevention of diabetes in NOD mice by inducing immune tolerance. The PROMAXX
AS-oligonucleotide microsphere approach is a promising new preventative treatment for
Type 1 diabetes and other autoimmune diseases.
J2 – Invited Paper
DEVELOPMENT OF NANOTRANSFECTION COMPLEXES FOR
SYSTEMIC TREATMENT OF CANCER
Sean M. Sullivan, Department of Pharmaceutics, University of Florida
College of Pharmacy, Gainesville, FL 32610-0494, USA;
sullivan@cop.ufl.edu
222
Binding of plasmid DNA to cationic amphiphiles converts the plasmid from a random coil
with an approximate radius of gyration of 100nm to a toroid composed of multiple plasmid
DNA molecules with a 80 nm radius. This condensed DNA form the basis for the
nanoplex. Systemic administration of nanoplexes results in distribution of plasmid DNA
into the major organs, including the lung, liver, spleen, heart, muscle and kidneys with the
lungs yielding the highest level of gene expression followed by the heart, muscle and
spleen. Using this strategy to treat vascularized tumors will require selective gene transfer
to the tumor and avoid uptake or at least expression in the non-tumor tissue. In vivo studies
have also shown that the nanoplexes can not extravasate out of the blood stream or if so,
not very efficiently. Hence, the tumor vasculature is the primary target for treating the
cancer that will lead to the destruction of the vasculature itself and/or secretion of cytotoxic
proteins into the tumor from the tumor endothelial cells resulting in tumor cell killing.
Coating the surface of the nanoplexes with peptides that bind to receptors on the tumor
endothelial cells can achieve selective gene transfer to the tumor cells. Peptides that bind
177
Oral Abstracts
to CXCR4, a chemokine receptor for stromal derived factor-1 (SDF-1), and basic
fibroblast growth factor receptor (bFGFR) with nanomolar binding affinity have been
derivatized to phospholipid analog and incorporated into nanoplexes composed of a
dilaurylspermine coformulated with a mixture of lyso-phosphatidylcholine,
monoacylglycerol and fatty acid. CXCR4 is expressed on proliferating endothelial cells
and the receptor density is dramatically increased in a positive autocrine feedback loop by
vascular endothelial derived growth factor (VEGF). Receptor mediated transfection of
both endothelium and brain cancer cells are demonstrated using a combination of tissue
culture and blood vessel arteriograph organ cultures. These peptide targeted nanoplexes
will deliver a cytotoxic gene and the expression is controlled by a proliferating endothelial
cell promoter to further restrict expression to the tumor vasculature. A cytotoxic gene has
been engineered to yield a secreted gene product that is composed of a cytotoxic domain
and a membrane permeability domain. The cytotoxic domain is a 14 amino acid sequence
derived from P19ARF that binds Mdm 2 and inhibits ubiquination of proteins, including
P53, a tumor suppressor protein. The membrane permeability domain is also composed of
a 14 amino acid sequence derived from HIV-Tat. Peptide modeling studies of the
expressed gene product yielded an IC50 of 3 uM. Transfection of human brain cancer cells
with an expression plasmid encoding the bifunctional cytotoxic protein resulted in 50%
cell death with only 8% of the cells transfected. This could be increased to 90% cell killing
when transfection efficiencies were increased to 18%. Furin, a protease secreted by both
human and rat brain cancer cells was shown to hydrolyze the cytotoxic gene product into
discrete bands thus being a potential inactivator. Addition of a recombinant furin inhibitor
increased cell killing as a function of dose with the highest dose yielding a 3 fold increase
in cell killing. These studies have identified and characterized a biochemical and molecular
biological targeting system for treatment of vascularized tumors, specifically brain cancer.
A synthetic gene has been created that kills cells through a bystander effect thus increasing
the therapeutic effectiveness by impacting the neighboring untransfected cells surrounding
the transfected endothelial cells.
J2 –Contributed Paper
ENHANCEMENT OF THE EFFICIENCY OF NON-VIRAL GENE
DELIVERY BY APPLICATION OF PULSED MAGNETIC FIELD
S.W. Kamau, P.O. Hassa, B. Steitz, A. Petri-Fink, H. Hofman, M. Hofman, B.
von Rechenberg, and M.O. Hottiger, Institute of Veterinary Biochemistry and
Molecular Biology, University of Zurich, Winterthurerstr. 190, CH-8057
Zurich, Switzerland; kamau@vetbio.unizh.ch
223
Non-viral gene vectors have several advantages, however, the transfection efficiencies
remain lower than those with viral vectors and a need exists to enhance the efficiency of
non-viral gene delivery. Superparamagnetic nanoparticles (SPIONs) based on iron oxide,
have an advantage in gene delivery since their combination with magnets that can draw
particles to a desired location and keep them at a specific site. We explore the use of
smaller polyethylenimine (PEI) coated SPIONs, use of novel shorter DNA fragments
(PCR products) instead of plasmids and application of a pulsating magnetic field, on
enhancing green fluorescent protein (GFP) gene delivery. Our results show that smaller 50
178
Oral Abstracts
nm PEI coated SPIONs were as effective as the larger 200-250 nm nanoparticles, however
they required more time to sediment on the cells after exposure to a magnetic field. The
transfection rates achieved with SPIONs within 5 min were significantly higher than those
achieved with conventional transfection methods. This was also observed when novel PCR
products containing only the sequence of the gene of interest, were used. The application of
a pulsating magnetic field, after sedimentation of the particles with a static magnetic field
increased the transfection efficiency significantly, over the magnetofection. In conclusion,
we show that PCR products are effective gene vectors when coupled to SPIONS and are
attractive alternatives to plasmids. The application of a pulsating magnetic field enhances
the already high transfection rates in presence of static magnet. Smaller SPIONS are as
effective as large particles and would be more suited in future in vivo studies.
J2 – Invited Paper
SYNTHESIS, CHARACTERIZATION & TRIGGERED DETHREADING
OF CYCLODEXTRIN-POLYETHYLENE GLYCOL POLYROTAXANES
BEARING CLEAVABLE ‘CLICK’ ENDCAPS
David H. Thompson, Scott Loethen, Department of Chemistry, Purdue
University, 560 Oval Drive, West Lafayette, IN 47907, USA; Tooru Ooya and
Nobuhiko Yui, Japan Advanced Institute of Science and Technology, School
of Materials Science, 1-1 Asahidai, Nomi, Ishikawa, 923-1292, Japan;
davethom@purdue.edu
224
We report the synthesis, characterization and degradation kinetics of three α-cyclodextrin
(α-CD)-polyethylene glycol (PEG) polyrotaxanes with endcapping groups that were
installed using Cu (I)-catalyzed Huisgen cyclization (a.k.a., “click” reaction). PEG1500,
aminated at the α- and ω-termini of the polymer with azidoacetic acid, was used to thread
α-CD onto the polymer chain to form a polypseudorotaxane. The polypseudorotaxane was
then endcapped in up to 82% yield with three different substituents to provide
polyrotaxanes that were either acid-, base- or fluoride-sensitive. NMR, GPC, AFM, and
XRD were used to characterize the polyrotaxanes. Turbidity analysis was used to monitor
their dethreading rates upon exposure to mild deprotection conditions. Rates of
solubilization triggered by endcap hydrolysis and polyrotaxane dethreading were found to
be pH dependent. The vinyl ether endcapped polyrotaxane is stable at pH 7 for 16 h, but is
solubilized at approximately 0.0211 min-1 at pH 4. The ester-endcapped polyrotaxane is
rapidly solubilized at pH 12.1 with a rate of 0.0122 min-1. These results show that
pH-triggerable polyrotaxanes can be readily and efficiently prepared from
polypseudorotaxanes in high yield by Huisgen cyclization of azido- and alkynyl-modified
precursors in the presence of Cu(I).
J2 –Contributed Paper
TARGETED NEURONAL DELIVERY OF A SINGLE ANTIVIRAL SIRNA
PROTECTS MICE AGAINST ENCEPHALITIS CAUSED BY TWO
DISTINCT FLAVIVIRUSES
Sang-Kyung Lee, Department of Bioengineering, Hanyang University, 17
225
179
Oral Abstracts
Haengdang-dong Seongdong-gu, Seoul 133-791, Korea; Priti Kumar,
Premlata Shankar and N. Manjunath Swamy,
CBR Institute for Biomedical Research, Harvard Medical School, 800
Huntington Ave, Boston, Massachusetts 02115, USA;
sangkyunglee@hanyang.ac.kr, swamy@cbr.med.harvard.edu
Japanese encephalitis (JE) and West Nile (WN) viruses are neurotropic flaviviruses that
can cause acute encephalitis with a high degree of fatality. Infections by diverse
neurotropic flaviviruses are clinically indistinguishable and currently there are no effective
drugs to treat these infections. Thus it is important to develop therapeutic approaches that
are effective against multiple viruses within and across the flaviviral species. In this study,
we employed RNA interference (RNAi) targeting a cross-species conserved sequence in
the flaviviral genome as a broad-based intervention against flavivirus infection. By using a
lentiviral vector pseudotyped with the rabies virus glycoprotein (RVG) that enabled
specific and targeted delivery of antiviral siRNA to neurons we were able to completely
abrogate flaviviral replication in the neuroblastoma cell line, Neuro 2a. Moreover, a single
administration of vector-delivered short-hairpin RNA was able to completely protect mice
against a lethal intracranial challenge with as high as 50LD50 of virus. RVG-mediated
targeting also resulted in better levels of protection compared to the conventional methods
of delivery using the Vesicular Stomatitis virus glycoprotein, possibly due to better
retro-axonal spread attributed to RVG. As a further demonstration of the feasibility of an
RNAi-based therapy for viral encephalitis, we used cationic lipid formulations that
mediate effective brain delivery of short interfering (si)RNA. A single intracranial
application of lipid-complexed siRNA targeting conserved viral sequences before viral
challenge and more importantly, as late as 18 hours after viral challenge was sufficient for
protection of mice against lethal encephalitis induced by both JEV and WNV. These
results demonstrate the practicality of using lipid-based delivery of single siRNA targeting
a conserved sequence as a broad-based therapeutic strategy against multiple related
viruses. Efforts are currently underway towards developing a nanoparticle-mediated
approach for targeted brain delivery following peripheral administration of this common
siRNA.
J2 – Invited Paper
RECEPTOR-MEDIATED GENE DELIVERY USING CHITOSAN
DERIVATIVES IN VITRO AND IN VIVO
Chong Su Cho, Tae Hee Kim, School of Agricultural Biotechnology, Seoul
National University, Seoul 151-742, South Korea; Hua Jin, Hyun Woo Kim,
and Myung-Haing Cho, College of Veterinary Medicine, Seoul National
University, Seoul 151-742, South Korea; chocs@plaza.snu.ac.kr
226
Chitosan has been considered to be a good candidate for gene delivery system, since it is
already known as a biocompatible, biodegradable, and low toxic material with high
cationic potential. However, low specificity and low transfection efficiency of chitosan
need to be overcome prior to clinical trial. In this study, we focused on the chemical
modification of chitosan for enhancement of cell specificity and transfection efficiency. To
180
Oral Abstracts
induce the receptor-mediated endocytosis into liver cells, chitosan was coupled with
lactobionic acid (LA) bearing galactose group as the specific ligand to asialoglycoprotein
receptor (ASGP-R). Also, mannosylated chitosan (MC) was prepared by coupling chitosan
with mannopyranosylphenylisothiocyanate bearing mannose group to induce the
receptor-mediated endocytosis into dendritic cells (DCs). And their physicochemical
properties, morphology, cytotoxicity, and transfection efficiency of the complexes in vitro
and in vivo were studied. The potential of antitumor effect in vivo by using MC for delivery
of IL-12 genes was also evaluated. Transfection efficiency of GC/DNA complex into
HepG2 which has ASGP-R was higher than that into HeLa without ASGP-R. MC had low
cytotoxicity and exhibited much enhanced gene transfer efficiency on the macrophage cell
lines compared with chitosan itself. Increased IL-12 production by DC induced increase of
IFN-γ production. In vivo study shows that intratumoral delivery of IL-12 genes using MC
is an effective method of generating antitumor immunity. In conclusion, it is expected that
relatively non-toxic GC and MC is suitable for repeated administration to maintain
sustained gene expression, thereby opening the possibility for cancer gene therapy.
J2 – Invited Paper
NANOPARTICLE-MEDIATED DELIVERY OF TUMOR SUPPRESSOR
GENES
Rajagopal Ramesh 1, Lin Ji 1, Began Gopalan 1, Jack A. Roth 1, Louis A.
Zumstein2, 1University of Texas MD Anderson Cancer Center, Houston, TX, 2
Introgen Therapeutics, Houston, TX 77030, USA; L.Zumstein@introgen.com
227
Nanoparticle delivery of tumor suppressor genes is a promising approach for the treatment
of cancer. Our nanoparticles comprise a therapeutic tumor suppressor gene surrounded by
a lipid bilayer. This lipid bilayer allows for systemic delivery of gene therapies, without
generating an immune response, as well as potential modification of the surface layer of the
nanoparticle. We have developed a novel nanoparticle which delivers the Fus1 tumor
suppressor gene, which has completed preclinical testing and is undergoing clinical testing
in cancer patients. Fus1 was identified as a tumor suppressor gene in a region of
chromosome 3p21 which is frequently deleted in human lung and breast cancers. FUS1
protein is frequently not expressed in lung cancer, and expression of FUS1 protein induces
apoptotic cell death in cancer cells. Sequence analysis suggests that FUS1 has a protein
kinase A domain, a protein-protein interaction domain, and a myristolyation domain. The
lipid is a 1:1 (molar) mixture of DOTAP and cholesterol. The formulation steps, which
include extrusion, result in a DNA-lipid nanoparticle with a unique bilamellar vase-like
structure, which is taken up by cells by phagocytosis. In animal studies this nanoparticle
allowed for high efficiency of delivery and a broad tissue distribution. The nanoparticle is
also not immunogenic, a potential advantage over viral gene therapy vectors. In animal
models of cancer, nanoparticle FUS1 demonstrated potent antitumor activity in solid
primary tumors (delivered intratumorally) and metastatic lesions (delivered
intravenously); antitumor activity was demonstrated by the complete inhibition of growth
of solid tumors, a dramatic decrease in the number of metastatic lesions, and increased
survival of the mice. A Phase 1 intravenous dose-escalating safety study is underway at
University of Texas MD Anderson Cancer center with nanoparticle Fus1 in non-small cell
181
Oral Abstracts
lung cancer patients; to date nanoparticle-Fus1 is well tolerated, and the dose-escalation is
continuing.
A6 – Invited Paper
GLUCOSE-SENSING MICROGELS
Todd R. Hoare and Robert H. Pelton, McMaster Centre for Pulp and Paper
Research, Department of Chemical Engineering, McMaster University, 1280
Main St. W., Hamilton, Ontario, Canada L8S 4L7; hoaretr@mcmaster.ca;
peltonrh@mcmaster.ca
228
Hydrogels which can reversibly respond to both physical and chemical stimuli have great
potential as switchable chemoselective probes and feedback-controlled delivery vehicles
for drug or macromolecule transport. Microgels with similar functionality are even more
attractive since they respond much faster and more predictably to external stimuli and can
be administered readily via flow processes.
We have synthesized amphoteric
poly(N-isopropylacrylamide) (PNIPAM)-based microgels with covalently tethered
phenylboronic acid (PBA) functional groups. Phenylboronic acids form reversible
covalent complexes with carbohydrates containing cis-diol groups, such as glucose; thus,
PBA-microgels are tunably responsive to pH, temperature, ionic strength, and glucose
concentration. The thermal phase transition of the PNIPAM backbone can be used to
amplify the electrostatics-driven gel swelling induced by glucose binding, while the
zwitterionic nature of the microgel surface maintains the colloidal stability and glucose
responsiveness of the microgels in the high-temperature, high-salt physiological
environment. The amphoteric nature of the microgels also permits the design of microgels
which can both swell and shrink in response to increases in the glucose concentration
according to the pH of the medium. The potential applications of such microgels as
turbidimetric glucose sensors, “smart”, self-regulating insulin-delivery vehicles for
diabetes treatment, and selective cell bioflocculants have been demonstrated.
A6 – Invited Paper
PEPTIDE NANOPARTICLES FOR MEDICAL APPLICATIONS: NOVEL
DRUG TARGETING, DELIVERY AND VACCINATION STRATEGIES
Alexandra Graff, Senthilkumar Raman, Gia Machaidze, Ariel Lustig, M.E.
Müller Institute for Structural Biology, Biozentrum, University of Basel,
Switzerland; and Peter Burkhard, The Institute of Materials Science,
University of Connecticut, 97 North Eagleville Road, Storrs, CT 06269-3136,
USA; peter.burkhard@uconn.edu
229
Artificial particulate systems such as polymeric beads and liposomes are finding multiple
applications in drug delivery, drug targeting, antigen display, vaccination, and other
technologies. Here we describe the structure-based design of a novel type of nanoparticles
with regular polyhedral symmetry and a diameter similar to small viruses, which
self-assemble from single polypeptide chains. Each peptide chain is composed of two
protein domains with trimeric and pentameric oligomerization states that are joined into
182
Oral Abstracts
one single peptide chain by a short linker segment. E.g. a de-novo designed trimeric
coiled-coil domain is joined to the pentameric coiled-coil domain of COMP to give a
nanoparticle with a size of about 17 nm. These computer designs are verified by structural
and biophysical analyses including electron microscopy, analytical ultracentrifugation,
CD-spectroscopy, dynamic light scattering and many more. These nanoparticles represent
a novel type of nanomaterial ideally suited as drug targeting and delivery systems. Since
they are composed of peptides they are fully biocompatible and biodegradable.
Furthermore, since they are built from protein domains this allows for a highly specific
design in terms of shape, size and stability of the nanoparticles. Their modular composition
enables an easy and rapid design and generation of different combinations of drugs and
targeting entities. Hence these nanoparticles can be used as a drug targeting toolbox:
different drugs (e.g. radioisotopes, doxorubicin, etc.) can be combined with different
targeting entities (e.g. somatostatin, bombesin, etc.) in an easy and straight-forward
manner. Furthermore, such nanoparticles with regular polyhedral symmetry represent an
ideal repetitive antigen display system. Surface proteins of pathogens or fragments of such
proteins can easily be engineered into the peptide sequence of the nanoparticle. Notably,
the surface proteins of enveloped viruses contain a trimeric coiled-coil sequence essential
for their cell penetration mechanism. For example, by extending the trimeric coiled-coil of
the nanoparticle by the respective coiled-coil sequences of HIV, influenza, Ebola, or
another enveloped virus, a subunit vaccine against these viruses can be designed. Finally,
since they are composed of small protein oligomerization domains they are easy to
synthesize by standard recombinant E. coli protein expression systems. The vaccines can
be produced in one single manufacturing process without the need of any additional
chemical modifications and, as opposed to most virus like particles, they are stable without
the need of DNA packaging inside.
A6 – Contributed Paper
PREPARATION OF MONOFUNCTIONAL GOLD
NANOPARTICLE-DENDRIMER (PAMAM) CONJUGATES BY
COVALENT APPROACH
Qiu Dai, James G. Worden, Xiong Liu, Jinhai Wang, Jianhua Zou, and Qun
Huo, Nanoscience Technology Center and Department of Chemistry,
University of Central Florida, 12424 Research Parkway Suit 422, Orlando, FL,
USA; E-Mail: qhuo@mail.ucf.edu
230
The synthesis and study of gold nanoparticles (NPs) is a major area of current
nanomaterials research. Due to their unique optical and electrical properties, gold
nanoparticles may potentially be applied in catalysis, sensing, environmental, Surface
Enhanced Raman Scattering, nonlinear absorption processes, and optoelectronics. There
are two significant challenges which first must be overcome; the first is the synthesis of the
gold nanoparticles with the proper size and surface functionality. The second is how to
assemble the gold nanoparticles together with desired properties. Recently we report our
work on the preparation of monofunctional gold nanoparticles using a solid phase
synthesis method. Compared to multifunctional gold nanoparticles, these nanoparticles
offer greater versatility for the preparation of more complex nanostructures. Gold
183
Oral Abstracts
nanoparticles with a single functional surface group may be treated like regular molecules
and used in traditional organic chemistry reactions. Herein we report that gold
nanoparticles-dendrimer conjugate clusters were prepared by the covalent coupling of
monofunctional gold nanoparticles with a generation 5 PAMAM dendrimer.
Monocarboxylic group modified gold nanoparticles with an average core diameter of 2.8
nm were covalently coupled with 5 PAMAM dendrimer which has 128 primary amine
groups on its surface. TEM images show that most of the conjugates consisted of 5-10
nanoparticles with a diameter of 10-13 nm. This work demonstrates that the potential of
convent bond chemistry in the bottom-up approach towards the nanomaterials
development. This approach can be readily extended to the fabrication of other types of
more sophisticated nanomaterials with well-controlled structures and properties for
biomedical applications such as drug delivery and molecular imaging purposes.
A6 – Invited Paper
CHLOROTOXIN-BOUND SUPERPARAMAGNETIC NANOPARTICLES
FOR BRAIN TUMOR DIAGNOSIS AND THERAPEUTICS
Omid Veiseh, Conroy Sun, Jonathan Gunn, Nathan Kohler, Narayan
Bhattarai, Donghoon Lee, Raymond Sze, Richard.Ellenbogen, Andrew
Hallahan, Jim Olson, Miqin Zhang, Department of Materials Science and
Engineering, University of Washington, Seattle, WA 98195, USA;
mzhang@u.washington.edu
231
A bifunctional nanoconjugate for targeting gliomas and inhibiting tumor migration was
developed by coating iron oxide superparamagnetic nanoparticles with chlorotoxin (Cltx).
The preferential binding of Cltx-conjugated nanoparticles to glioma cells, as compared to
dextran-coated nanoparticles, was evaluated qualitatively by magnetic resonance imaging
(MRI) and quantitatively by inductively coupled plasma atomic emission spectroscopy
(ICP-AES). The specificity of glioma-targeting was evaluated through a comparison of the
nanoparticle binding to glioma cells that express matrix metalloproteinase 2 (MMP-2)
versus healthy cells that do not express detectable MMP-2. The ability of the nanoparticle
conjugate to inhibit cell migration was demonstrated by the matrigel invasion test in which
Cltx-conjugated nanoparticles showed similar efficacy to free Cltx at a concentration lower
than that of free Cltx peptide. This indicates that the Cltx retained its bioactivity after
conjugation to the nanoparticle and that the nanoparticles enhanced the cellular uptake and
retention of Cltx in the target cells. The Cltx conjugated nanoparticles can be potentially
used for highly sensitive detection of glioma tumors and targeted therapy in the central
nervous system.
A6 – Invited Paper
FUNCTIONALIZATION OF NANOPARTICLES FOR DISEASE
DETECTION AND TARGETED DRUG DELIVERY.
Lucienne Juillerat-Jeanneret, Feride Cengelli, University Institute of
Pathology, Bugnon 25, 1011, Lausanne, Switzerland; Heinrich Hofmann, Alke
Petri-Fink, EPFL, 1015, Ecublens, Switzerland; Justyna Grzyb, Stephen
232
184
Oral Abstracts
Hanessian, University of Montreal, Canada; lucienne.juillerat@chuv.ch
Super Paramagnetic Iron Oxide Nanoparticles (SPIONs) combined with MRI are under
clinical evaluation to enhance disease detection. A major improvement would be to link
therapeutic drugs or targeting agents to the SPIONs to achieve targeted drug delivery,
either at the cell surface or intracellularly, together with active and selective disease
detection, without inducing cell reaction. Our objectives are to define the characteristics of
SPIONS able to achieve cell-specific interaction with tissue structures and to develop the
necessary chemistry to achieve these goals. Our system consists in an ironoxide core (9-10
nm diameter) coated either with dextran or various functionalized polyvinylalcohol (PVA).
We investigated the cellular uptake, the cytotoxicity and the interaction of these various
nanoparticles with tumor cells in aggregate cultures, tumor-associated stromal cells and
brain-derived endothelial cells, microglial cells and differentiating 3-dimensional
aggregates. None of the nanoparticles coated with dextran or the various PVAs was
cytotoxic or induced the production of the inflammatory mediator NO used as a reporter
for cell activation. Only aminoPVA-SPIONs were taken up by the cells, but did not invade
cell aggregates lower than the first cell layer or induced microglial cell activation and NO
production in the aggregates. Fluorescent aminoPVA-SPIONs derivatized with a
fluorescent reporter molecule and confocal microscopy demonstrated intracellular uptake
by microglial cells. Therefore functionalized aminoPVA-SPIONs represent biocompatible
potential vector systems for drug delivery which will not produce massive tissue invasion
and can be combined with MRI detection of active lesions in diseases. In order to develop
therapeutics-derivatized-SPIONs and to couple defined molecules for targeted detection
and drug-delivery purposes, we have designed and synthesized a multivalent linker, to
which drugs are covalently coupled via a biologically labile linkage before the preparation
of derivatized SPIONs.
A6 – Contributed Paper
PRECIPITATION OF AN AMORPHOUS PHARMACEUTICAL SOLID
Hsien-Hsin Tung, Elizabeth Kwong, Aaron Cote, Brian Johnson, Cindy
Starbuck, Alex Chen, Chad Dalton, Sophie-Dorothee Clas, Wayne Mullett,
Robert Papp, Bernard Cote, Xiaoyi Gong and Theresa Natishan, Merck
Company, Rahway, NJ 07065; hsien_hsin_tung@merck.com
233
Amorphous solids (glasses) can play an important role in improving bioavailability,
especially for water insoluble pharmaceutical compounds. A traditional method for the
generation of amorphous solids is via precipitation. In this study, we investigate the
confined impinging jet mixer for the precipitation of an amorphous pharmaceutical solid.
Impinging jet provides scalable rapid micro-mixing between the batch solution (DMSO)
and anti-solvent (water), which generates a controlled local high supersaturation
environment for the precipitation. Conversion of the amorphous solid to crystalline solid
during the precipitation was effectively minimized by operating the system near the
freezing point of solvent mixture without adding additives. The process was scaled up
successfully from the grams scale to the hundred grams scale. Physically, the resulting
amorphous solid shows a 30-fold increase in surface area (amorphous: 37.9 m2/gram vs.
185
Oral Abstracts
crystalline 1.3 m2/gram), a 15-fold increase of aqueous solubility (amorphous 0.5 μg/mL
vs. crystalline 0.03 μg/mL) and a 75-fold increase of solubility in DMSO/water 1/1 solvent
mixture (amorphous 0.23 mg/ml vs. crystalline 0.003 mg/ml). The amorphous impinging
jet precipitate further shows a significant improvement of in-vivo performance with a
10-fold increase in bioavailability. The dry amorphous solid with a high glass transition
temperature of 150°C, is physically and chemically stable under ambient conditions and
was found to be acceptable for development into a solid oral dosage form to support Phase
I studies.
A6 – Contributed Paper
SEMICARBAZIDE FUNCTIONALIZED SILICATE NANOPARTICLES
FOR PEPTIDE LIGATION
Monique Smaïhi, Tristan Doussineau, IEM, UMR 5635
CNRS-ENSCM-UM2, 1919 route de Mende, 34 193 Montpellier Cedex 5,
France ; and Ouafâa El-Mahdi, Rémi Desmet, Christophe Olivier, Oleg
Melnyk, Biological Institute of Lille, UMR 8525 CNRS/Université de Lille
2/Institut Pasteur de Lille, 1 rue du Pr Calmette 59021 Lille Cedex, France ;
and Jean-Olivier Durand, CMOS, UMR 5637, case 007-Université Montpellier
II, Place Eugène Bataillon, 34095 Montpellier Cedex 05 France;
smaihi@iemm.univ-montp2.fr
234
The versatility of silica in synthesis aspects as well as surface modifications offers a great
advantage to the use of the material in bioanalysis. Therefore, we have used monodisperse
silicate nanoparticles to develop a site-specific ligation method which enables the control
of the biomolecule orientation at the solid–liquid interface. Two types of zeolite colloidal
nanoparticles were used for peptide anchoring : zeolite beta which posses a Si/Al ratio of
25 and silicalite-1 which is a fully silicic material. Zeolite-type materials are microporous
silicate with pores of a well-defined size ranging from 2 to 20 Å. This discrete pore system
gives molecular sieve properties to these materials. Semicarbazide-functionalized (SC)
silicate colloids have been prepared for the site-specific ligation of alpha oxo aldehyde
(COCHO)-modified polypeptides. The obtained colloidal suspensions have been
characterized by complementary techniques providing information on the size distribution,
morphology, chemical nature of the grafting and porosity of the particles. The specificity
of the particles surface for the SC group has been studied by fluorescence spectroscopy
with two peptides labelled with rhodamine. The first peptide bares a COCHO
functionality, which should bind covalently with the semicarbazide surface. The second
peptide bares an amine end-group which should interact by non specific adsorption with
the surface. The results demonstrated that the peptide/colloids reactivity is dramatically
influenced by the chemical composition of the particles surface. Indeed, while zeolite beta
(aluminosilicate) particles react indifferently with the two peptides, silicalite particles
(pure silicate) anchor exclusively the peptide bearing the COCHO functionality. This
particular physisorption phenomenon of zeolite beta, is attributed to the aluminum atoms
present at the particles surface which have a specific affinity for peptides. Since fluorescent
molecules have been confined in the microporous zeolite cavities, these nanoparticles
could find applications in immunodiagnostics and drug delivery.
186
Oral Abstracts
A6 – Contributed Paper
INTEGRATION OF MAGNETIC NANOPARTICLES INTO
TEMPERATURE RESPONSIVE HYDROGEL SYSTEMS
Reynolds A. Frimpong and J. Zach Hilt
Department of Chemical and Materials Engineering, University of Kentucky
Lexington, KY, USA; frimpr@uky.edu
235
Magnetic nanoparticles have been integrated with temperature responsive hydrogel
systems to form composites expected to have wide applicability in various biomedical
applications. These systems particularly show great promise as active components of
micro- and nanoscale devices. Several N-isopropylacrylamide systems were synthesized
by UV free radical polymerizations with varying crosslinking densities and lengths based
on ethylene glycol dimethacrylate, tetraethyleneglycol dimethacrylate and polyethylene
glycol 400 dimethacrylate. For the first composite system, magnetic nanoparticles were
incorporated into a hydrogel matrix by mixing them with the monomer solutions prior to
polymerization. Additionally, core-shell composites were prepared through surface
initiated polymerization of hydrogels on core magnetic nanoparticles. The various
composite hydrogel systems were characterized for their swelling response to
environmental temperature. Also, the response of these composites to the application of an
external oscillating magnetic field and the resultant heating was characterized as a function
of the amount of particles present in the composite.
A6 – Keynote Paper
ENGINEERED NANOPARTICULATE SYSTEMS FOR BIOMEDICAL
APPLICATIONS
Brij Moudgil, P. Sharma, S. Brown, V. Krishna, D. Dutta and S. Santra*,
Department of Materials Science & Engineering, and Particle Engineering
Research Center, University of Florida, Gainesville, Florida 32611, USA;
bmoudgil@erc.ufl.edu; *University of Central Florida, Orlando, Florida, USA
236
The development of innovative nanoparticulate-based systems for next-generation
processes and devices requires cross-disciplinary expertise. Through cross-disciplinary
collaborations, advances have been made in manipulating particulate-based systems at the
molecular/nanoscale for enhanced performance in biomedical applications. Novel
techniques for nanoparticle synthesis and surface modification have led to progress in
enhanced drug delivery, drug detoxification, and multi-faceted bio imaging. In this
presentation, highlights of significant advances made in targeted areas such as photostable
nanoparticle-based imaging systems, pulmonary therapeutics, nanoparticle toxicity,
engineered nanocomposites for biohazard reduction, and microemulsion technology in
detoxification of drugs in the human body will be discussed.
187
Oral Abstracts
K2 – Keynote Paper
FACTORS TO CONSIDER IN DEVELOPING A DRY POWDER INHALER
David L. Gardner and Robert A. Casper, Respirics Inc.-6008 Triangle Dr.
Suite 101 Raleigh, NC 27617, USA; dgardner@respirics.com
237
Although metered dose inhalers (MDIs) are the mainstay of delivering drugs topically to
the lungs for the treatment of asthma and COPD, DPIs are being actively pursued because
of two primary factors, i.e., the ban imposed upon CFC-based MDI products and the
emergence of GSK’s Advair Diskus® DPI combination product for the treatment of asthma
and COPD. Although several CFC-based MDIs have been reformulated into HFA-MDIs,
DPIs have certain attributes that make them a viable alternative to the MDI, i.e., the
elimination of environmental concerns related to CFC- or HFA-based products and the
common coordination issue associated with MDI use. One issue with the current marketed
DPIs is their dose variability due to the inspiratory flow rate achieved by the patient and the
flow resistance within the DPI. This dose variability implies that different amounts of the
drug are reaching the respiratory tract, dependent upon the patient’s inspiratory effort.
Thus, this variability will result in sub-optimal management and control of the patient’s
disease. Respirics, Inc. is developing DPIs (trademarked Acu-Breathe™) that are designed
to deliver medications to the respiratory tract, either on an acute or chronic basis, and
which we believe will reduce dose variability. The dose variability issue is addressed
through the I-point™ technology incorporated in the DPIs, i.e., a dose is released to the
patient only after a predetermined inspiratory flow rate has been achieved by the patient.
This paper will provide (1) a brief overview of the inhalation technologies available and
some of the issues surrounding their use; (2) discuss the principle factors to consider in the
development of a DPI product; and, (3) to present in vitro data of model drugs relating to
dose delivery and respirable mass in support of the Acu-Breathe™ technology.
K2 – Invited Paper
PARTICLE FABRICATION FOR AEROSOL DRUG DELIVERY
Andrew R. Martin, and Warren H. Finlay, Department of Mechanical
Engineering, University of Alberta, Edmonton, AB, Canada, T6G 2G8;
Warren.Finlay@ualberta.ca; armartin@ualberta.ca
238
The site within the respiratory tract at which an inhaled aerosol particle will deposit is
strongly influenced by the particle’s size and shape. For topical treatment of certain lung
diseases, it is preferable to target deposition in the tracheo-bronchial airways, while for
systemic delivery to the blood stream, deposition in the alveolar region is required.
Delivery of therapeutic agents to non-targeted sites not only reduces the efficiency of
treatment, but can lead to undesirable side effects. Current delivery systems are able to
target specific regions of the lungs in a broad sense, primarily by tailoring aerodynamic
particle sizes to encourage deposition in targeted areas. Particle size and shape also
influence translocation of deposited particles by pulmonary clearance mechanisms. For
example, industrial hygienists and toxicologists are familiar with the ability of inhaled
nanopartilces to avoid mucociliary clearance, and of long, thin fibers to hinder clearance by
188
Oral Abstracts
alveolar macrophages. In the context of drug delivery, such characteristics might be
benificial in reducing clearance of particles away from targeted regions. Presently, we are
exploring methods of delivering aerosols of unconventional size and shape to the lungs.
These include delivery of nanoparticles as micron-sized clusters, as well as generation of
fibrous aerosols from porous thin films. In the latter case, separation of columnar thin film
microstructures from their substrate has yielded discrete particles. In the long term, we
anticipate that the influence of particle size and shape on physical mechanisms involved in
deposition and clearance of inhaled particles will play an important role in the development
of next-generation respiratory drug delivery systems.
K2 – Invited Paper
PARTICLE AGGREGATION IN THERAPEUTIC AEROSOLS
Philippe G. Rogueda, AstraZeneca R&D Charnwood, Bakewell Road,
Loughborough, LE11 2HD, UK; philippe.rogueda@astrazeneca.com
239
The aim of this work was to test the theories of aggregation in aerosol droplets developed
by Igor Gonda in the mid 80’s. In order to explain high dose limitations in suspension
pMDIs (pressure metered dose inhalers), it has been suggested that solid drug particles
form large aggregates in aerosol droplets. Gonda’s theory was developped to explain the
aggregation, but has never been tested in pMDI HFA (Hydro fluoro alkanes) aerosols.
Experiments were carried out on 2 model systems: micronised lactose (Dv50 = 1.4 μm) and
a micronised inhalation drug (3-[2-(4-hydroxy-2-oxo-3H-1,3-benzothiazol-7-yl )
ethylamino]-N-[2-[2-(4-methylphenyl) ethoxy) ethyl] propansulphonamide, Dv50 = 1.5
μm). The drugs were suspended in HFA 227, with and without Triton X100 (TX100) as a
stabiliser. 50 μl Valois valves were used. 20 suspensions of varying solid drug content
were prepared for each system, concentrations ranged from 0.1 % to 10 %w/w. Aerosol
sizing measurements were performed with the Malvern Spraytec (light scattering
measurements yielding geometric diameter volume size distribution) and the TSI APS
(time of flight measurements yielding aerodynamic diameter number size distribution).
Droplet sizes measured by both techniques did not evidence the size increase predicted by
the theory. It is suggested that this theory may not apply to HFA pMDI systems. As a
consequence dosing limitation at high solid contents in pMDI may not be due to the
formation of large aggregates.
K2 – Invited Paper
AN OVERVIEW OF ALKERMES AIR® DRY POWDER PARTICLE
FORMULATION TECHNOLOGY FOR PULMONARY DELIVERY
Michael M. Lipp, Alkermes Inc., 88 Sidney St., Cambridge, MA 02139, USA;
mike.lipp@alkermes.com
240
Particle design and engineering has enabled several advances in the area of dry powder
formulations for pulmonary drug delivery. Modern methods for creating aerosol particles
include spray-drying, supercritical fluid-based methods and additional sophisticated liquid
droplet production technologies. Porous particles for inhalation produced via the
189
Oral Abstracts
Alkermes AIR® technology are characterized by geometric diameters > 5 microns and low
densities (< 0.4 g/cc), yielding aerodynamic diameters of approximately 1-5 microns for
optimal lung deposition (Edwards et al., 1997; Dunbar et al., 2002). Increasing the
geometric diameter increases the dispersibility of the powder, making it possible to
efficiently deliver a wide range of doses using a simple, passive DPI. An overview is
provided of the Alkermes AIR® technology with a focus on the impact of particle
engineering on the resultant preferred properties of the particles.
K2 – Invited Paper
ELECTROSTATIC MEASUREMENT METHODS IN
PHARMACEUTICAL AEROSOLS
Matti Murtomaa, Laboratory of Industrial Physics, Department of Physics,
FI-20014 University of Turku, Finland; matti.murtomaa@utu.fi
241
The electrostatic charge carried by respirable particles has many effects on the function of
a dry powder inhaler (DPI) and on the lung deposition. Used powders, both carries and
active drugs, tend to be electrically insulating by nature, and therefore they will inevitably
charge during the operation. The charge transfer process is very complicated due to the fact
that the powder is usually a mixture consisting of two materials which differ considerably
in particle size. The particles will acquire charge when the DPI is moved, the dose is
measured, the dose is released, and when the drug and carrier particles separate. The key
factors in the charging process are the materials, moisture and the nature of the contact.
Unfortunately, the frictional charging (or tribo-charging) is a phenomenon which is not
thoroughly understood and predictions about the magnitude or the even polarity of the
charge are hard to make. Since the importance of the electrostatics in the pharmaceutical
aerosols is widely accepted, laboratory measurements are needed to assess the phenomena.
In this presentation, different measurement methods are presented. It is shown that by
using various complementary methods, a comprehensive picture of the situation can be
formed. For example, a simple net charge measurement can give information about the
effect of device materials or particle morphology, when a time-resolved measurement
gives information about the separation of the drug and carrier particles. The presentation
focuses on the devices which have been designed and built at the University of Turku,
Finland, but other measurement methods will also be covered. Examples of the results
which have been obtained with the devices will be presented.
K2 – Invited Paper
POWDER SURFACE IMAGE ANALYSIS IN SCREENING OF
FUNCTIONAL BULK PROPERTIES OF PHARMACEUTICAL
PARTICLES
Niklas Sandler, Solid State Group, School of Pharmacy, University of Otago,
Dunedin New Zealand and Osmo Antikainen, Division of Pharmaceutical
Technology, University of Helsinki, Finland;
niklas.sandler@stonebow.otago.ac.nz
242
It is necessary to obtain particle size data of materials in various phases of the drug
190
Oral Abstracts
development process including the preformulation stage of new chemical entities (NCE)
and later stage drug product manufacturing. For instance, the particle size of a NCE has to
be evaluated with respect to whether it has a significant effect on dissolution rates,
bioavailability, stability, prosessability, or drug product content uniformity. Furthermore,
the bulk properties and behaviour of a material in different unit operations used in drug
manufacturing depend to a great extent on its particle size distribution. Various techniques
for measuring the particle size distribution of powders exist and the choice of method has
to be made carefully based on material characteristics and type information required.
Common methods used with conventional pharmaceutical powders are sieving, laser
diffraction and image analysis (IA). Recently, a new IA concept of characterizing physical
material properties by examining texture features of monochromatic images of
pharmaceutical powder surfaces instead of properties of single particles has been
introduced. In controlled illumination conditions the particle size of a material can be
determined fast and reliably from digital images of undispersed powder surfaces. The
technique has been successfully used in at-line particle size monitoring during wet
granulation and in granule growth kinetics research. By using different surface imaging
setups screening of functional properties of bulk powders and granules can be possible.
The purpose of this presentation is to demonstrate the use of the surface image analysis
approach in particle size monitoring during fluidized bed granulation, in prediction further
prosessability using multivariate visualisation and to show the potential of the technique in
evaluation of particle size related segregation behaviour during tablet manufacture.
K2 – Contributed Paper
A NOVEL POROUS HOLLOW SILICA NANOPARTICLES FOR
DRUG/PESTICIDE RELEASE CONTROL
Li-Xiong Wen, Fan Liu, Zhu-Zhu Li, Jian-Feng Chen, Key Lab for
Nanomaterials, Ministry of Education;Research Center of the Ministry of
Education for High Gravity Engineering and Technology, Beijing University
of Chemical Technology, Beijing 100029, PR China; and Jimmy Yun,
NanoMaterials Technology Pte Ltd., Blk26 Ayer Rajah Cresent 07-02,
Singapore 139944; chenjf@mail.buct.edu.cn
243
Carrier materials play a key role in the controlled drug delivery applications. However,
conventional carriers have various limits such as low loading capacity, synthesis
complexity, high cost, environment maleficent, etc. Novel porous hollow silica
nanoparticles (PHSNs) were, therefore, developed by our group through a novel sol-gel
route using inexpensive inorganic nano-templates. These new environment-friendly
materials had a core-shell structure with nearly uniform meso-pores and a high surface
area. The simple synthesizing method enabled successful and readily repeatable
preparation of PHSNs in both flask and pilot reactors without any significant negative
scaling-up effect. The as-synthesized PHSNs were applied to encapsulate different
water-soluble or oil-soluble drugs/pesticides, including brilliant blue F (BB), bentazone,
ibuprofen, avermectin and validamycin, through either a simple immersing method or a
supercritical fluid loading method. The active substances could all be loaded efficiently on
PHSNs, with a loading capacity as high as 1.67:1 (avermectin:PHSNs) by weight. All of
191
Oral Abstracts
the entrapped active substances demonstrated a typical sustained release pattern from the
carriers when immersed in some release medium and the PHSNs also showed a remarkable
UV shielding ability for the entrapped active drugs. The drug release rate could be
controlled by adjusting the pore size and shell thickness of PHSNs, and it was also
influenced by the pH and temperature of the release medium. Using the avermectin-loaded
PHSNs, an avermectin controlled release formulation was prepared and the biological tests
on its killing effects were conducted. It was found that the new formulation could kill pest
more efficiently and last for longer than conventional formulations, with lower toxicity and
cost. It therefore illustrated that the novel PHSNs can be utilized as a promising carrier for
the controlled drug/pesticide release for industrial applications.
K2 – Invited Paper
Hans Leuenberger, President of the Swiss Society of Pharmaceutical
Scientists, Institute of Pharmaceutical Technology, Pharmacenter,
Klingelbergstrasse 50, 4056 Basel, Switzerland; hans.leuenberger@unibas.ch
244
FDA‘s PAT (Process Analytical Technology) Initiative is a revolutionary paradigm change
concerning the “Pharmaceutical cGMPs for the 21st century”. The actual performance of
the pharmaceutical industry is ca. Two Sigma, i.e. ca. 4.5% defectives. The defectives are
eliminated by a final and costly “testing-in the quality”. The champion is the chip industry
with Six Sigma, i.e. with only 2ppb defectives. The new FDA requirements focus on
“Design of Quality” and not to “test -in“ the quality. Ca. 80% of the pharmaceutical
products on the market are solid dosage forms, which are developed based on
pharmaceutical powder particle technology. Thus, the development of a rigorous scientific
framework in this area is of highest priority. The paper addresses typical problems of
critical processes and formulations and proposes a “Road Map” to achieve as fast as
possible the top of the “Knowledge Pyramid” often cited by FDA. The road map proposes
the extensive use of a multivariate design of experiments including artificial neural
networks (ANN), and the use of percolation theory for a better understanding of complex
systems. An important question is whether it is possible to “translate” the existing laws of
physical chemistry into the area of powder particle technology, where we have the problem
that the number of particles involved is much lower than the Avogadro number NA. For this
purpose, the results of Nanoscience should be integrated, especially in the area of
mathematical modeling of the fascinating special physical properties of nanoparticles,
which again consist of a finite number N of “particles” in this case atoms, respectively
molecules, with N << NA.
H2 – Invited Paper
LIPOSOMAL FORMULATION OF A PHOTOSENSITIZER: GREEN
LIGHT FOR AN OLD SUBSTANCE
Alfred Fahr, L. Restetzki, FSU Jena, Institute of Pharmacy, FSU Jena,
Lessingstrasse 8, D-07743 Jena, Germany; D. Scheglmann and V. Albrecht,
Biolitec AG, Winzerlaer Strasse, D-??, Jena, Germany;
alfred.fahr@uni-jena.de
245
192
Oral Abstracts
Photodynamic therapy (PDT) is a promising new technique being explored for use in a
variety of medical applications and is known as a well-recognized treatment for the
destruction of tumors. Another possible application of PDT is the treatment of infectious
diseases due to pathogenic micro organisms. The use of PDT for the treatment of various
types of disease has been limited due to the inherent features of photosensitizers (PS).
These have included their high cost, extended retention in the host organism, substantial
skin photo toxicity, low solubility in physiological solutions (which also reduces its
usefulness for intravascular administration as it can provoke thromboembolic accidents),
and low targeting effectiveness. These disadvantages, had led to the administration of very
high doses of a photosensitizer, which dramatically increase the possibility of
accumulation of the photosensitizer in non-damaged tissues and the accompanying risk of
affecting non-damaged sites. The usual formulation of these photosensitizers consists of an
ethanolic solution, which causes the solubilized drug after i.v. injection to precipitate at the
injection site. This induced very slow pharmacokinetics, more resembling an oral PK
profile. Solubilization of the drug by liposomes changes this PK profile dramatically. It
looks now like a typical i.v. profile, the drug does not stay for a long time in the blood
circulation, but despite of the rapid elimination from blood the photosensitizer penetrates
to a larger extent than the ethanolic formulation into tumour tissue, presumably as host
inside the liposomal membrane. This is maybe due to the enhanced permeability and
retention effect. As the drug sits because of its hydrophobicity in the liposomal bilayer, it is
able to diffuse out of the membrane to e.g. surrounding tumour cells at longer times and
may increase by this its pharmacodynamic activity in tumour tissue. The patient benefits
from this rather physical formulation approach also by a reduced topical phototoxicity
because of the rapid clearance from blood.
H2 – Invited Paper
USE OF A SCATTERING ELEMENT AND DIRECT DE-IONIZED
WATER-COOLING IN HIGH POWER SEMICONDUCTOR DIODE
LASERS TO ENHANCE THE BEAM DIVERGENCE AND
PERFORMANCE FOR USE IN PHOTODYNAMIC THERAPY (PDT)
Amaranath Premasiri, Gemunu Happawana, Mechanical Engineering
Department, Southern Methodist University, Dallas, TX; Gary Evans,
Electrical Engineering Department, Southern Methodist University, Dallas,
TX; and Arye Rosen, Electrical and Biomedical Engineering Department,
Drexel University, Philadelphia, PA; happawan@engr.smu.edu
246
Use of high power semiconductor diode lasers in a light delivery system to be used in
photodynamic therapy (PDT) of cancer treatment makes the system portable and
inexpensive. Semiconductor diode lasers convert electrical power to optical power with
higher efficiency than any other device, yet there are two main disadvantages associated
with semiconductor laser when it is used in such systems. One is high temperature within
the laser which contributes to device degradation and wavelength shifts, and the other is the
low beam divergence that does not give uniform illumination in all directions. These two
drawbacks can be largely overcome by introducing direct de-ionized water cooling and by
193
Oral Abstracts
using a polymer coating with embedded scatters on the laser facets in order to uniformly
disperse the laser light. Edge emitting semiconductor lasers emitting at a wavelength of
635 nm were immersed in de-ionized water, resulting in significant increases in output
power and wavelength stability. Different types of scattering elements were used with a
transparent polymer matrix. The optimum volume, shape and size of scattering elements in
the matrix material to provide uniformly distributed light was calculated using Mie theory.
The optimal polymer thickness was determined by finding the dependence of the
uniformity of the radiation pattern on the length of the scattering element. The theory and
experimental results show that TiO2 is the best material for this application. This study has
shown that introducing scattering elements and de-ionized water cooling improve the
performance of semiconductor diode laser in light delivery systems for PDT.
H2 – Contributed Paper
DEVELOPING MULTIFUNCTIONAL NANO-ARCHITECTURES:
LUMINESCENT AND SUPERPARAMAGNETIC
Benoit Simard and Dongling Ma, National Research Council of Canada,
Steacie Institute for Molecular Sciences, 100 Sussex Drive, Ottawa, ON K1A
0R6, Canada; Benoit.Simard@nrc-cnrc.gc.ca; Dongling.Ma@nrc-cnrc.gc.ca
247
This work aims at combining three useful functionalities: superparamagnetism,
luminescence and readily functionalizeable suface into one multifunctional
nano-architecure. The strategy we used is designing a nanostructure containing a
superparamagnetic core and a luminescent silica shell, which encapsulates thousands of
dye molecules. Traditional Stöber and reverse microemulsion methods have been tried
seperately and the results are not satisfactory. Agglomerations, many core-free silica
nanoparticles and irregular over-microscale hybrid networks were observed. To achieve
the desired nanostructure with better control, we have developed a new two-step approach.
In the first step, the first silica shell with specific thickness is coated onto iron oxide
nanoparticles through a modified Stöber method. Next, the dye is doped into a second
silica shell through a reverse microemulsion method. The synthesis yields core-shell
nanoaprticles with improved morphology over the above two methods used independently.
The key factor leading to the success in synthesizing this delicate nano-architecture resides
in the use of “disguised” silica nanoparticles in the reverse microemulsion for the dye
doping process. The “disguised” silica nanoparticles actually contain magnetic cores, but
the core-core dipolar interactions are shielded by the first silica shell. Therefore, the same
or slightly modified reverse microemulsion conditions should be applicable to various
magnetic nanoparticles for dye doping as long as they are already covered by a silica shell
thick enough to isolate their magnetic interactions. We consider this new approach as an
important step towards developing a universal and simple synthesis for silica based,
multifunctional core-shell nanostructures. We have worked on several dyes using this
approach such as tris(2,2’-bipyridine) ruthenium (II) chloride and
fluorescein-5-isothiocyanate. The novel hybrid nanomaterials demonstrate marked
advantages over the uncoated materials, including enhanced collodial stability, increased
luminescence density and reduced magnetic blocking temperatures. Herein, we report their
synthesis, magnetic and photophysical properties as well as their applications.
194
Oral Abstracts
H2 – Invited Paper
CANCER NANOTECHNOLOGY: DESIGNING MULTIFUNCTIONAL
NANOSTRUCTURES FOR TARGETING TUMOR CELLS AND
VASCULATURES
Shuming Nie, Gloria J. Kim, Departments of Biomedical Engineering,
Chemistry, Materials Science and Engineering, Hematology and Oncology,
101 Woodruff Circle, Suite 2001, Atlanta, GA 30322, Fax: 404-727-3567,
snie@emory.edu
248
Significant progress has been made in developing new agents against cancer and in
formulating them for in-vivo delivery and targeting. Research in genomics and proteomics
continues to uncover biomolecular signatures (biomarkers) that are unique to cancer
development and progression. Yet, the major challenge to target and selectively kill cancer
cells remains. Linked with targeting moieties such as tumor-specific ligands or monoclonal
antibodies, nanoparticles can be used to target tumor cells and tumor vasculatures. We
have attained dramatic in vivo tumor shrinkage and tumor vasculature disruption using
ternary biomolecular nanostructures. For hydrophobic anti-cancer agents not amenable to
chemical conjugation, we have used the principles of molecular self-assembly to engineer
targeted nanoparticles. These nanoparticles are also applicable to delivery and targeting of
diagnostic and imaging agents. In particular, bioconjugated quantum dots make it possible
to track movement of individual labeled molecules inside a cell or a small number of
cancer cells growing in a living animal. Multifunctional nanostructures that can serve as
phototherapeutic agents to selectively diagnose and treat cancer are currently under
development. The ability to design multifunctional nanostructures has opened new
opportunities in early cancer diagnostics, molecular profiling, and integration of cancer
therapy and imaging.
H2 – Contributed Oral
La0.75Sr0.25MnO3-BASED MAGNETIC NANOPARTICLES AS POTENTIAL
HEAT MEDIATORS IN ONCOLOGY
Sebastien Vasseur, Etienne Duguet, Institute of Condensed Matter Chemistry of
Bordeaux (ICMCB), University of Bordeaux, 87 ave Dr Schweitzer, 33608 Pessac
Cedex, France; Eva Hadova, Emil Pollert, Institute of Physics (FZU), Academy of
Sciences of the Czech Republic, Cukrovarnicka 10, 16253 Praha 6, Czech Republic;
vasseur@icmcb-bordeaux.cnrs.fr
249
Hyperthermia consists in heating a cancerous tissue either to destroy directly tumour cells by
necrosis or to improve drug or radiation efficiency. One promising route uses alternative
magnetic fields allowing to magnetic materials to absorb electromagnetic energy and convert it
into heat. In particular, magnetic fluid hyperthermia takes advantage of magnetic nanoparticles
dispersion which could be administered by intravenous injection. Among the numerous
requirements, two are of great importance : (i) the temperature must be controlled in vivo in order
to avoid safe tissue overheating and (ii) the nanoparticles must be surface-derivatized not only for
ensuring their stealthiness in the blood compartment towards macrophages (e.g. pegylation) but
195
Oral Abstracts
also for being labelled with appropriate targeting ligands. Our strategy is to take advantage of the
temperature-dependence of the magnetic properties of manganese perovskites La1-xSrxMnO3,
whose Curie temperature may be tuned from –130 to 100°C by varying substitution value x. So,
as soon as medium temperature reaches Curie temperature, particles lose their magnetic
properties and therefore their heating ability. Such particles would be both heaters and fusers.
La0.75Sr0.25MnO3 nanoparticles were synthesized by citrate route, followed by annealing and
milling. Optimal annealing conditions were determined as a compromise between high
crystallinity, high magnetic properties and low size. In these conditions, 60-nm particles were
synthesized. Under a 108 kHz / 88 mT alternative magnetic field, they exhibited specific heating
power of 40 W/gMn and reached a maximal heating temperature of about 46°C, making such
particles suitable for safe hyperthermia applications. Silica encapsulation of La0,75Sr0,25MnO3
particles led to core-shell particles with reduced cytotoxicity and opened the way to their surface
functionalization.
H2 – Invited Paper
PHOTOSENSITISER-MACROMOLECULE CONJUGATES FOR
TARGETED PHOTODYNAMIC THERAPY
Ross W. Boyle, Nela Malatesti, Robert Hudson, Karen Smith and John
Greenman, Department of Chemistry & Clinical Biosciences Institute,
University of Hull, Kingston-upon-Hull, East Yorkshire, HU6 7RX, UK;
r.w.boyle@hull.ac.uk
250
Photodynamic Therapy (PDT) is a treatment for the eradication of unwanted or
inappropriate tissue, including solid tumours and neaovasculature. PDT relies on the
combination of a photosensitising drug, high intensity light in the visible or near infrared
regions and molecular oxygen. The therapeutic effect is dependent on all three factors
being optimised. Laser based PDT light sources and fibre optics now allow precise
delivery of high intensity light to the treatment area, and little can be done to influence
levels of tissue oxygenation, thus the major opportunity for further optimisation of PDT is
by more accurate targeting of photosensitisers. Conjugation of PDT sensitisers to
macromolecules, both biological and synthetic, has the ability to alter biodistribution and
pharmacokinetic parameters, thus improving targeting and enhancing the therapeutic
effect. Synthetic strategies for conjugation of porphyrin based photosensitisers to
macromolecules, including antibodies, will be presented and properties of the resulting
conjugates, including target cell binding, internalisation, intracellular distribution, and
mechanism of photocytotoxicity, will be discussed.
H2 – Contributed Paper
INDOCYANINE GREEN-LOADED NANOPARTICULATE DELIVERY
SYSTEM FOR SUPERFICIAL TUMOR DIAGNOSIS AND TREATMENT
Jun Shao, Vishal Saxena, Mostafa Sadoqi, St. John’s University, 8000 Utopia
Parkway, Jamaica, NY 11439, USA; shaoj@stjohns.edu
251
The objective of this project was to develop an intravenously administrable
196
Oral Abstracts
poly(dl-lactic-co-glycolic acid) (PLGA) nanoparticulate delivery system for Indocyanine
Green (ICG), to enhance the potential for ICG use in tumor imaging and therapy. For this
purpose PLGA nanoparticles entrapping ICG were engineered by spontaneous
emulsification solvent diffusion method. ICG entrapment in nanoparticles was determined
and physicochemical characterization of nanoparticles was performed. The stability of
ICG in nanoparticles formulation under various conditions was determined. The
intracellular uptake of ICG in nanoparticles by B16-F10 and C-33A cancer cell lines was
studied in comparison with the free ICG solution. Anti-proliferation studies against cancer
cells were performed to prove the photodynamic activity of ICG in nanoparticles.
Biodistribution of ICG when delivered through nanoparticles and solution were evaluated
in mice after tail vein injection. PLGA nanoparticles with a mean diameter of 350 nm and
0.2% ICG loading were obtained. The nanoparticles were nearly spherical in shape with
negative zeta potential. The nanoparticle formulation significantly enhanced the overall
stability to ICG in water with degradation half-lives of 3-5 days at various conditions as
compared to 10-20 hr of free ICG solutions. The intracellular uptake of ICG through
nanoparticles was directly proportional to time and extracellular nanoparticle
concentration. The nanoparticles formulation enhanced about 100-fold intracellular uptake
of ICG as compared to the free ICG solution. Nanoparticle formulation showed significant
photodynamic effect at nano-molar ICG concentrations and very low light dose against the
cancer cells in vitro. Biodistribution study on mice showed that the nanoparticle
formulation enhanced the blood circulation time and retention time of ICG in various
organs 2-5 times as compared to the free solution. A stable PLGA nanoparticlute delivery
system was developed for ICG, which demonstrated the capability to enhance the potential
for ICG use in tumor diagnosis and anticancer therapy.
D6 – Keynote Paper
MAGNETIC BIOSENSORS IN BIODIAGNOSTICS
J. Manuel Perez, Nanoscience Technology Center, Department of Chemistry
and Biomolecular Science Center, University of Central Florida, 12424
Research Parkway, Suite 400, Orlando, Fl 32826, USA; jmperez@mail.ucf.edu
252
Designing activatable nanoagents to sense molecular markers, molecular interactions and
pathogens associated with disease could result in the development of more sensitive
molecular diagnostic agents. Toward this goal, we have developed an assay to sense
molecular targets using magnetic nanosensors and nuclear magnetic resonance (NMR).
These magnetic nanosensors consists of biocompatible iron oxide based magnetic
nanoparticles capable of detecting a molecular target by changes in the NMR signal of the
solution as the nanoparticles self-assemble in the presence of the target. We have shown
that these magnetic nanosensors can detect various molecular interactions (DNA-DNA,
protein-protein, protein-small molecule, and enzymatic reactions) in solution with high
sensitivity and selectivity using NMR. The assay does not require purification of the
samples and the observed target-induced change in NMR signal is detectable in turbid
media or whole-cell lysate. We will present data showing the use of this technique to detect
molecular targets involved in cancer, and viruses and toxins in solution. Furthermore,
recent advances toward improving the detection limit, speed of detection and portability of
the magnetic assay will be discussed.
197
Oral Abstracts
D6 – Invited Paper
MULTIFUNCTIONAL QUANTUM DOTS FOR MOLECULAR IMAGING
AND THERAPEUTICS
Xiaohu Gao, University of Washington, Department of Bioengineering,
Seattle, WA 98195, USA; xgao@u.washington.edu
253
The development of high-sensitivity and high-specificity probes beyond the intrinsic
limitations of organic dyes and fluorescent proteins is of considerable interest to many
areas of research, ranging from in vitro ultrasensitive detection to in vivo medical imaging.
Recent advances have shown that nanometer-sized semiconductor quantum dots (QDs) can
be covalently linked with biorecognition molecules such as peptides, antibodies, nucleic
acids, and small-molecule inhibitors for use as fluorescent probes. In comparison with
organic fluorophores, QDs exhibit unique optical and electronic properties such as sizeand composition-tunable fluorescence emission, large absorption coefficient, and
significantly improved brightness and photostability. Due to their broad excitation profiles
and narrow/symmetric emission spectra, high-quality QDs are also well suited for optical
multiplexing, in which multiple colors and intensities are combined to encode thousands of
genes, proteins, and small-molecule libraries. In this context, I present recent
developments in bioconjugated QD probes and their applications in ultrasensitive
molecular, cellular imaging and drug delivery. Despite their relatively large sizes (2-6 nm
in diameter), bioconjugated QD probes behave like fluorescent proteins, and do not suffer
from serious kinetics or steric-hindrance problems. In this “mesoscopic” size range, QDs
and other types of nanoparticles also have more surface areas and functionalities that can
be used for linking to multiple diagnostic (e.g., radioisotopic or magnetic) and therapeutic
(e.g., anticancer) agents. These recent developments toward nanomedicine are expected to
open new opportunities in molecular imaging, multiplexed profiling, disease diagnosis and
treatment.
D6 – Contributed Paper
PLASMON-ENHANCED FLUORESCENCE OF DYES ATTACHED TO
POLYELECTROLYTE COATED METAL NANOPARTICLES.
Robert Nooney, Ondra Stranik, Colette McDonagh, Brian D. MacCraith.
National Centre for Sensor Research, Dublin City University, Glasnevin,
Dublin 9, Ireland; rno@physics.dcu.ie; Brian.MacCraith@dcu.ie
254
We report on the enhancement of fluorescence that can result from the proximity of
fluorescent dyes to metal nanoparticles (NPs). This plasmonic enhancement which is a
result of the localised surface plasmon resonance (LSPR) at the metal surface, can be
exploited in order to improve the efficiency of optical biochips and thereby lower the limit
of detection. The fluorescence enhancement, which depends on the dye-NP separation was
measured and the optimum thickness of the polyelectrolyte shell determined. A model
system was chosen, consisting of NPs surrounded by a polyelectrolyte spacer shell, to
which was attached a layer of dye molecules where the LSPR wavelength was tailored to
coincide with the absorption band of the dye. Colloidal silver and silver / gold alloy
198
Oral Abstracts
nanoparticles with monodispersed spherical or triangular shapes and predetermined LSPR
absorption bands were prepared using both wet chemistry and photoconversion techniques.
The nanoparticles were coated with a polyelectrolyte shell using a layer by layer technique
and the thickness of the coating was measured using transmission electron microscopy and
UV absorption spectroscopy. Inorganic and organic dyes of different lifetimes and
quantum efficiencies were attached either ionically or covalently to the polyelectrolyte
shell. The enhancement was calculated by measuring the fluorescence of the NPs using a
microplate reader and comparing to that of the pure dye. The LSPR contribution to the
enhancement was validated by removing the metallic core using potassium cyanide and
measuring the fluorescence of the remaining polyelectrolyte vesicle. The nanoparticle /
polyelectrolyte layers were then deposited on a plastic substrate using a layer-by-layer
approach with layer number matching the optimum value determined from the colloidal
system above. Again a range of dyes were attached and the enhancement was determined.
Ultimately, this plasmon enhancement system will be used as the basis of an enhanced
bioassay platform.
D6 – Contributed Paper
NANO-BIOSENSOR FOR DETECTION AND TREATMENT OF DISEASE
Tao Liu, Hong Zhao, No.2 Bei Yi Jie, Zhong Guan Cun, Beijing,; and Long
Jiang, Key laboratory of Colloid and Interface, Center of Molecular Sciences,
Institute of Chemistry, Chinese Academy of Sciences; China;
taoliu@iccas.ac.cn, leotao1974@yahoo.com
255
Investigation indicates that the appearance of the malignant tumor is highly correlative
with the DNA mutation. It has become an important topic of the cancer study to detect the
gene mutation and look for the relation between mutation and pathological change at the
molecular level. Rapid detection for trace gene mutation can provide basic data for
diagnose disease. Therefore, looking for a rapid and simple method used for detecting trace
mutation is important and pressing. QCM is a simple, rapid and real-time measurement of
DNA binding and hybridization at the sub-nanogram level. The nanogold particle has
many special properties, for example high density, simple operation, and easy
size-controlled. Combining these two techniques, i. e., nanoparticle modification of QCM
surface and the application of gold narnoparticle amplifier, we improved the detection limit
of DNA. This method makes it possible to detect single base mutation less than 10-16 mol /
L.
D6 – Contributed Paper
BIOFUNCTIONALIZATION OF WATER-DISPERSIBLE GOLD
NANOPARTICLES
Hilde Jans1,2, Kristien Bonroy1, Filip Frederix1, Karolien Jans1,2, Bieke Van de
Broek1,2, Gustaaf Borghs1, Guido Maes2; 1IMEC, MCP-ART, Belgium;
2
K.U.Leuven, Department of Chemistry, Belgium, hilde.jans@imec.be
256
In recent years, gold nanoparticles have become the subject of intensive research for the
199
Oral Abstracts
detection and labeling of biomolecules. Due to their Localized Surface Plasmon Resonance
properties, their UV-Vis absorption spectrum is extremely sensitive to changes in the
nanoparticle size, the shape and the external dielectric environment in close proximity of
the nanoparticles. This property has led to the development of novel classes of nanoscaled
affinity biosensors. The aim of this work is to synthesize stable water-dispersible gold
nanoparticles with different sizes that can be used for the development of biorecognition
assays. The nanoparticles are functionalized with different mixed Self-Assembled
Monolayers of thiols (SAMs). This enables to realize nanoparticles with enhanced
stability. In a next step, biomolecules are immobilzed on top of these SAMs using covalent
coupling procedures. The applied synthesis route consists of a very easy “one-step in-situ
synthesis method”, which allows to realize well-defined gold nanoparticles functionalized
with two different kinds of thiols: HS-(CH2)11-PEO6-COOH and HS-(CH2)11-PEO3-OH. In
this approach the thiol molecules are mixed with the gold salt and subsequently reduced
with NaBH4. By changing the ratio of the reagents, the size of the nanoparticles can be
controlled. Next, anti-PSA antibodies are covalently coupled to the carboxylic groups of
the SAMs onto the nanoparticles. The poly-ethylene oxide moieties prevent the
non-specific binding and increase the water solubility. This synthesis route of gold
nanoparticles allows to increase the nanoparticle stability, the anti-PSA binding efficiency
and the activity of the immobilized anti-PSA antibodies. These nanoparticles can therefore
be used to create very sensitive nanoscaled affinity biosensors.
D6 – Invited Paper
A NEW PARTICLE-BASED IMMUNOASSAY THAT DEPENDS ON THE
QUANTITATIVE DETECTION OF MAGNETIC PARTICLES
Stéphane Legastelois, Guillaume Renoud : Indicia Biotechnology, 33 avenue
de la Californie, 69600 Oullins, France; slegastelois@indicia.fr ; and Luc
Lenglet, Magnisense, Tour de Rosny 2, 112 avenue du général De Gaulle,
93118 Rosny ss bois cedex, France
257
Magnetic particles are a powerful and versatile tool in biology. Bound to a suitable
antibody, they are used to label specific molecules or microorganisms. A new assay system
has been developed for the rapid and sensitive detection of proteins, virus or bacteria in
biological, environmental or food samples. This system incorporates the use of coated
superparamagnetic particles in a lateral flow or flow through format. The devices are
analyzed by a laptop reader that detects and counts the number of superparamagnetic
particles that react with the solid phase. The innovative detection technology is based on
the non-linear behavior of superparamagnetic bodies in the presence of a magnetic field.
This physical response is strictly proportional to the amount of magnetic material. Both
lateral flow membranes or flow through syringes are introduced into a coil for the magnetic
analysis. A exceptional dynamic range of six orders of magnitude is observed. In this
study, we have demonstrated that lateral flow tests can be turned into a quantitative assay,
by replacing gold colloid or latex beads by nanosized magnetic particles. The low detection
threshold enables an enhanced sensitivity of 15 to 70 fold compared to conventional lateral
flow tests. Data recording also eliminates potential subjectivity associated with
visually-interpreted tests. Another format based on a flow through device was also
200
Oral Abstracts
investigated. A cylindric solid phase built into a syringe allows the processing of large
volumes of sample, thus reducing the time of the culture phase of food or waterborne
bacteria. Assays carried out on legionella pneumophila exhibit a detection threshold of
1500 bacteria. Basically, data demonstrate that this technology is simple, accurate, and
exhibits a low limit of detection. The robustness of the method allows measurements in
almost any environmental conditions.
D6 – Invited Paper
CANCER BIOMARKR DETECTION BASED ON
PHOTOLUMINESCENCE OF SEMICONDUCTOR QUANTUM DOTS
AND SERS OF METAL NANOSTRUCTURES
Jin Z. Zhang, Adam M. Schwartzberg, Tammy Oshiro, Leo Seballos,
Abraham Wolcott, Department of Chemistry and Biochemistry, University of
California, Santa Cruz, CA 95064 USA; Chad E. Talley, Thomas R. Huser,
Department of Chemistry and Materials Science, Lawrence Livermore
National Laboratory, Livermore, CA 94550 USA; Rebecca Sutphen,
Department of Interdisciplinary Oncology, College of Medicine and H. Lee
Moffitt Cancer Center and Research Institute, University of South Florida,
Tampa, Fl, 33612 USA; and Yiping Zhao, Department of Physics and
Astronomy, University of Georgia at Athens, GA 30602, USA;
zhang@chemistry.ucsc.edu
258
Detection of cancer biomarkers at low concentration, especially for early stage cancers, is a
major challenge in cancer research, diagnosis, and treatment. Detection platforms based
on nanomaterials, including semiconductor quantum dots and metal nanostructures, offer
promising hope in developing sensitive and selective methods for cancer biomarker
detection. For example, rational design and study of new surface enhanced Raman
scattering (SERS) substrates is key to advancing chemical and biological sensing based on
SERS. The next generation of biological probes will ideally be single, small, SERS active
nanostructures able to penetrate the inner workings of cells. To this end, we have
developed various metal nanostructures based on aggregates, nanorods, and nanoshells
with the goal to optimize their SERS activities. We have very recently demonstrated
SERS from single, hollow nanostructures. Exceptional sample homogeneity leads to a
nearly tenfold increase in signal consistency over standard silver substrates. At 30 nm in
diameter, this is the smallest confirmed single SERS active particle ever reported,
representing a major step in advancing sensing technology based on SERS. In the
meantime, we have applied some of the substrates developed in the detection of cancer
biomarkers and have achieved high sensitivity and molecular selectivity. The results have
shown that SERS is extremely promising for chemical and biological sensing and imaging
applications. To control the structure of the nanomaterials and thereby their optical
absorption as well as SERS properties is critical for these emerging technological
applications.
201
Oral Abstracts
D6 – Contributed Paper
PARTICLE POPULATION CLASSIFICATION BY MICRO-FLOW
IMAGING
Dave Thomas, David King, Peter Oma, Brightwell Technologies Inc., 195
Stafford Road West, Ottawa, Ontario, Canada, K2H 9C1;
dthomas@brightwelltech.com
259
The paper will describe a new particle analysis technology which employs automated
digital image analysis to classify particulate/cell suspensions. The technology involves
drawing sample through a sheathed or unsheathed micro-fluidic cell. Sections of the
flowing fluid are illuminated with a pulsed high-intensity source, magnified and imaged
frame-by-frame on the camera’s pixel array. The system software identifies, in real time,
pixels in each frame which are wholly or partially contained within a particle image. This
information is used to isolate particles and measure particle parameters such as count,
diameter, area, perimeter, circularity, and transparency. The volume of fluid sampled in
each frame is accurately known, therefore particle concentrations are determined
absolutely. The database of images and parameter values is interrogated by the user to
produce histograms, scattergrams and to isolate sub-populations of interest. Micro-Flow
Imaging (MFI) technology will detect and classify particles ranging from 0.8 to 100
microns in size over a concentration range of 0 to 100K’s per ml. The technique is
insensitive to the particle’s optical properties and therefore offers distinct advantages over
laser diffraction and light obscuration in terms of anlyzing heterogenous populations. The
data set is intermediate between flow cytometry and manual microscopic analysis
providing the automation, statistical validity and reproducability of the former while
preserving the visual insight gained by the latter. Continuous sample introduction and
time-resolved image analysis permitting high resolution reaction monitoring and trend
charting. The paper will present experimental results applying MFI technology for general
purpose particle fabrication process control with particular emphasis upon characterization
and optimization of specific cell-related bio-processes including fermentation, viability,
purification, dissolution, preservation, and protein aggregation. Application of the
technology for detecting unwanted particulate within process fluids will also be presented,
as well as use of the technology for realtime chemical reaction monitoring.
D6 – Invited Paper
DEVELOPMENT OF COLLOIDAL SEMI-CONDUCTOR
NANOCRYSTALS AS BIO-IMAGING PROBES
Kui Yu, Steacie Institute for Molecular Sciences, National Research Council
Canada, 100 Sussex Drive; Ottawa, Ontario Canada K1A 0R6;
Kui.Yu@nrc-cnrc.gc.ca
260
Colloidal semiconductor quantum dots (QDs), which are spherical in shape with diameter
on the order of 1 – 10 nm, have attracted a lot of attention recently, due to their
size-dependent properties, for instance, CdSe nano-crystals emit from blue to red
depending on their size, and due to their promise of practical applications to substitute
202
Oral Abstracts
fluorescent dyes for bio-imaging. This presentation will address our comprehensive study
on the synthetic factors as well as the dispersing media affecting the PL properties of
quantum dots such as CdSe, in addition to our recent study on the bio-distribution of
nano-crystals inside live mice. Furthermore, post-treatments aiming at high performance
will be dealt with. The post-treatments for better surface passivation involve growing an
inorganic shell hetero-epitacitically; during the post-treatment, radiative recombination of
light-generated charge carriers increases. The insights gained from our comprehensive
study facilitate the development of imaging probes based on a deeper understanding of the
fundamental chemistry and physics of high-quality nanocrystals from large-scale
production with a high degree of synthetic reproducibility.
I3 – Keynote Paper
NANOMEDICINES FOR EFFICIENT DRUG AND GENE DELIVERY
Ijeoma F. Uchegbu, Xiaozhong Qu, Woei Ping Cheng, Andreas G.
Schätzlein1, Nanomedicines Research Centre, Department of Pharmaceutical
Sciences, University of Strathclyde, Glasgow, UK. 1Nanomedicines Research
Centre, Cancer Research UK Centre for Applied Pharmacology and Medical
Oncology, University of Glasgow, Glasgow G61 1BD;
I.F.Uchegbu@strath.ac.uk
261
Our objectives are the design and fabrication of functional nanosystems based on
amphiphilic polymers and poly(propylenimine) dendrimers, which enhance the
bioavailability of hydrophobic drugs and anti-cancer genes. Linear soluble polymers
grafted with hydrophobic and hydrophilic groups result in amphiphiles, which via
hydrophobic associations yield various nanostructures such as dense nanoparticles, bilayer
vesicles and polymeric micelles; all of which may be used for drug delivery. Water soluble
amphiphilic carbohydrates self assemble into polymeric micellar clusters which improve
aqueous levels of propofol by 2000 fold and prednisolone by 8 fold. Optimum drug/
polymer ratios in aqueous media are 48: 1 for propofol and 67: 1 for prednisolone; values
that are between 16 and 300 times higher than those shown by the Pluronic block
copolymers. Polymeric micellar clusters, when compared to commercial formulations
produce a 10 fold increase in topical ocular prednisolone levels in the rabbit model and a 10
fold increase in intravenous propofol pharmacodynamic activity in the mouse model.
Additionally, other amphiphilic polymers facilitate the oral absorption of cyclosporine,
giving similar bioavailability levels to the commercial formulation Neoral®. Low
molecular weight polypropylenimine dendrimers (MW < 1700 Da), by virtue of their high
nitrogen density are excellent DNA carriers and gene transfer agents. Interestingly,
systemic gene transfer in tumor bearing animals results in tumor gene expression which is
3 fold that produced by either Exgen-500 (linear polyethylenimine, Mw = 25,000 Da) or
naked DNA. Additionally these dendrimers are tumoristatic agents and have thus been
used to make an efficient tumor necrosis alpha gene medicine, which shows tumor ablation
in the A431 tumor mouse model and excellent tumoricidal activity in the LS174T, B16F10
and C33a mouse tumor models. These data demonstrate that polymeric and dendrimer
nanosystems may be exploited to yield efficient nanomedicines.
203
Oral Abstracts
I3 – Invited Paper
NOVEL POLYMER TECHNOLOGY FOR THE DELIVERY OF
BIOLOGICAL MACROMOLECULES
William G. Turnell, Medivas, LLC., 6275 Nancy Ridge Drive, CA 92121
USA; bturnell@medivas.com
262
Synthetic analogs of naturally occurring macromolecules (“biologics”) constitute a large
and important class of therapeutic compounds that have come to underpin a multi-billion
dollar industry, despite the majority of these products having to be administered by
injection. This presentation examines the fundamental barriers associated with delivery of
biologics, citing oral insulin and vaccine formulations as examples. Data will be presented
to show that amino acid based poly(ester amide) and poly(ester urethane) polymers help
protect peptides and whole proteins from bio-degradation, whilst preserving native
structure and bio-activity. This protective and controlled delivery of the biologic is
achieved in concert with complete bio-degradation of residual polymer. For efficient
protein-polymer coupling, both covalent, via amide or ester bond formation, and
non-covalent conjugation schemes are described. The latter is designed for His6-tagged
recombinant proteins coupled to each repeating unit of a nickel-decorated version of the
polymer. This formulation strategy forms the basis of a rapid response program for the
provision of vaccines against newly emerging pathological viral stains, such as both
seasonal and pandemic influenza.
I3 – Invited Paper
MICELLAR NANOPARTICLES
Robert W. Lee and Dinesh B. Shenoy, Novavax, Inc. 508 Lapp Road,
Malvern, PA 19355, USA; rlee@Novavax.com
263
This paper describes Novavax’s proprietary Micellar Nanoparticle drug delivery
technology. Novavax, Inc. is a biopharmaceutical product development company focused
on the research, development and commercialization of products utilizing its proprietary
drug delivery and biological technologies for large and growing markets. Micellar
Nanoparticle (MNP) technology (US Patent #5,629,021) is the basis for the only FDA
approved product, ESTRASORB®, consisting of a nano-technology-based, cosmetically
appealing lotion-like topical dosage form. MNP’s represent a composite vehicle that
presents the drug in a variety of fractions: aqueous or hydro-alcoholic solution, micellar
solubilized form, oil fraction and as surface-stabilized micro-/nano-crystals. This
formulation approach creates a microreservoir-dissolution-controlled system that is
capable of incorporating both water-soluble and water-insoluble active pharmaceutical
ingredients and delivering them either topically (skin being the target tissue) or
transdermally (systemic delivery). The physicochemical attributes of MNP’s will be
described in relationship to what makes this drug delivery technology unique.
204
Oral Abstracts
I3 – Invited Paper
TISSUE TARGETED NANOPARTICLES FOR SYSTEMIC DELIVERY OF
NUCLEIC ACID AGENTS ENABLES siRNA THERAPEUTICS
Martin Woodle, Intradigm Corporation, 12115 Parklawn Drive, Suite K,
Rockville, MD 20852, USA; mwoodle@gmail.com,
mwoodle@intradigm.com
264
RNAi, and in particular the short dsRNA oligonucleotide active intermediate called
siRNA, has revolutionized gene function research by providing an effective tool to
selectively inhibit gene expression. This capability has altered dramatically drug target
discovery and validation, but largely in cell culture. Intradigm now has developed tissue
targeted nanoparticle systems that are proving to be an effective means to utilize siRNA
oligonucleotides in vivo and via systemic administration, both as a powerful method for
drug target research and most importantly as a means to use siRNA as a therapeutic
modality. Application of a modular polymer chemistry approach has succeeded in
development of unique nanoparticles that can achieve the different functions required to
solve the long standing challenge of intracellular delivery of nucleic acid agents for
therapeutic applications. The system has been developed for use of siRNA for drug target
discovery and validation, operating directly in clinically relevant animal models, which
generates the most useful gene function information. Results will be presented showing
discovery in extremely rapid fashion a portfolio of novel cancer therapeutic targets and
validation of a few for monoclonal antibodies and other classes of therapeutics. The
presentation will also present development of a nanoparticle-siRNA system combining
tissue selective delivery with gene selective inhibition by the siRNA payload, opening the
door to dual-targeted therapeutics. Intradigm is developing a first product in this class,
ICS-283, for inhibition of neovascularization and angiogenesis in cancer, ocular diseases,
and other critical diseases. In addition, Intradigm is developing this system with
collaborators in other therapeutic areas.
I3 – Invited Paper
POLY-L-GLUTAMIC ACID AS A BUILDING BLOCK FOR
NANOMEDICINE: FROM THEAPEUTICS TO MULTIMODALITY
DIAGNOSTICS
Chun Li, Department of Experimental Diagnostic Imaging, The University of
Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Houston, TX
77030, USA; cli@di.mdacc.tmc.edu
265
Poly(L-glutamic acid) (PG) is a biodegradable polyamino acid possessing excellent
physicochemical properties as a drug carrier for both diagnostic and therapeutic agents.
PG-paclitaxel conjugate (PG-TXL) developed in our laboratatory accumulated selectively
in solid tumors due to enhanced permeability and retention effect of macromolecules, and
the conjugate demonstrated remarkable antitumor activity in preclinical studies. Owing to
prolonged release of paclitaxel from PG-TXL in the tumors, PG-TXL used in combination
with radiotherapy results in significant improvement in tumor control compared with
205
Oral Abstracts
individual treatment and in comparison with other preclinical in vivo data for combined
chemo- and radiotherapy. PG-TXL has now advanced to clinical phase III studies.
Conjugation of gadolinium p-aminobenzyl-diethylenetriaminepentaacetic acid
(Gd-DTPA) to PG resulted in a macromolecular magnetic resonance imaging (MRI)
contrast agent that could be used not only for blood-pool imaging but also for assessing the
extent of necrosis because it selectively localized to necrotic areas of tumors 2-5 days after
intravenous injection. Our data suggest that the enhanced permeability and retention effect
of PG-based polymeric chemotherapeutic agents is attributable to their selective
accumulation and retention in the necrotic areas of the tumors. To further enhance delivery
efficacy, we synthesized and characterized dendritic PG that allows attachment of multipe
targeting moieties at the termini of dendritic polymer chains. Using a near-infrared
fluorescence dye indocyanine green (ICG) as a model diagnostic agent and folic acid as a
model targeting moiety, we showed that the resulting nanometric conjugate,
PAMAM16-PG-(ICG)-folate, exhibited selective binding to KB cells that overexpress
folate receptors but not to SK-Br3 cells that do not express folate receptors. Thus, active
targeting using PG-based dendrimer is a promising approach towards targeted delivery and
molecular imaging.
I3 – Invited Paper
FORMATION OF REVERSE MICELLAR TYPE VERSUS SURFACE
MODIFIED SOLID LIPID NANOPARTICLES
Meike Harms, Martin A. Schubert, Ingo Friedrich, Christel C.
Müller-Goymann, TU Braunschweig, Institute for pharmaceutical
Technology, Mendelssohnstr. 1, 38106 Braunschweig, Germany,
C.Mueller-Goymann@tu-braunschweig.de
266
Solid lipid nanoparticles (SLN) - an alternative to other colloidal drug delivery systems
like, emulsions, liposomes and polymer nanoparticles – possess inherent low drug loading
capacities. In this study the amphiphilic lipid lecithin was mixed with triglycerides in order
to increase drug solubility within the lipid matrix (LM). Transmission electron microscopy
(TEM) was applied to characterize different lipid matrices. For binary mixtures of a
triglyceride and lecithin typical lamellar structures were observed. For triglycerides with
comparable low melting points additional areas with spherical structures could be detected.
This might be attributed to the existence of a solidified reverse micellar solution (SRMS).
Drug loading capacity of hydrocortisone (HC) and estradiol (EST) within these LM was
increased significantly.
Preparation of SLN where the SRMS is preserved within the particles probably results in
higher drug loading capacities. In order to obtain these SLN of a reverse micellar type
high-pressure homogenization at a temperature close to the melting temperature was
applied. Therefore at least a part of the particles might stay in solid state and its structure
including the SRMS remains unchanged. Drug loading capacities of these systems for EST
was the same as for the LM without lecithin, but for HC it was significantly increased.
Surface modified SLN are prepared by applying high-pressure homogenization at a
temperature above the melting point. This enables rearrangement of lecithin to the surface
of the oil droplets and formation of a mono- and/or multilayer around a triglyceride
206
Oral Abstracts
enriched core, resulting in surface modified SLN after recrystallisation. This model could
be proved by means of NMR and DLS measurements. In both cases liposomes resulting
from lecithin leakage into the aqueous phase could not be observed by means of TEM.
M2 – Keynote Paper
UTILIZATION OF DENSE GAS TECHNOLOGIES FOR THE
FABRICATION AND FORMULATION OF NANO-BIOMATERIALS
Neil R. Foster, School of Chemical Engineering and Industrial Chemistry, The
University of New South Wales, Sydney, NSW 2052, Australia;
n.foster@unsw.edu.au
267
The term “nano-biomaterials” is used to describe a diverse range of materials including
tissue engineering scaffolds, implant materials and drug formulations, all of which have at
least one dimension of nano- scale. Conventional methods for the fabrication of
nano-biomaterials usually involve high temperature or high shear process conditions
and/or have significant organic solvent requirements. Many of these disadvantages can be
overcome by using gas expanded liquids (GXLs) as processing media. Typically, a gas
expanded liquid is a conventional organic solvent that has been expanded with a dense gas,
such as CO2. The solvent, physical and chemical properties of GXLs are extremely tunable
and, consequently, GXLs provide an extremely powerful tool for the processing and
fabrication of complex nano-biomaterials. Fundamental characteristics of GXLs will be
described as will the methods for tuning the properties of these systems. Several examples
of nano-biomaterials processed using GXL technology will be presented.
M2 – Invited Paper
MICROENCAPSULATION THROUGH HYBRID
AQUEOUS/SUPERCRITICAL CARBON DIOXIDE PROCESSING OF
POLYMER COLLOIDS
Matthew Yates, W. Yin, X. Chen; University of Rochester, Department of
Chemical Engineering, Rochester, NY 14627; myates@che.rochester.edu
268
Several years ago, our group reported the development of a microencapsulation process
based on swelling of aqueous polymer colloids by compressed carbon dioxide. Swelling
by carbon dioxide causes the colloidal particles to enter the liquid state, facilitating mass
transport in the polymer phase. Small molecule additives can then diffuse into the polymer
particles. When carbon dioxide is slowly removed by venting, the particles return to the
glass state, entrapping the additives inside. Provided colloidal stability is maintained
throughout the process, the size and shape of colloidal particles are not significantly altered
by carbon dioxide processing. The technique represents an organic solvent-free approach
to microencapsulation, and is effective with a variety of polymers including biodegradable
poly(lactic acid). The talk will give an overview of the process, including examples of
encapsulating small molecule hydrophobic drugs into biodegradable colloids. The
challenges and progress in extending the process to hydrophilic compounds and improving
encapsulation efficiency will be discussed.
207
Oral Abstracts
M2 – Contributed Paper
EXPLORING SUPERCRITICAL FLUID TECHNOLOGY FOR THE
DEVELOPMENT OF CONTROLLED DRUG DELIVERY
Ana Rita C. Duarte,*1 Ana Luisa Simplicio, 1 Herminio C. de Sousa,2 Teresa
Casimiro,3 Ana Aguiar Ricardo,3 M. Margarida Cardoso,3 Arlette Veja
Gonzalez4, Pascale Subra4, Catarina M. M. Duarte1; 1 Nutraceuticals and
Delivery Laboratory, ITQB/IBET, Aptd. 12 – 2781-901 Oeiras, PT; 2 Dep. de
Eng. Química, FCT, Universidade de Coimbra,Pólo II – Pinhal de Marrocos,
3030-290 Coimbra, PT; 3 REQUIMTE/CQFB – Departamento de Química,
FCT-UNL, 2829 – 516 Caparica, PT; 4 Laboratoire d’Ingénierie des Materiaux
et des Hautes Pressions (LIMHP), CNRS, Institut Galilée, Université Paris
XIII, 99 Avenue Jean Baptiste Clément, 93430 Villetaneuse, France;
rduarte@itqb.unl.pt
269
Controlled drug delivery products, using biocompatible or biodegradable polymers, have
received considerable attention in the last years. These substances provide in general a
more controlled release rate of assumption of the drug by the body improving its
therapeutic action. In fact, there is a growing interest of the pharmaceutical industry in the
development of these systems. Impregnation using supercritical fluid technology has
already proven its feasibility. In this technique the drug component is dissolved in a
compressed gas (carbon dioxide) that is used as a mobile phase and that, also, swells and
stretches the polymer matrix, facilitating the diffusion of the drug, and increasing the rate
of impregnation. A high purity product, free of residual solvents is obtained, since no
organic solvents are involved in the impregnation process. In this work, the development of
successful controlled release systems is presented: supercritical impregnation of contact
lenses with ophthalmic active drugs for glaucoma treatment and the preparation of
controlled drug release systems for the delivery of a different anti-glaucomatous drug and
an anti-inflammatory drug, namely coprecipitation of Eudragit RL 100 and RS 100 with
acetazolamide and naproxen-loaded ethylcellulose/methylcellulose microspheres.
Co-precipitation of Eudragit RL 100 and RS 100 with acetazolamide was performed in a
semi pilot-scale apparatus, built for particle formation by rapid crystallisation using
supercritical carbon dioxide. Furthermore the preparation of molecularly imprinted
polymers (MIPs) using supercritical fluid technology was evaluated. Poly(diethylene
glycol dimethacrylate), was synthesised in scCO2 in the presence of different
concentrations of two different template drug molecules, salicylic acid and acetylsalicylic
acid. Results suggest that molecular imprinted polymers were successfully prepared by
supercritical polymerisation and then impregnated with the template in order to prepare
controlled release systems.
M2 – Invited Paper
LIPOSOME FORMATION WITH SUPERCRITICAL CO2 AS AN
ALTERNATIVE SOLVENT.
270
208
Oral Abstracts
Katsuto Otake, Nat. Inst. Adv. Ind. Sci. Tech. (AIST), Tsukuba, Ibaraki
305-8565, Japan; and Hideki Sakai, Masahiko Abe, Faculty of Science and
Technology, Tokyo University of Science, Yamazaki 2641, Noda, Chiba
278-8565, Japan; katsuto-otake@aist.go.jp
Supercritical carbon dioxide (scCO2) dissolves into phospholipids (PLs) to lower the
melting point by loosening the molecular interactions. With the surfactant like natures of
the PLs, essentially water –insoluble PLs become soluble in water in contact with scCO2
through the formation of CO2-in-water emulsion. The CO2-in-water emulsion becomes
liposomal dispersion by releasing the pressure due to the phase inversion. Based on this
phenomena, we have developed a process for generating liposomes that uses scCO2 as a
solvent, and named the method as “improved supercritical reverse phase evaporation
(ISCRPE)” method, from the similarity of the method with the conventional reverse phase
evaporation method. The liposomes prepared by the ISCRPE method exhibited high
trapping efficiency for both water-soluble and oil-soluble compounds. Freeze fractured
TEM observations, osmotic shrinkage measurements, and DSC measurements revealed
that the liposomes prepared by the ISCRPE method are unilamellar vesicles with loosely
packed PLs. Comparison of nitrogen with scCO2 revealed that the presence of CO2 is
necessary for the formation of liposomes. Further, scCO2 in contact with water dissolves to
form carbonic acid, causing a decrease in pH. Using these characteristics of a CO2/H2O
biphasic system, chitosan coated cationic liposomes of
L-α-dipalmitoylphosphatidylcholine were successfully prepared by the ISCRPE method.
Liposome-chitosan complexes carrying a positive charge were prepared in a single step
procedure without using acid or organic solvent, including EtOH. The liposomal
dispersion was stable at room temperature in a sealed tube for over 30 days. Details of the
ISCRPE method and its applications will be presented in the conference.
M2 – Invited Paper
SOLID DISPERSIONS BY COMPRESSED FLUID ANTISOLVENT
PRECIPITATION
Gerhard Muhrer, Novartis Pharma AG, Chemical & Analytical
Development, 4002 Basel, Switzerland; Francesco Fusaro and Marco
Mazzotti, ETH Swiss Federal Institute of Technology, Institute of Process
Engineering, 8092 Zurich, Switzerland, marco.mazzotti@ipe.mavt.ethz.ch
271
The classical anticonvulsant drug phenytoin has been used as a model compound in the
assessment of the possibility of enhancing the dissolution rate of poorly water-soluble
drugs using compressed fluid antisolvent techniques. In a first step, microcrystals of neat
phenytoin have been precipitated using both the gas antisolvent (GAS) and precipitation
with compressed antisolvent (PCA) processes. Process performances were assessed by
working out the effect of the major operating parameters on product quality, thereby
elucidating similarities and differences between the two techniques. In a second step, the
PCA process has been used to generate co-formulations of phenytoin and the hydrophilic
carrier poly(vinyl-pyrrolidone)-K30 (PVP-K30). The effect of temperature, pressure, flow
rate ratio, and drug to polymer ratio in the starting solution was investigated, yielding a
209
Oral Abstracts
variety of product morphologies. At operating conditions below the mixture critical locus
and at drug to polymer ratios of 1:2 and below, spherical nanoparticles were obtained, and
combined analysis by Raman spectroscopy, XRD and DSC revealed that phenytoin is
indeed molecularly dispersed in the polymer matrix. Results from in-vitro dissolution rate
measurements showed a substantially better performance of the co-formulations if
compared to unprocessed, neat phenytoin crystals. A comparison of the product quality of
phenytoin–PVP solid dispersions with amorphous co-formulations obtained by spray
drying again convincingly underlines the potential of dense gas antisolvent techniques for
the production of pharmaceutical formulations with enhanced oral bioavailability.
Interestingly at conditions with a drug to polymer ratios above 2:1, coated microcrystals
were obtained, which may open up new areas of application for dense gas precipitation in
drug product development.
M2 – Invited Paper
THE USE OF COMPRESSED CARBON DIOXIDE TO BROADEN THE
APPLICABILITY OF HOT STAGE EXTRUSION FOR DRUG DELIVERY
Geert Verreck1, Annelies Decorte1, Koen Heymans1, Albertina Arien1, Jef
Peeters1, Dehua Li2, David L. Tomasko2, Guy Van den Mooter1, Marcus E.
Brewster1, 1 Johnson & Johnson Pharmaceutical Research & Development,
Turnhoutseweg 30, B-2340 Beerse, Belgium; gverreck@prdbe.jnj.com 2
Department of Chemical Engineering, Ohio State University, 125 Koffolt Lab,
140 W. 19th Ave., Columbus, OH 43210, USA; gverreck@prdbe.jnj.com
272
Using a Leistritz Micro 18 intermeshing co-rotating twin-screw melt extruder, it was
shown that an optimal extruder design and screw configuration resulted in the injection of
pressurized carbon dioxide without leakage. Pressurized CO2 acted as a temporary
plasticizer during the hot stage extrusion of a number of pharmaceutical acceptable
polymers, including PVP-VA 64, eudragit® E100 and EC 20 cps. The same effect was
observed for solid dispersions with different drug loadings, consisting of itraconazole with
PVP-VA 64 and itraconazole with EC 20 cps. This plasticization was obtained under suband supercritical conditions allowing for a reduction in the processing temperature during
the hot stage extrusion process up to 65°C for EC 20 cps. Depending on pressure and
temperature, amorphous dispersions were obtained at low drug loadings, while higher
concentrations resulted in solid dispersions consisting of a mixture of glassy and
crystalline drug substance. This indicated that the morphology of the solid dispersion could
be influenced when CO2 was injected during the hot stage extrusion process. Expansion of
the injected carbon dioxide at the outlet of the extruder, resulted in a foamed extrudate.
This change in macroscopic morphology after CO2 treatment, resulted in an increased
specific surface area and porosity. As a consequence, milling efficiency was improved,
resulting in a reduction of the particle size of the CO2 treated extrudates. The in vitro drug
release of itraconazole from the 10 and 40% w/w solid dispersion could be controlled as a
function of pressure and temperature by injection of carbon dioxide during the hot stage
extrusion process.
210
Oral Abstracts
M2 – Invited Paper
FABRICATION OF LIPID NANOPARTICLES FOR LOW MOLECULAR
WEIGHT AND BIOTECH DRUG DELIVERY BY GAS COMPRESSED
TECHNIQUES
1
Paolo Caliceti, 2Nicola Elvassore, 2Alberto Bertucco, 1Alessandra
Semenzato, 1Stefano Salmaso, 1Sara Bersani – 1Pharmaceutical Sci. Dept. and
2
Chemical Eng. Dept. – Universty of Padua – Italy – paolo.caliceti@unipd.it
273
Micro- and nano-particulate solid lipid systems are promising pharmaceutical and
cosmetic formulations. They are, in fact, flexible in composition, manageable,
biocompatible and may be administered by various routes. Furthermore, solid lipid
colloidal formulations may be properly used to increase the drug stability and modulate the
release yielding successful drug delivery systems. Typically, the production of lipid
nanoparticles involves the use of high temperature necessary for melting the lipids, high
shear and pressure stresses (high shear homogenization, ultrasounds, high pressure
homogenization), surfactants and/or organic solvents (solvent emulsification/evaporation)
and lyophilization to obtain dry powders. This may limit the use of these systems in the
case of fragile drugs. Alternative techniques based on supercritical near critical and
compressed gas have been investigated. These methods operate under mild conditions
without use of harsh chemicals, yield dry products and are environmentally compatible and
industrially scalable. Typical example of this technique is Particle from Gas Saturated
Solution (PGSS). In the recent years we focused our research interest in exploiting
comprassed gas tachniques, namely PGSS, for preparation of colloidal lipid drug delivery
systems. In order to make up an operative platform, experimental/in silico investigations
aimed at defining thermodynamic parameters governing the processes were undertaken.
Materials of pharmaceutical and cosmetic interest were considered and their
physicochemical properties under the operative conditions were extrapolated by the
elaboration of DSC, solubility studies and rheological determinations. These preliminary
investigations addressed the selection of processable products and the set up of specific
equipments. Either PGSS or GAMA (Gas Micro Atomization), a newly set up process,
were appled to the nanoparticle production. Void particles as well as drug loaded
nnaoparticles were produced and characterized to evaluate their physicochemical,
morphological and biopharmaceutical properties. The results generated by this
investigation were applied to obtain products which can be succesfully exploited for both
pharmaceutical and cosmetic applications. Furthermore, the experimntatl data allow for
drawing general considerations about the applicability of these techniques for industrial
developmets.
211
Poster Abstracts
Abstracts of Poster Program
P1
274
PHARMACOKINETICS AND ANTILEISHMANIAL ACTIVITY OF
MANNOSE GRAFTED AMPHOTERICIN B LIPID NANOSPHERES
Veerareddy P Reddy, Vobalaboina Venkateswarlu, Venisetty R Kumar
University College of Pharmaceutical Sciences, Kakatiya University,
Warangal, INDIA and Nahid Ali, Indian Institute of Chemical Biology,
Kolkata, INDIA; vrk102002@yahoo.co.in
Colloidal carriers of drugs such as liposomes, nanoparticles and solid lipid nanoparticles,
have been studied as delivery systems with the aim of achieving better therapeutic efficacy
and limiting side effects of the drugs. Amphotericin B lipid nanospheres (LN-A) and
mannose grafted lipid nanospheres (LN-A-MAN) were prepared. Amphotericin B
(dissolved in methanol), mannose, egg lecithin and cholesterol were dissolved in soybean
oil, heated to 70°C on a water bath, and stirred until the system is clear. Glycerol, sucrose
and sodium oleate were dissolved in sufficient amount of distilled water and the aqueous
phase was added to the oil phase at the same temperature. A coarse emulsion was prepared
by homogenizing at 6000 rpm for 3 min and was subjected to ultrasonication. The
formulations were sterilized by autoclaving at 121oC. The pharmacokinetics and
antileshmanial activity of LN-A and LN-A-MAN were compared with amphotericin B
deoxycholate (Fungizone, marketed preparation). Same dose of each formulation (5
mg/kg) of amphotericin B was injected in the male wistar rats via tail vein. Plasma samples
were collected at different intervals. Amphotericin B showed biphasic disposition. The
pharmacokinetics of LN-A and LN-A-MAN were significantly different with fungizone.
The peak plasma concentration of LN-A and LN-A-MAN was approximately 2.5 and 3.5
folds higher than fungizone. Antileishmanial activity of LN-A and LN-A-MAN was
assessed in BALB/c mice infected with Leishmania donovani AG83 for 60 days. A single
dose of LN-A (5 mg/kg), LN-A-MAN (5 mg/kg) and fungizone (2.5 mg/kg) was injected
intravenously. Mice were sacrificed after 15 days of treatment with fungizone, LN-A,
LN-A-MAN and Leishman Donovan Unit (LDU) is counted. Fungizone, LN-A and
LN-A-MAN reduced 48 and 53; 75 and 66; and 95% and 90% of the parasite burden in
liver and spleen respectively after 15 days of infection.
P1
275
FORMULATION AND QUALITY CONTROL OF GASTRORETENTIVE
TABLETS OF RANITIDINE HYDROCHLORIDE
Janardan D, Veerareddy P Reddy, Venisetty R Kumar, Vobalaboina
Venkateswarlu, UCPS, Kakatiya University, Warangal, INDIA.
vrk102002@yahoo.co.in
Gastroretentive dosage forms are the controlled release dosage forms that release the drug
in a controlled manner thereby controlling the onset, duration and intensity of
212
Poster Abstracts
pharmacological response by pharmaceutical means, promisingly elimate the frequent
administration of dosage. Floating tablets are one of the important categories of drug
delivery systems with gastric retentive behaviour. Ranitidine is a H2 blocker and absorbed
from the upper part of GIT. Rapid metabolism after oral administration (bioavailability
50% approximately) and its need in stomach to exert local action, ranitidine hydrochloride
required to formulate as gastroretentive controlled dosage form. Six formulations of
floating tablets of ranitidine HCl were prepared by direct compression using different
concentrations HPMC K4M (hydroxy propyl methyl cellulose K4M) with effervescent
(sodium bicarbonate and citric acid), carbopol and both effervescent and carbopol. The
formulations were coded as HE1, HE2, HC1, HC2, HEC1 and HEC2. The formulations
were evaluated for weight variation, friability, hardness, content uniformity, thickness,
floating lag time and floating time. All the formulations were subjected to in vitro drug
release study and compared with that of marketed tablet. All the physical parameters
evaluated for quality control were within the acceptable limits of Indian Pharmacopoeia.
The content uniformity is in the range of 95 to 98%. The floating lag time of the prepared
formulations is good except HC1 and the floating time for all the fomulations was >24
hours except HC1 which does not floated at all. The average percent drug release from the
formulation HE2 was highest among others. In conclusion, effervescent is essential for the
formulation to have good floating property and carbopol retards the drug release in floating
formulations.
P1
276
SMART MEMBRANES FOR FLAVOR DELIVERY
Kevin A. Heitfeld, Dale W. Schaefer; University of Cincinnati, Chemical and
Materials Engineering, ML 0012, Cincinnati, OH 45221-0012, USA;
heitfeka@yahoo.com, schaefdw@email.uc.edu
Flavors often contain volatile compounds, so in the absence of encapsulation, they are vulnerable
to premature release. Encapsulation also offers protection against environmental damage such as
oxidation, light-induced reactions, etc. For processed foods, the ideal flavor would survive the
temperature excursion during cooking, remain in the product for days to months and then be
released instantaneously in the mouth. In the mouth, flavors are released due to mechanical
disruption of the gelatin encapsulant and due to enhanced permeability of the gelatin in the moist
environment. This work has focused on the use of temperature-responsive gels (TRGs) for flavor
retention at cooking temperatures. TRGs are polymeric hydrogels with a large
temperature-dependent change in volume. Specifically, we have studied a system with a lower
critical solution temperature (LCST). This type of system exhibits a two phase region at elevated
temperatures. A gel featuring a LCST exhibits swelling at low temperatures and collapse at high
temperatures. In the collapsed state, the polymer acts as a transport barrier, keeping the volatile
flavors inside. We have successfully modified a cellulose polymer to exhibit this volume change
and have encapsulated an oil phase inside the gel. Flavor transport through the particles is a major
consideration. We have studied flavor transport utilizing a vertical diffusion cell. We have
successfully modified a hydroxypropyl cellulose polymer to achieve diffusion coefficients on the
same order as sodium alginate, which is currently used in flavor encapsulation. However,
comparing the diffusivity differential of these two polymers between the high temperature and
low temperature states, HPC performs better than alginate by a factor of five.
213
Poster Abstracts
P1
277
INCREASED OSTEOBLAST FUNCTIONS ON TI NANOPATTERNED
WITH PEPTIDES
Ganesan Balasundaram, Thomas J. Webster, Division of Engineering,
Brown University, Providence, RI 02912, USA; gbala@brown.edu
In some clinical cases, the use of titanium in orthopedic implants has resulted in poor
osseointegration; specifically, the successful use of titanium as bone implants has been
limited due to nonspecific implant-tissue adhesion and subsequent scar tissue formation.
Peptide sequences such as lysine-arginine-serine-arginine (KRSR) bind transmembrane
proteoglycans (e.g., heparin sulfate) of osteoblast cells and are therefore actively being
investigated for orthopedic applications. Furthermore, nanophase materials, or materials
with consistuent particle or grain sizes less than 100 nm, are promising for various implant
applications since our tissues are composed of nanometer components (i.e., proteins and/or
inorganics). The objective of this study was to combine these two promising approaches
(peptide immobilization and the use of nanomaterials) to develop better orthopedic
materials. Peptide functionalization was conducted by means of a three step reaction
procedure: silanization with 3-aminopropyltriethoxysilane (APTES), cross-linking with
N-succinimidyl-3-maleimido propionate (SMP), and finally peptide immobilization. The
three step reaction procedure was characterized by X-ray photoelectron spectroscopy
(XPS). Scanning electron microscopy (SEM) was used to probe the surface properties of
the materials studied. Results of this study provided the first evidence of increased
osteoblast adhesion on unmodified nanophase compared to conventional metals. For all
titanium materials, results showed that the immobilization of the cell adhesive KRSR
sequence increased osteoblast adhesion compared to those non-functionalized and those
functionalized with the non cell adhesive control peptide (KSRR) after 4 hours. Further,
because osteoblast adhesion is a necessary prerequisite for subsequent functions (such as
deposition of calcium-containing mineral), the present study suggests that nanophase
metals functionalized with bioactive peptides (such as KRSR) should be further studied for
orthopedic implant applications.
P1
278
CORRELATION OF POLYMER ENERGETICS AND DRUG RELEASE
RATES
Daniel J. Burnett, Joe Domingue, and Frank Thielmann, Surface
Measurement Systems Ltd., 2222 South 12th Street, Suite D, Allentown, PA
18103 USA; and Sasa Baumgartner, Faculty of Pharmacy, University of
Ljubljana, Askerceva 7, Ljubljana, Slovenia; burnett@smsna.com
Cellulose ether polymers are common matrix compounds in sustained release tablets. The
goal of this study is to correlate surface energetic properties of the individual formulation
components measured using Inverse Gas Chromatography (IGC) with drug release profiles
of the final product. IGC is a well-established technique for quickly and accurately
214
Poster Abstracts
measuring the surface energetics for a wide range of solids. Surface energies have been
determined with various polar and non-polar vapour phase probe molecules.
Hydroxypropyl (HPC), hydroxyethyl (HEC), and hydroxypropylmethyl (HPMC) cellulose
were used as polymers and Pentoxifylline was taken as a model drug. Tablets were
prepared by direct compression of a 3:1 polymer-drug mixture. Release rates were
determined by USP 26, App. I at 37 C. Results from IGC measurements suggest that
HPMC has the highest dispersive surface energy followed by HPC and HEC. Acid-base
numbers calculated from specific interactions show the strongest basicity for HEC,
followed by HPMC and HPC. The acid numbers show the opposite trend. These trends in
the specific energy correlate well with the observed release rates. The higher the basicity
and lower the acidity the faster the release . This suggests that hydrophilic basic sites of the
polymer are responsible for the interaction with the aqueous medium. This is supported by
the specific interaction energies for the drug which are significantly lower. Therefore, the
drug-polymer interactions are less relevant for the release mechanism.
P1
279
INVESTIGATING THE KINETICS OF MOISTURE-INDUCED
CRYSTALLIZATION OF AMORPHOUS LACTOSE
Daniel J. Burnett, Joe Domingue, and Frank Thielmann, Surface
Measurement Systems Ltd., 2222 South 12th Street, Suite D, Allentown, PA
18103 USA; burnett@smsna.com
Many low molecular weight amorphous materials will revert to their thermodynamically
stable, crystalline form. This timescale of this transition is dependent on both temperature
and humidity (or solvent partial pressure). Therefore, understanding the kinetics of this
transition over a wide range of temperatures and humidity values is important for the
processing and storage of materials containing amorphous phases. Dynamic Vapor
Sorption (DVS) is a well-established method for the determination of vapor sorption
isotherms. It is based on a highly sensitive gravimetric system, which measures vapor
adsorption and desorption. In the current study water sorption experiments were
performed over a range of humidity and temperature conditions to investigate the
crystallization kinetics of a spray-dried, amorphous lactose sample. At 25 °C the onset time
to crystallization for spray-dried lactose was measured over the 48 to 60% relative
humidity range. Above 53% RH, crystalline lactose formation occurred in one step, while
a two-step process was observed at 51% RH and below. Similarly, experimetns at 51% RH
over a range of temperatures showed a two-step process at low temperatures and a one-step
mechanism at higher temperatures. Kinetic modeling indicates crystallization occurs in
two steps: (1) auto-catalyzed crystallization and (2) 3-D diffusion limited water desorption.
P1
280
SCALABLE FABRICATION OF MONODISPERSE, SHAPE-SPECIFIC
ORGANIC NANOPARTICLES FOR USE AS DELIVERY VECTORS
Ginger Denison Rothrock, Benjamin Maynor, Jason Rolland, Liquidia
Technologies, P.O. Box 110085, Research Triangle Park, NC 27709, USA; and
215
Poster Abstracts
Joseph DeSimone, University of North Carolina, CB# 3290 Venable
Laboratories, Chapel Hill, NC 27599-3290, USA;
ginger.denison@liquidia.com
To date, there has been no general particle fabrication method available that afforded
rigorous control over particle size, shape, composition, cargo and chemical structure. We
have developed scalable, “top-down” nanofabrication methodologies for the fabrication of
polymeric and organic nanostructures for nanobiotechnology and materials engineering,
utilizing the method we refer to as Particle Replication In Non-wetting Templates, or
PRINTTM. Using PRINTTM, we can fabricate monodisperse particles with simultaneous
control over structure (i.e. shape, size, composition) and function (i.e. cargo, surface
structure). PRINTTM is the first general, singular method capable of forming organic
particles that: i) are monodisperse in size and uniform shape; ii) can be molded into any
shape; iii) can be comprised of essentially any matrix material; iv) can be formed under
extremely mild conditions (and are therefore compatible with delicate cargos such as
proteins, DNA, and drugs); v) are amenable to post functionalization chemistry for the
bioconjugation of targeting ligands; and vi) are initially in an addressable array (which
opens up combinatorial approaches since the particles can be “bar-coded” using methods
similar to DNA array technologies). As such, PRINTTM is a significant scientific and
technological breakthrough which will allow the continuous fabrication of heretofore
inaccessible populations of nanomaterials, composed of organic polymers, conducting
polymers, biodegradable polymers, hydrogels, inorganic particles, natural products, and
more.
P1
281
CHEMICAL FUNCTIONALIZATION OF POLY(NITROPHENYL
ACRYLATE-CO-METHACRYLAMIDE) MICROGELS WITH
pH-SENSITIVE GROUPS AND A TARGETING LIGAND
Virginia Saez-Martinez, Leyre Perez-Alvarez, Estibaliz Hernaez, M.Teresa
Herrero, Issa Katime, Department of Physical Chemistry, Faculty of Science
and Technology, University of the Basque Country, 48940 Leioa, Vizcaya,
Spain; qfbsamav@ehu.es
The spherical morphology and nanometric size of colloidal microgels permits them to
travel in the blood stream and accumulate at tumor sites, which is interesting for anticancer
therapies standpoint.They can be chemically modified to exploit the small diference in pH
between tumors and normal tissues, and they can be coupled with targeting ligands that
interact with receptors expressed preferentially among tumor cells. Microgels in the
nanometer size range show a very fast response to environmental changes, moreover, there
have been relatively few studies of acid-swellable microgels which can be very interesting
for these therapies. In this study copolymeric microgels of nitrophenyl acrylate (NPA) and
methacrylamide (MeAM) were functionalized by chemical modification of their reactive
pendant group (NPA) in order to obtain acid-swellable and targeting micorgels. The
crosslinked microgels of poly(NPA-co-MeAM) were synthesized by precipitation
polymerization in acetonitrile. EGDMA was used as the crosslinker and AIBN as the
216
Poster Abstracts
initiator. NPA is an active ester monomer that easily reacts with amines in soft reaction
conditions. Chemical modification took place by aminolisis reaction of synthesized
poly(NPA-co-MeAM) microgels with 2-aminomethyl pyridine and
N-tert-butoxicarbonil-1,2-ethanediamine. The extent of these aminolisis reactions was
followed by UV-Vis and 1H-NMR spectroscopy. Folic acid was used as the targeting
ligand which was attached to the polymer backbone through
N-tert-butoxicarbonil-1,2-ethanediamine groups that act as spacer molecules. Microgels
swelling behavior as a function of pH was studied by Quasielastic Light Scattering
(QELS), and folic acid attachment to polymeric network was quantified by UV-Vis
spectroscopy.
P1
282
NANOPARTICLE PREPARATION OF α-LIPOIC ACID SUSCEPTIBLE
TO POLYMERIZATION
Chul Ho Park, Jonghwi Lee*; Department of Chemical Engineering and
Materials Science, Chung-Ang University, 221, Heukseok-dong, Dongjak-gu,
Seoul 156-756, Korea (South); jong@cau.ac.kr
Among various antioxidants, the redox system of alpha-lipoic acid (ALA) and
dihydrolipoic acid (DHLA) is an excellent antioxidant because both the reduced and
oxidized forms retain their functions of protecting defects related to blood flow and
neurotrophins. Recent medical studies confirmed their efficacy of not only anti-obesity but
also appetite suppression, as an overdose of ALA is taken (over 600 mg/kg). The dose
might be reduced into an acceptable range by improving the bioavailability of ALA. The
reduction of crystal sizes to nanometers in a drug delivery system can directly improve its
bioavailability. There are several restrictions in utilizing the general processes to prepare
ALA nanoparticles such as high shear homogenizing and ball milling, because cyclic
five-membered disulfide is susceptible to free radical ring-opening polymerization by
friction heat. In wet comminution, ALA of less than 0.01 M was reduced to DHLA whose
thiol (-SH) can attack the cyclic disulfide (SN2 reaction) and act as the initiator for ionic
polymerization. Therefore, this study focuses on how to prepare the nanoparticles of ALA
without any side chemical reactions like the polymerization. The temperature of
surroundings during ball milling was preserved at 4 °C in order to control that of ALA
particles below 20 °C for 4 hours. As a result, we could produce ALA nanoparticles having
the mean particle size of 300 nm with using a stabilizer, PVP (polyvinylpyrrolidone). To
prove the possible bioavailability improvement, nanoparticles and microparticles of ALA
were injected to standard rats. After 6 hours, the average amount of cumulative food intake
of rats on ALA nanoparticles was half as much as that of rats on ALA microparticles.
P1
283
SYNTHESIS, FUNCTIONALIZATION AND TRANSPORT PROPERTIES
OF MESOSTRUCTURED PARTICLES
Boon Sing Ng, Petr Vasiliev, Robert Hodgkins, Lennart Bergström.
Department of Inorganic Chemistry, Arrhenius Laboratory, Stockholm
217
Poster Abstracts
University, Stockholm SE-10691, Sweden; boonsing@inorg.su.se
Functionalized mesoporous spherical particles with a high surface area, mechanical
rigidity and chemical inertness have a great potential for a number of applications, e.g.
bioseparation and controlled drug release. There are several routes to produce these
particles where the rapid single-step, aerosol-assisted method is able to give excellent
control over the mesostructure, pore size and also offer facile and versatile approaches for
functionalization. The possibility to tune the particle size and the pore size and
mesostructure through the choice of templating amphiphilic molecule and the synthesis
conditions will be described. Characterization of the materials involves the use of
diffraction, microscopy, gas adsorption measurements and magnetic susceptibility. An
attempt will be made to relate the three-dimensional pore structure, determined from TEM,
to the transport properties of small molecules using confocal laser microscopy. An
example will also be given how superparamagnetic iron oxide nanocrystals with a suitable
surface modification can be incorporated into the mesostructured particles. The possibility
to tune the magnetic susceptibility by the amount and type of the magnetic nanoparticles
opens up many interesting applications, e.g. bioseparation. The large surface area and
extremely well defined pore size of the mesoporous material together with the possibility
to transport the particles by a magnetic field give us a very interesting possibility for
separation of specific molecules or targeted delivery.
P1
284
MOLECULARLY IMPRINTED HYDROGEL MICROSPHERES FOR
PHOSPHATE REMOVAL
Anika A. Odukale, Christopher D. Batich, University of Florida, Department
of Materials Science and Engineering, Edward A. Ross, University of Florida,
Department of Nephrology, Gainesville, Florida 32608, USA;
aodukale@ufl.edu
The ability to distinguish among molecules in solutions is central to many areas of research
and technology. One way to achieve such a system is via the use of molecularly imprinted
polymers (MIPs) that possess selective binding properties due to recognition sites within
the polymer matrix. Recently, there has been a growing appreciation for the need to avoid
calcium based oral phosphate binders in patients with end stage renal disease as to prevent
long term complications associated with elevated serum phosphate levels. Current
therapeutic agents used to alleviate this condition overwhelmingly involve the use of
nonabsorbable synthetic polymers to bind excess phosphate. However, the cost of these
agents makes it an alternative not affordable to the greater general public. Thus, MIPs
potential for enhanced stability, and selectivity that mimic natural binding phenomena,
make them an attractive cost effective option. We describe a novel technique for
developing molecularly imprinted gelatin microspheres as oral phosphate binding agents.
Using a modified general emulsion polymerization schema, and genipin as a crosslinking
agent, phosphate imprinted microspheres on the order of 20 – 100 µm can be synthesized.
After extraction of the template molecule, an imprint cavity of specific shape and memory
remains in the polymer. This cavity contains functional groups that enable targeted,
218
Poster Abstracts
high-affinity binding for phosphate to the polymer. Phosphate uptake using the gelatin
MIPs is evaluated in an in-vitro milieu that simulates human gastric conditions. The
characterization of imprinted polymers was performed using UV-VIS, light
microscope,and scanning electron microscopy techniques. Potentially therapeutic MIPs
are thus synthesized with effective phosphate imprinting, thereby demonstrating feasibility
of this novel low cost technology.
P1
285
SYNTHESIS AND CHARACTERIZATION OF SILICA
NANOPARTICLES WITH HIGH FLUORESCENCE
Michihiro Nakamura, Kazunori Ishimura, The University of Tokushima
Graduate School, Institute of Health Biosciences, Dep. of Anatomy and Cell
Biology, Kuramoto-cho, Tokushima 770-8503, Japan; Hirokazu Miyoshi, The
University of Tokushima, Radioisotope Research Center, Kuramoto-cho,
Tokushima 770-8503, Japan; and Hiroshi Satake, The University of
Tokushima, Center of Cooperative Research, Minami Jousanjima, Tokushima
770-8506, Japan;michy@basic.med.tokushima-u.ac.jp
Stable dispersions of monodisperse silica nanoparticles with high fluorescence have been
obtained using an efficient conjugation method between fluorescent dye and
3-aminopropyltriethoxysilane(APS). Fluorescent dye and APS were conjugated covalently
using chemical reaction. The silica nanoparticles were prepared from tetraethoxysilane in
mixtures of ammonia, water, ethanol, and APS-fluorescent dye conjugate. The intensities
of fluorescence of silica nanoparticles were very high and stable, and were controllable by
the change of the concentration of APS-fluorescent dye conjugate in the mixture. In
addition, silica nanoparticle with two kinds of fluorescence, e.g. fluorescein and rhodamine
G, have been also prepared successfully. The fluorescent silica nanoparticles were
characterized by fluorescence spectroscopy, fluorescence microscopy, and electron
microscopy. They showed high intensity of fluorescence, stable monodispersion,
controlled size, and mesoporus surface of nanoparticles. And some advantages of our
nanoparticle with high fluorescence will be discussed in comparison with quantum dots.
P1
286
ENZYMATIC SYNTHESIS AND CHARACTERIZATION OF NANOGELS
BY SELF-ASSEMBLY OF HYDROPHOBIZED
POLY(L-LYSINE)-AMYLOSE CONJUGATES
Nobuyuki Morimoto, Mio Yamazaki, Kazunari Akiyoshi, Institute of
Biomaterials and Bioengineering, Tokyo Medical and Dental University,
2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062, JAPAN;
mor.org@tmd.ac.jp
Nanosize hydrogels (nanogels), which are composed of submicrometer-scale gel particles,
have attracted growing interest in many biotechnological and biomedical applications. We
reported self-assembly methods for preparing physically cross-linked nanogels by the
219
Poster Abstracts
controlled association of hydrophobically modified polymers in water. For example,
cholesterol-bearing polymers such as cholesteryl group-bearing pullulan (CHP) or
cholesteryl group-bearing poly (L-lysine) form nanogels in dilute aqueous solution by
intermolecular self-assembly. Amylose, a linear polysaccharide consisting of α-1, 4 linked
glucose units, is an interesting macromolecule that forms complex with various
hydrophobic guest molecules in the helical cavity in water. Amylose derivatives can be
obtained from enzymatic polymerization by phosphorylase with maltopentaose derivatives
as primers. We reported that methoxy poly(ethylene oxide)-block-amylose
(MPEO-amylose) is a novel amphiphilic polymer having the amylose chain as a molecular
recognition site. In this study, hydrophobized poly (L-lysine) grafted maltopentaoses
(CH-MaPLL) were synthesized as amylose-primers. The partial modification of
maltopentaose-poly (L-lysine) (MaPLL) by hydrophobic cholesteryl groups leads to the
formation of nanogels (50 nm by DLS) by their self-associations. CH-MaPLL copolymers
were enzymatically polymerized in the presence of phosphorylase b and
α-D-glucose-1-phosphate. The degree of polymerization (DP) was linearly increased in
accordance to the polymerization time. Characterization and function of nanogels by
self-assembly of CH-Amylose-PLL were reported.
P1 – Invited Poster
CONTROL OF CRYSTALLIZATION FOR MEDICAL APPLICATIONS: I
CONTROL OF NUCLEATION AND GROWTH OF MAGNETITE
PARTICLES FOR CANCER HEAT IMMUNOTHERAPY. II SPHERICAL
PARTICLE-ASSEMBLY BY TWO-SOLUTION METHOD FOR DRUG
DELIVERY SYSTEM.
Yoshitake Masuda, Nagoya University, Chikusa, Nagoya, 464-8603, Japan.
AIST, National Institute of Advanced Industrial Science and Technology,
Moriyama, Nagoya, 463-8560, Japan; masuda@apchem.nagoya-u.ac.jp
287
We developed novel solution processes to control crystallization of Fe3O4 (magnetite) and
colloidal crystal. Control of nucleation and growth of magnetite particles has attracted
attentions for cancer heat immunotherapy. Spherical particle-assembly was fabricated by
newly developed two-solution method and expected to be applied in novel applications
such as photonic crystals or drug delivery system. Nucleation, growth and crystallization
of Fe3O4 (magnetite) were successfully controlled by pH modification. Magnetite
micropattern was fabricated by the site-selective deposition technique for demonstration of
magnetite crystallization control using self-assembled monolayers (SAMs) as templates.
Magnetite particles (crystallite diameter: 20 nm) were selectively deposited on Pd catalysts
which were adsorbed to the -NH2-terminated surface of a SAM, in an aqueous solution
containing iron nitrate and dimethylamine-borane. Pd colloid catalyst particles were
adhered to the amino group of a patterned SAM by electrostatic interaction. Crystalline
magnetite particulate films were then deposited on amino group regions by the effect of
metal Pd catalyst. Site-selective deposition of crystalline Fe3O4 was thus realized in an
aqueous solution. The deposition mechanism of Fe3O4 is discussed in detail in comparison
with the deposition of c-FeOOH in the solution. We further proposed a novel process to
fabricate spherical particle assemblies and their micropatterns. Hydrophilic regions of a
220
Poster Abstracts
patterned SAM were covered with methanol solution containing SiO2 particles and
immersed in decalin to control the shape of droplets and gradually dissolve the methanol
into decalin. Interfacing of methanol/decalin and shrinkage of methanol droplets were
utilized to obtain meniscus force to form spherical particle assemblies; additionally, its
static solution system allowed precise control of the conditions. Particles were assembled
to form spherical shapes on hydrophilic regions of an SAM and consequently,
micropatterns of spherical particle assemblies were successfully fabricated through
self-assembly. These processes would contribute to the advancement of particle
technology.
P1
288
SOLID LIPID NANOPARTICLES TO OVERCOME MULTI-DRUG
RESISTENCE IN CANCER THERAPY
Eun-Jung Kim, Myung-Kwan Chun, Hyo-Kyung Han, Hoo-Kyun Choi,
College of Pharmacy, Chosun University, 375 Seoseok-dong, Dong-gu,
Gwangju, South Korea; and Cheol-Hee Choi, Research Center for Resistant
Cells, Chosun University, 375 Seoseok-dong, Dong-gu, Gwangju, South
Korea; hgchoi@chosun.ac.kr, flora20@hanmail.net
The failure of chemotherapy in cancer patient is often due to the development of resistance.
Some tumor cells acquire drug resistance with exposure to structurally and functionally
unrelated drugs. This multi-drug resistance (MDR) is mainly the result of overexpression
of membrane-bound proteins that efflux drugs from the cells. MDR plays an important role
in reducing the efficacy of a drug, causing the failure of chemotherapy for the many of
cancer patients. Since most nanoparticles enter the cytosol by endocytosis, the efflux of
drug due to membrane-bound proteins may be avoided. Among nanoparticles, the solid
lipid nanoparticles (SLN) were selected for applying to anti-cancer drug delivery system
because the SLN not only has physical stability and biocompatibility but also can
incorporate a lipophilic drug by emulsification and subsequent recrystallization of the
dispersed phase. The SLN was prepared from curdlan and cacao butter using phase
inversion of curdlan by changing the pH of the solution. Curdlan, a naturally occurring
polysaccharide, was used both as a surfactant and as a shell material. Cacao butter was used
as a core material. Doxorubicin was chosen as a model anticancer drug. The in vitro release
of the drug from SLN was sustained for 4 days and the amount of released drug at pH 5 was
higher than that at pH 7.4. Even at the SLN concentration of 1 mg/ml, little cytotoxicity of
the SLN was observed for AML-2/D100, which is a resistant cancer cell. The amount of
doxorubicin accumulated in the cell from the doxorubicin-loaded SLN increased
continuously with time. Based on this result, SLN could be used to overcome MDR.
P1
289
EFFECT OF NANO-SIZING CALCIUM PHOSPHATE/CISPLATIN
COORDINATION COMPLEXES ON IN VITRO DRUG RELEASE
Liisa T. Kuhn and Xingguo Cheng University of Connecticut Health Center,
263 Farmington Avenue, Farmington, CT 06030-1615; Lkuhn@uchc.edu
221
Poster Abstracts
Intratumoral treatments of chemotherapy and a drug delivery carrier effectively localize
the chemotherapy, thereby minimizing systemic toxicity, while allowing for an increase in
drug administration. Previously, we prepared a calcium phosphate (CaP) particulate drug
delivery system for the chemotherapy drug cisplatin (CDDP) and evaluated the anti-tumor
effects in a mouse model for human cervical cancer. The large (18 gauge) needle required
to inject the micron-sized particles intratumorally led us to “nano-size” the CaP particles
through the addition of Darvan during the CaP precipitation. After a 1 hr reaction time,
dispersed 119 nm particulates were collected. The micro- and nano-particulates were
characterized TEM, FTIR, XRD, particle size analysis and zeta potential measurements.
Complexes of CaP and CDDP were prepared through electrostatic binding of an aquated
species of CDDP to the CaP particulates in a chloride-free phosphate buffer. The drug
loading was determined by platinum atomic absorption spectroscopy. Drug release studies
were completed at 4 hrs, 1d, 3d, 7d, 10d and 15 days. The nano-complexes released only
slightly more drug over the 15 day release assay (53% of the loaded drug vs. 40%) as
compared to the micron-sized complexes; however, there was desirable reduction in the
drug burst release and an extension of the sustained release. The toxicity of the released
drug from both types of CaP/CDDP was compared to that of the free drug CDDP in vitro
with the CellTiter cell proliferation assay using a mouse carcinoma cell line. IC50 values
of both complexes were found to be statistically equivalent to pure CDDP indicating no
adverse reaction between the CDDP and the nano-CaP. Lastly, nano-sizing the complexes
increased the injectibility from an 18 gauge to a 26 gauge needle which will be adequate for
animal testing. The nano-CaP/CDDP complexes are therefore ready for additional efficacy
testing in a mouse tumor model. Funded by a BCTR grant from the Susan G. Komen Breast
Cancer Foundation.
P1
290
BIODEGRADABLE POLYMERIC AGGREGATES PREPARAED BY
AMPHIPHILIC POLY(HYDROXYETHYL ASPARTAMIDE-CO-PROPYL
ASPARTAMIDE) GRAFTED WITH POLY(LACTIDE) FOR DRUG
DELIVERY
Jianhua Hu, Wei Chen, Haoran Chen, Wuli Yang, Changchun Wang,
Department of Macromolecular Science, Fudan University, and the Key
Laboratory of Molecular Engineering of Polymers, Ministry of Education,
Shanghai 200433, China; Hujh@fudan.edu.cn
In recent years, poly(aspartic acid) (PASP) has been studied in detail as a typical
hydrophilic biodegradable polymer. Its derivatives, such as poly(hydroxyethyl
aspartamide) (PHEA), poly(asparagine)-g-poly(caprolactone) et al., are totally
biodegradable, their potential applications in biological and pharmaceutical area have
explored recently. Yokoyama and his coworkers modified PASP by hydrophilic chain
poly(ethylene glycol) (PEG) at first, and then incorporation of an hydrophobic anticancer
drug to PEG-PASP to obtain amphiphilic block copolymers, which could form
nanoparticles in aqueous medium. Kim et al. and Nakato et al. reported hydrophobic
modification of PASP by grafting hydrophobic octadecyl chains and dodecyl chains onto
222
Poster Abstracts
the backbone of PSI polymers with aminolysis, respectively. After the hydrolysis of the
residual succinimide, amphiphilic copolymers were obtained, and these two amphiphilic
random copolymers could self-aggregate in water. In this paper, we report the synthesis of
new type of amphiphilic graft copolymers with a hydrophilic P(HEA-co-PA) backbone
and a hydrophobic PLA graft. Their aggregative behaviors in aqueous medium were
studied in detail by dynamic light scattering (DLS). The experimental results showed that
the grafting degree of the copolymers have a little influence on the size of the aggregates,
the particle size is around 100-200 nm. During the preparation of the aggregates, when
water was dropped into the DMF solution of P(HEA-co-PA)-g-PLA copolymers, the PLA
chains should be interact each other to form tight microdomains by either intermolecular or
intramolecular association and then the stable aggregates were formed. TEM of the
aggregates of P(HEA-co-PA)-g-PLA were conducted and clearly indicate the spherical
shape of aggregate particles. These biodegradable amphiphilic graft copolymers could be
used for drug delivery.
P1
291
SYNTHESIS, CHARACTERIZATION AND LOCALIZED SURFACE
PLASMON RESONANCE STUDY OF SILVER ORGANOSOL
Sudip Nath1, Tarasankar Pal2 and J. Manuel Perez1; 1Nanoscience Technology
Center, University of Central Florida, 12424 Research Parkway, Orlando, FL
32826,USA; 2Department of Chemistry, Indian Institute of Technology,
Kharagpur 721 302, India; snath@mail.ucf.edu
A simple and reproducible technique for the synthesis of silver nanoparticles in organic
solvent (i.e. organosol) is reported from specific a silver precursor, solid silver acetate.
Hexadecylamine in molten condition acts as a solvent for silver acetate and finally imparts
stability to the evolved nanoparticles. The amine-capped organosol shows unique stability
as neither agglomeration nor oxidation takes place over one year. The synthesized silver
particles have been characterized by UV-visible, TEM, XRD and XPS studies. The
hexadecylamine stabilized silver organosol was employed to examine the altered optical
properties in different solvent systems and ligands by accounting the changes in localized
surface plasmon resonance (LSPR) spectrum. It was observed that the position of the
surface plasmon band of silver nanoparticles is greatly affected by the solvents and ligands
under consideration. The quantitative alteration of the LSPR spectrum involving
encapsulated nanoparticles in a dielectric ligand shell has been rationalized from Mie
theory. It has also been shown that cationic and anionic surfactants of different chain
lengths induce significant changes in the optical properties of silver nanoparticles. The λmax
of the LSPR gradually shifts to red with the increase in chain length of both the cationic
and anionic surfactants, indicating specific binding of the surfactant molecules around
silver nanoparticles. Finally the affinity of the synthesized silver nanoparticles with amine
molecules has been accounted from HSAB principle into consideration.
223
Poster Abstracts
P1
292
WATER-SOLUBLE FLUORESCENT LAF3:LN3+ NANOCRYSTALS FOR
BIO-APPLICATIONS
Yong Zhang, Feng Wang, and Wee Beng Tan, Division of Bioengineering,
Faculty of Engineering, National University of Singapore, 9 Engineering Drive
1, Singapore 117576; biezy@nus.edu.sg
Use of fluorescent labeling agents has greatly assisted the study of complex biological
interactions in the field of biology. Besides commonly used fluorescent labeling agents
such as organic fluorophores and quantum dots (QDs), lanthanide-doped nanocrystals have
shown great potential to be a promising new class of fluorescent labeling agents recently.
However, lanthanide-doped nanocrystals are usually made at high temperatures or in
organic solvents, yielding products with a low processability, and as such their
bio-applications are very limited. In this study we presented a simple method for
synthesizing water-soluble lanthanide-doped LaF3 nanocrystals in aqueous solution at low
temperature. The nanocrystals had a nearly spherical shape and an average size of below
30nm. They consisted of well crystallized hexagonal phases. The LaF3 nanocrystals doped
with different lanthanide ions (Eu3+, Ce3+, Tb3+, and Nd3+) were synthesized, showing
strong luminescence in the visible (VIS) and near-infrared (NIR) spectral regions. In
particular, the LaF3:Nd3+ nanocrystals, with both the major excitation and emission peaks
located within the spectra wavelength range of 600-1100 nm (the “optical window” for
cells and tissues), have a good potential to be used as fluorescent imaging probes for cell
and animal studies.
P1
293
FLUORESCENT SILICA BEADS FOR DETECTION OF CERVICAL
CANCER
Igor Sokolov, S. Iyer, Yaroslav Kievsky, Dept. of Physics and Dept. of
Chemistry, and C. Woodworth, Dept. of Biology, Clarkson University,
Potsdam, NY 13699, USA; isokolov@clarkson.edu
Recently we have synthesized super-bright present fluorescent silica (glass) particles,
beads. The beads are a few microns glass nanoporous particles which contain florescent
dyes imbedded in the pores. The pores are self-closed, so the dye does not leak out being
sealed inside the pores. The fluorescent activity of the beads is so high that there is no need
in special fluorescent microscopy. Even ordinary dark-field microscopy mode is enough to
detect the beads. The beads are stable for many days even under direct sun light. Having
silica outside, the beads are biocompatible and can be used for labeling in-vivo. Here we
report one interesting application of these particles for detection of cervical cancer. The
cells from three different individuals (3 normal and 3 tumor) were tested for affinity. We
have developed two different methods for detecting the affinity in a Petri-dish. After
simple precipitation of the beads onto the cells, the unbounded beads removed by washing.
The next method involved using centrifugation for the removal of the unbounded beads.
Both methods show unambiguous identification of malignant versus normal cells.
224
Poster Abstracts
P1
294
DNA-TEMPLATED SELF-ASSEMBLY OF TWO DIMENSIONAL AND
PERIODICAL GOLD NANOPARTICLE ARRAYS
Jaswinder Sharma, Rahul Chhabra, Yan Liu, Yonggang Ke, and Hao Yan*,
Department of Chemistry and Biochemistry and Biodesign Institute, Arizona
State University, Tempe, AZ 85287, USA; Jaswinder.Sharma@asu.edu
Nanoparticles (NPs) are being actively developed as building blocks for electronic,
photonic and spintronics devices. When they are organized into well-defined ensembles,
their collective properties depend critically on the inter-particle spacings and their
hierarchical organization. Up to now, methods to control these parameters are scarce.
DNA-templated self-assembly provides a unique solution to meet the above challenge, due
largely to the following features of DNA and DNA-based nanostructures: DNA has
well-defined geometry and most predictable, diverse and programmable
intra/inter-molecular interactions; DNA can be modified by different chemical groups,
which act as linkers to covalently attach DNA oligomers to the NPs; the design of stiff
DNA-based nanostructures and their self-assembly have become a routine method to
construct one- and two-dimensional DNA lattices of well-defined patterns. More
specifically, when NPs are assembled onto self-assembled DNA lattices, the periodicities
and interparticle spacings defined by the DNA scaffolds can be readily adjustable, with
nanometer spatial precisions. This level of precision provides exquisite control in the
construction of rationally defined NP architectures. Here we report the first time assembly
of 5 nm Au NP functionalized with a single DNA strand on three different patterned
structural templates that are constructed from self-assembled DNA tiles. We show that the
periodicity and interparticle spacings of the NP nanoarrays can be precisely controlled by
varying the DNA tile dimensions. In our strategy, the NP-conjugated strand first
participates in the formation of a single DNA tile structure, this Au NP-bearing DNA tile
was subsequently used to assemble with another DNA tile to form three different lattice
structures, each with a well defined periodical pattern. This novel system is amenable both
to the DNA lattice formation and preventing non-specific aggregations between the Au
NPs. This development paves the way to assemble more complex nanoparticle arrays on
DNA nanoscaffolds for future device applications.
P1
295
SYNTHESIS AND CHARACTERIZATION OF POLYMERIC
MICROSPHERES OF NARROW SIZE DISTRIBUTION CONTAINING
IODINE FOR X-RAY IMAGING APPLICATIONS
Anna Galperin, Rina Ben Shabat, Shlomo Margel, Department of Chemistry,
Bar-Ilan University, Ramat-Gan 52900, Israel; ch111@mail.biu.ac.il,
Shlomo.Margel@mail.biu.ac.il
Polystyrene template microspheres of narrow size distribution ranging between
approximately 0.2 and 5.0 μm were prepared by dispersion polymerization of styrene in a
225
Poster Abstracts
mixture of ethanol and 2-methoxy ethanol, under various polymerization conditions.
Uniform radiopaque polystyrene microspheres of ca. 2.3 ± 0.2 µm were prepared by a
single-step swelling of 2.3 ± 0.2 µm polystyrene template microspheres, dispersed in an
aqueous solution with methylene chloride emulsion droplets containing
2,3,5-triodobenzoylethyl ester. After completing the swelling process, the methylene
chloride was evaporated in order to lock the 2,3,5-triodobenzoylethyl ester in the
polystyrene microspheres. The influence of the weight ratio [2,3,5-triodobenzoylethyl
ester]/[polystyrene] on the % entrapped 2,3,5-triodobenzoylethyl was elucidated.
Characterization of the radiopaque polystyrene microspheres was accomplished by light
microscope, FTIR, TGA, SEM, XPS and elemental analysis. This novel encapsulation
method of 2,3,5-triodobenzoylethyl ester within polystyrene microspheres by a single-step
swelling process may be used as a model for encapsulation of various hydrophobic
radiopaque drugs within uniform polystyrene template particles of various diameters for
different x-ray imaging applications. Likewise, 2,3,5-triiodobenzoic acid was converted to
its acrylic derivate by esterification with 2-hydroxyethyl methacrylate. The monomer,
2-methacryloyloxyethyl(2,3,5-triiodobenzoate) was then homopolymerized, using
dispersion polymerization method, in 2-methoxyethanol in presence of
polyvinylpyrrolidone as stabilizer and benzoyl peroxide as initiator, to get
poly-(2-methacryloyloxyethyl[2,3,5-triiodobenzoate]) microspheres of 0.70 µm ± 0.05.
The microspheres were characterized by FTIR, TGA, DSC, SEM, BET and elemental
analyses. The effect of some reaction parameters on various aspects of dispersion
polymerization of MAOETIB was studied. The radiopacity of the microspheres of both
types was demonstrated by an imaging technique based on x-ray absorption usually used in
hospitals. This novel radiopaque microspheres could be used for various x-ray imaging
needs, e.g. blood pool, body organs, embolization, dental composition, implants, protheses
and nanocomposites.
P1
296
INCORPORATION OF MAGNETIC PARTICLES IN POLYMER
SYSTEMS OF XYLAN
Amanda K. A. Silva, Érica L. da Silva, Juliana F. de Carvalho, Elquio E.
Oliveira, Karlyle Nalena da S. Santos, Toshiyuki N. Junior, Luiz Alberto L.
Soares, E. Sócrates T. Egito, Universidade Federal do Rio Grande do Norte,
Departamento de Farmácia, Laboratório de Sistemas Dispersos (LASID), Rua
Gal. Gustavo Cordeiro de Farias, s/n, 59010-180, Natal/RN, Brazil.
socrates@ufrnet.br; and Artur S. Carriço, Universidade Federal do Rio Grande
do Norte, Departamento de Física Teórica e Experimental, Campus
Universitário, s/n, 59072-970, Natal/RN, Brazil.
Magnetic systems with magnetite particles have been proposed for oral use as magnetic
resonance contrast agents and magnetic markers for monitoring gastrointestinal motility.
As magnetite is soluble in acid, particles may undergo dissolution at gastric pH. Regarding
pharmaceutical technology, protecting compounds from gastric environment is a key issue.
In fact, many approaches have been proposed, namely a strategy that relies on the
resistance of some polysaccharides to the digestive action of gastrointestinal enzymes. The
226
Poster Abstracts
matrices of polysaccharides are assumed to remain intact in the physiological environment
of stomach and small intestine. Once they reach the colon, bacterial polysaccharidases
come into play, and degradation of the matrices takes place. Such group of polysaccharides
is comprised of amylase, chitosan, pectin, dextran, inulin, chondoitrin, xylan, etc. The aim
of this work was to develop xylan-coated magnetic microparticles in order to protect
magnetite form gastric dissolution. Such polymer-based magnetic microparticles were
produced by emulsification/crosslinking method. The sample characterization was
performed by laser scattering particle size analysis, optical microscopy, thermogravimetric
analysis and vibrating sample magnetometry. Characterization data showed that polymeric
superparamagnetic particles were successfully produced. Polymer/magnetite ratio was
75:25. In vitro dissolution tests at gastric pH for 2h were evaluated for both magnetic
particles (MP) and polymeric magnetic particles (PMP). Dissolution rate was nearly 30%
and 3% for MP and PMP, respectively. In conclusion, the obtained results have
demonstrated the feasibility of the presented method to coat, and protect magnetite
particles from gastric dissolution. Such systems may be very promising for oral
administration.
P1
297
MAGNETITE PARTICLE DISSOLUTION AT GASTRIC pH
Amanda K. A. Silva, Érica L. da Silva, Juliana F. de Carvalho, Elquio E.
Oliveira, Karlyle Nalena da S. Santos, Toshiyuki N. Junior, Luiz Alberto L.
Soares, E. Sócrates T. Egito, Universidade Federal do Rio Grande do Norte,
Departamento de Farmácia, Laboratório de Sistemas Dispersos (LASID), Rua
Gal. Gustavo Cordeiro de Farias, s/n, 59010-180, Natal/RN, Brazil.
socrates@ufrnet.br; Artur S. Carriço, Universidade Federal do Rio Grande do
Norte, Departamento de Física Teórica e Experimental, Campus Universitário,
s/n, 59072-970, Natal/RN, Brazil.
Magnetite particles have been proposed for oral use as magnetic resonance contrast agents
and magnetic markers for monitoring gastrointestinal motility. Despite the promising
properties, magnetic particles may dissolve in acid media. The normal transit time in the
stomach (pH 1–2) is 2 h. Due to the low pH, magnetite particle dissolution may take place
during the period in which particles are in the stomach. The aim of this work was to carry
out a dissolution test to mimetize the gastric environment in order to evaluate magnetite
dissolution. First, magnetic particles were produced by coprecipitation of iron salts in
alkaline medium; then, sample characterization was performed. Characterization data
showed that the produced sample consisted of magnetite particles in the size range of 0.5-5
µm. In-vitro dissolution test was performed at 37 °C by using a rotating paddle at the
rotation speed of 100 rpm in a 0.1 M HCl solution. At regular intervals of time, aliquot
samples were withdrawn and the amount of free iron in the medium was determined by
measuring the UV absorbance at 512 nm (phenanthroline method). According to the
dissolution test, magnetite particles presented the highest dissolution rate in the early
beginning of the dissolution test, 8.8% of dissolution during the first 15 min. Then,
dissolution presented an almost linear pattern from 15 to 120 min, without reaching a
plateau. It was found that almost 30% of the sample was dissolved by 120 min. In fact, this
227
Poster Abstracts
is a striking result, considering that such high particle loss in gastric environment will
compromise particle use. In order to overcome this drawback, an enteric coating on particle
surface may be a promising approach. It is believed that coating the surface of the
magnetite particles with such material can prevent their dissolution.
Session P1
COMPOSITE THERMORESPONSIVE MICROGEL CORE DECORATED
WITH MAGNETIC NANOPARTICLES
J.E. Wong, A.K. Gaharwar, W. Richtering, Institute of Physical Chemistry,
RWTH-Aachen, Germany; D. Bahadur, Dept. of Metallurgical Engg. and
Mats. Sci., IIT-Bombay, Mumbai, India and D. Müller-Schulte, Magnamedics
GMBH, Aachen, Germany; wong@pc.rwth-aachen.de
298
Magnetic nanoparticles have recently received tremendous attention due to their potential
application, especially in the biomedical field. The driving force behind this work lies in
the possibility of encapsulating drugs or other macroions within a matrix, to then use
magnetic field to target, magnetic induction to release the drug in a controlled and diffused
manner as determined by the permeability of the shell around the matrix. We report the
synthesis and characterization of a new type of composite core-shell microcapsule. We
used the layer-by-layer technique to (i) alternately adsorb charged polyelectrolytes onto a
thermoresponsive core of a microgel, then (ii) decorate the shell consisting of
polyelectrolyte multilayers with oppositely charged magnetic nanoparticles. The magnetic
iron oxide are synthesized by co-precipitation technique and the microgel used is
Poly(N-isopropylacrylamide) (PNiPAM), synthesized by batch polymerization. The
polyelectrolytes used are poly(diallyldimethylammoniumchloride) (PDADMAC) and
poly(styrenesulfonate) (PSS). Depending on the nature of the outermost polyelectrolyte
layer, oppositely charged magnetic nanoparticles can be decorated on the
polyelectrolyte-coated microgel. Dynamic light scattering (DLS) reveals a hydrodynamic
radius of about 200 nm for the coated microgel and electrophoretic measurements confirm
charge reversal at each deposition step (+30 mV and -30 mV on deposition of PDADMAC
and PSS respectively), showing that each polyelectrolyte layer is successfully adsorbed on
the microgel. DLS confirms the overall diameter of the magnetic core-shell composite to
be around 600 nm (nanoparticles being about 90 nm in diameter). We shall show additional
characterization results such as X-Ray Diffraction (XRD), Superconducting Quantum
Interference Device (SQUID), Electron Microscopy, and thermogravitometry analysis
(TGA). Such core-shell composite particles with unique and modified properties have
promising applications in controlled, extended, and targeted delivery vehicles for drugs,
proteins, vaccines, cosmetics and food supplements.
P1
299
228
MAGNETIC NANOPARTICLES - POLYELECTROLYTE
INTERACTION : A LAYERED APPROACH FOR BIOMEDICAL
APPLICATION
A.K. Gaharwar, J.E. Wong, W. Richtering, Institute of Physical Chemistry,
Poster Abstracts
RWTH-Aachen, Germany; D. Bahadur, Dept. of Metallurgical Engg. and
Mats. Sci., IIT-Bombay, Mumbai, India and D. Müller-Schulte, Magnamedics
GMBH, Aachen, Germany; gaharwar@pc.rwth-aachen.de
Magnetic nanoparticles (MNPs) offer some unique advantages as sensing, image
enhancement, and site-specific drug delivery. However, the size, charge, and surface of
these MNPs strongly affect their applicability in the majority of the envisioned biomedical
applications. It is important that the systems are biocompatible and capable of being
functionalized for recognition of specific target sites in the body, hence the surface
modification of the MNPs with polyelectrolytes (PEs). In this work we report two different
surface modification methods. One approach is to prepare the MNPs from iron salts in
aqueous solutions in the presence of PEs to impart an in-situ PE coating. Uncoated MNPs
have positively charged surface, so the PEs used are either negatively charged
(poly(acrylic acid) (PAA) and poly(styrenesulfonate) (PSS)) or neutral (dextran). Charge
overcompensation is observed in the former case as confirmed by charge reversal obtained
from electrophoretic measurements. However in the latter case, the zeta potential is
neutral, showing that the dextran sheath effectively shields the charges on the MNPs.
Transmission electron micrographs (TEM) show that the MNPs remained discrete. The
X-ray diffraction (XRD) patterns indicate that binding of PEs do not result in any phase
change. Magnetic measurement reveals the MNPs are superparamagnetic, and their
saturation magnetisation is only slightly reduced after PE binding. The second approach is
to coat the MNPs with PE multilayers using the layer-by-layer technique. The PEs used are
polyethylenimine (PEI), poly(diallyldimethylammoniumchloride) (PDADMAC) and PSS.
Electrophoretic measurements confirm charge reversal at every stage of layering. After
every PE layer we observe not only an increase in size of the particles but also in the size
distribution. Measurements from dynamic light scattering (DLS), superconducting
quantum interference device (SQUID) and thermogravitometry analysis (TGA) will also
be discussed. Preliminary results obtained by cell incubation tests using tumor cells and
yeast cells show promising results. Fluorescence micrograph shows immediate attachment
of MNPs to the yeast cells, and they successfully aligned themselves in the presence of an
external magnetic field.
P1
300
FUNCTIONALIZED SUPERPARAMAGNETIC NANOPARTICLES AS
PATHOGEN CAPTURE PROBES
Arnold J. Kell and Benoit Simard, Steacie Institute for Molecular Sciences,
National Research Council, 100 Sussex Drive, Ottawa, Ontario, Canada K1A
0R6 and Gale Stewart, Ann Huletsky, Maurice Boissinot, and Michel
Bergeron, Centre de Recherche en Infectiologie, 2705 Boul. Laurier (RC-709),
Ste-Foy, Québec, Canada, G1V 4G2; arnold.kell@nrc.ca
Superparamagnetic nanoparticles are garnering a lot of attention in the fields of
biodiagnostics and medicine, where the development of water-soluble nanoparticles with
universal linkers allows for the covalent attachment of essentially any biological moiety to
their surfaces. Recently we have prepared silicon dioxide covered iron oxide nanoparticles
229
Poster Abstracts
(SIONs) and modified the surface of these nanoparticles with amine groups capable of
undergoing a variety of bio-conjugation reactions to endow the interface with many useful
functional groups where our goal is to develop SIONs capable of capturing pathogens from
biological samples. As such, we will briefly describe the preparative conditions employed
to optimize the amine surface coverage and stability, but the thrust of the presentation will
focus on the ability of these nanoparticles to be incorporated into a number of pathogen
capture assays. We will show that these amine-modified SIONs (A-SIONs) can efficiently
capture polystyrene (PS) beads (bacteria mimics) from aqueous solution upon covalent
attachment to the PS surface where the linking chemistry is easily controlled. A-SIONs
have also been modified with vancomycin, an antibiotic well known to interact with the
glycopeptide chains present on the surface of gram positive bacteria. These
vancomycin-modified SIONs (V-SION) are capable of magnetically confining
vancomycin antibody-modified PS beads (another bacteria mimic) as well as both gram
positive and gram negative bacteria (E. faecalis S. epidermidis and E. coli) from aqueous
solution. Though the interactions between the bacteria (and bacteria mimic) and the SION
in this case are entirely noncovalent (hydrogen bonding and electrostatic interactions),
both modified PS beads and bacteria can be readily captured through the appropriate
modification of the SION nanoparticles. Together these results indicate that SIONs hold
promise as a means of isolating pathogenic species from biological samples.
P1
301
CORE-SHELL NANOPARTICLES WITH COVALENTLY LINKED TNF
FOR CELL SIGNALLING INVESTIGATIONS
Marc Herold, Thomas Schiestel, Herwig Brunner, and Günter E. M. Tovar.
Laboratory for Biomimetic Surfaces, Fraunhofer Institute for Interfacial
Engineering and Biotechnology, Nobelstr. 12, Stuttgart, 70569, Germany,
Peter Scheurich, Klaus Pfizenmaier, Institute for Cell Biology and
Immunology, University Stuttgart, Allmandring 31, D-70569 Stuttgar;
mhe@igb.fhg.de
Cytokines play a key role in cell-cell communication. Normally they are investigated in a
soluble form or (over)expressed on the surface of a cell line. Both ways are often erroneous
as the first is an improper simplification whereas the latter usually leads to a complex
response pattern due to multiple cell-cell interactions. Objectives of this work was the
built-up of synthetic-bionic hybrid systems consisting of organically modified silica
nanoparticles and the cytokine Tumor Necrosis Factor-α (TNF) to create a defined system
for the investigation of membrane-TNF signaling. Silica particles with a size of about 100
nm were synthesized. We have modified the nanoparticles with different functional shells
to provide maleinimide groups at their surface. Free cysteine groups were introduced into
the N-terminus of TNF by recombinant methods. This approach leads to a covalent and
site-directed coupling of the protein. The resulting hybrid particles were characterized by
physicochemical and biological methods. The particles initiate cellular responses
otherwise only seen for cellmembrane-bound TNF. Thus, the hybrid Nanoparticles are
clearly showing new and cell analogous properties. These particles are thus referred to as
NANOCYTES® and are a valuable tool for biological research with high potential as a new
drug for cancer therapeutics.
230
Poster Abstracts
P1
302
NOVEL NANOPARTICLES WITH ACTIVATED ESTER SURFACE
PREPARED BY EMULSIONPOLYMERIZATION OF POLYMERIZABLE
SURFACTANTS
Marc Herold, Maria Håkanson, Herwig Brunner, and Günter E. M. Tovar,
Institute for Interfacial Engineering (IGVT), University of Stuttgart &
Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB),
Nobelstr. 12, D-70569 Stuttgart E-Mail: marc.herold@igb.fraunhofer.de
The present contribution describes the synthesis of two surfmer molecules (polymerizable
surfactants) and their use to synthesize in a one-stage reaction polymer nanoparticles for
bioconjugation. The surfmers bear activated ester groups which ensure the reactivity of the
final particles. The surfmers p-(11(acrylamido)undecanoyloxy)-phenyldimethyl
sulfoniummethylsulfate (AUPDS) and p-(11(methacrylamido)undecanoyl
oxy)-phenyldimethylsulfoniummethylsulfate (MUPDS) were characterized and their
polymerisation behaviour in emulsion copolymerisation with methylmethacrylate (MMA)
and styrene was examined. Both compounds supported the formation of positively charged
nanoparticles with a diameter in the range 100 nm to 170 nm. The composition of the
copolymer p(AUPDS-co-MMA) was determined by 1H-NMR spectrometry and elemental
analysis. Scanning electron microscopy confirmed a narrow particle size distribution. The
polymer particles were conjugated with streptavidine (SAv) and a streptavidine peroxidase
conjugate (SAv-POD) to evaluate the reactivity of the activated ester that was covalently
linked to the particle surface. Up to 28 mg Streptavidin was immobilized per 1 g particles,
binding up to (2000 ± 360) µmol biotin ligands per 1 g particles.Various other molecules
bearing N-nucleophilic groups, such as amines or hydrazides, e.g. fluoresceineamine,
n-butylhydrazide, remazol-brilliant-blue®, were immobilized at the particle surface.
P1
303
PRODUCTION OF NOVEL MULTICOMPONENT PHARMACEUTICAL
NANO AND MICROPARTICLES WITH AN AEROSOL FLOW REACTOR
METHOD
Janne Raula, David P. Brown, Anna Lähde, Esko I. Kauppinen, Center for
New Materials and Laboratory of Physics, Helsinki University of Technology,
P.O. Box 1602, FIN-02044 VTT, Finland, and Hannele Eerikäinen, Orion
Pharma, Pharmaceutical Product Development,P.O. Box 65, FIN-02101,
Espoo, Finland; janne.raula@vtt.fi
Good flowability of pharmaceutical powders is an important feature for powder handling.
Moreover, the particles should remain stable and intact to preserve their chemical and
physical properties over extended storage periods. To achieve these goals, excipient
materials such as polymers and surface-active materials are used, not only to stabilize a
drug particulate formulation, but also to reduce the interaction forces between particles.
This work presents a novel aerosol flow reactor method to produce nano and micronsized
231
Poster Abstracts
particles with matrix-type structures as well layered structures via molecular
self-assembly. In the method, the starting solution containing an active material and
expicient(s) are atomized and fed into a heated laminar flow reactor with the aid of dry or
solution-saturated carrier gas. By controlling the gas flow rate, residence times up to tens
of seconds are achieved, enabling molecular ordering such as self-assembly and
crystallization to take place. We show the production of ketoprofen and naproxen
nanoparticles stabilized with pharmaceutical polymers such as Eudragits and core-shell
type salbutamol and salt particles coated with the biocompatible peptide L-leucine at
various synthesis conditions. The shape of the latter particles varied from wrinkled to
rounded with hard and crystalline L-leucine nanocrystals on the surface. These L-leucine
crystals dramatically reduced the contact area between fine particles thus improving
flowability. Downstream of the reactor, particle size distributions were determined with
aerosol size spectrometers. Particle morphology was characterized with SEM and TEM.
P1
304
SIZE AND CONCENTRATION MONITORING OF HFA SUSPENSIONS
Philippe G. Rogueda, AstraZeneca R&D Charnwood, Bakewell Road,
Loughborough, LE11 2HD, U.K., Philippe.rogueda@astrazeneca.com. Vitaly
Buckin, Evgeny Kudryashov Ultrasonic Scientific, 1 Richview Office Park,
Clonskeagh, Dublin 14, IRELAND.
Pressure metered dose inhalers (pMDI), extensively use din the treatment of asthma, are
solutions or suspensions of micronised drugs in HFA (hydro fluoro alkanes) propellant.
The monitoring of the suspension properties of these formulations has always been an
issue. These could not be studied by traditional techniques (light based technologies),
because of their concentration and the fact that the dispersing phase is a pressurised liquid.
High Resolution Ultrasonic Spectroscopy (HRUS) has been developed to monitor the
phase separation phenomenon in these suspensions. HRUS was adapted to work with HFA
propellants, and tested on a selection of commercial pMDI suspensions: Ventolin,
Flixotide and Salbuhexal. The variation of the average particle size (Dv50) and the volume
concentration as a function of time were recorded over a duration of one hour. All
suspensions flocculated before sedimenting. The kinetics of the aggregation was very fast,
a couple of minutes, whereas full sedimentation was much slower (in excess of one hour).
It is the first time that the kinetics of the variation of the size and concentration of HFA
suspensions can be recorded quantitatively with accuracy. The application of the HRUS
technique extends beyond bench testing of HFA suspensions, and could be used for
concentration and stability monitoring of solution pMDIs, and for on-line measurements
during production. The suspension properties were compared with the delivery efficiency
of the pMDI.
P1
305
232
DISPERSION OF NOVEL INHALATION DRUG POWDERS WITH
NANOCRYSTALLINE L-LEUCINE COATING
David P. Brown, Janne Raula, Esko I. Kauppinen, Center for New Materials
Poster Abstracts
and Laboratory of Physics, Helsinki University of Technology, P.O. Box 1602,
FIN-02044 VTT, Finland, and Juha A. Kurkela, Aerosol Technology Group,
VTT Processes, P.O. Box 1602, FIN-02044 VTT, Finland; david.brown@vtt.fi
High flowability and efficient dispersion are important requirements for inhalable
pharmaceutical powders delivered by dry powder inhalers (DPI). Reduced contact area and
hard particle surfaces are known to decrease forces between fine particles and significant
research has been conducted to control and optimize physical surface properties. This work
presents a novel aerosol flow reactor method to produce inhalable drug particles (size≤5
μm) with a core-shell structure in a one step process. The composite particles consist of
salbutamol sulphate and the biocompatible peptide L-leucine. In the aerosol reactor, the
molecular arrangements such as self-assembly and crystallization of L-leucine molecules
take place resulting in the spherical drug particles becoming coated with hard and
crystalline L-leucine leafy structure. These L-leucine crystals significantly reduced the
contact area between fine particles, thus, improving flowability. This work also
demonstrates the feasibility of a novel deagglomeration device that enables to study the
deagglomeration behavior of the powders in a turbulent flow field with a constant and
continuous powder feed. Jet Reynolds numbers deagglomerating the powders varied from
8000 to 48000. The size distributions of the deagglomerated fine powders were determined
with aerosol size spectrometers. Particle morphology was characterized with SEM and
TEM. The sample powders were fed into the deagglomeration device with and without
lactose carrier particles. Salbutamol particles with L-leucine coating showed very good
deagglomeration even without carrier particles, having a fine particle fraction (FPF) up to
0.47. Moreover, these coated powders were easily fed without carriers indicating good
flowability. In general, the deagglomeration from the carrier and neighboring particles
improved with increased flow rate. However, the influence of L-leucine coating on
deagglomeration was more pronounced with less L-leucine. This is interpreted as the
interplay between the beneficial effects of surface roughness and the detrimental effects of
interlocking L-leucine leaves.
P1
306
QUANTITATIVE HARDNESS AND SURFACE CHARACTERISATION
BY ATOMIC FORCE MICROSCOPY FOR USE IN EARLY STAGE
SCREENING OF PHARMACEUTICAL FORMULATIONS
M. C. Perkins, J. Zhang, S. Y. Luk, C. E. Madden, C. J. Roberts*, N. Patel,
and A. Parker, Molecular Profiles Ltd., 8 Orchard Place, Nottingham Business
Park, Nottingham, NG8 6PX, UK; *Laboratory of Biophysics and Surface
Analysis, School of Pharmacy, University of Nottingham, Nottingham, NG7
2RD, UK; aparker@molprofiles.co.uk
Understanding the physical properties of any new active pharmaceutical ingredients (API)
is crucial in understanding the how that API will behave during processing and
formulation. As such tools that can predict these properties at early stages of development
are crucial. Atomic Force Microscopy (AFM) has been used extensively as a tool for
understanding the adhesive and cohesive properties of numerous API’s and offers a
233
Poster Abstracts
particular advantage as it has the ability to screen small quantities of material. The analysis
of these surface mediated solid-solid interactions can be extended further to provide
information on a range of important surface properties. Determination of deformation
mechanics, the accurate quantification of hardness and determination of surface energy of
pharmaceutical components from the interaction curves are demonstrated. Here we apply
nano-deformation measurements to crystals of α-lactose monohydrate to derive a
quantitative value of young’s modulus (E). This data can also be used in a qualitative
manner to describe the type of deformation a material undergoes, providing an indication
of elastic, viscoelastic and plastic deformations. These curves are also applied spatially to
locate and characterise the presence of amorphous and crystalline materials on the surface
of a modified sorbitol crystal. In the final section, we detail the measurement of the
dispersive component of the surface free-energy for purely crystalline α-monohydrate and
spray-dried amorphous lactose. The γD determined from a single crystal ((0,-1,-1) face) of
α-lactose monohydrate was 23.3 ± 2.3 mJm-2 and for the amorphous form 57.4 ± 7.9
mJm-2. These values clearly delineate the crystalline and amorphous forms of lactose.
Furthermore, these values are consistent with data previously obtained from Inverse Gas
Chromatography (IGC) and contact angle measurements. However, unlike contact angle
measurements that produce a surface measurement and IGC that biases the high energy
sites the AFM data provides access to localised measurements, such as individual faces or
in the identification and location of components within heterogeneous samples (e.g.
surface amorphous material within a crystalline sample). The AFM data presented here
indicates new opportunities for material characterisation in particular for the
characterisation of small quantities of material (ie single particles). Taken with current
advances in the application of AFM, this approach may be used to aid candidate selection
through improvements in early stage screening of API physical properties.
P1
307
PARTICLE SIZE DISTRIBUTION CHARACTERIZATION OF
SUB-MICRON SUSPENSIONS USING ELECTRON MICROSCOPY
Ben Lich, Hans Kruesemann, FEI Electron Optics B.V., 5 Achtsteweg Noord,
Eindhoven, 5600 KA, Netherlands; and Arjen Tinke, Johnson & Johnson
Research, Turnhoutseweg 30, B-2340 Beerse, Belgium; blich@nl.feico.com
In the pharmaceutical industry there is a growing tendency to develop less soluble active
ingredients (API). In order to assure acceptable in-vivo dissolution and bioavailability, a
clear trend is observed of going towards a larger specific surface area of the active
substance and thus to smaller drug particles. In order to prevent agglomeration of small
particles below ca. 1 μm, they are generally stabilized in a suspension by means of the
addition surfactants. In these cases where the dissolution of a suspension is the dominant
factor in the release mechanism of the drug, to keep the product under control it is
necessary to characterize the sub-micron or nano-size particles in terms of their particle
size distribution (PSD). Since the shape of a particle can be considered as its size
manifestation in three dimensions and since the surface/volume ratio exponentially
increases with a smaller size of the particles, for sub-micron and nano-size particles the
characterization of shape becomes increasingly important . Current size measurement
234
Poster Abstracts
techniques (e.g., Laser Diffraction) generally rely on an indirect measurement of the
particle size, and reporting of PSD data generally occurs based on the assumption that the
particles are spherical. As pharmaceutical actives are typically obtained by crystallization
and milling processes, particles are definitely non-spherical and hence there is a scientific
interest in characterizing the accurate particle size and shape. The latter yields a better
prediction and understanding of the solubility of the active ingredients and hence will lead
to improved drug formulations. In this study for rather wide size distributions of a
sub-micron suspension in water we present very promising results based on expanding the
“seeing is believing” addagium, i.e. scanning electron microscopy images are used not
only for qualitative purposes, but also for the quantitative particle size distribution analysis
of a pharmaceutical sub-micron suspension. The effects of sample preparation, image
acquisition conditions and image processing are evaluated. In particular, the
consequences related to the choice of filters, imaging vacuum mode and detector
technology will be discussed in more detail.
P1
308
METHODS FOR CHARACTERIZATION OF MICRO- AND NANO-SIZED
PARTICLES AND CAPSULES
Holger Woehlecke, Dietmar Lerche, Dr. Lerche KG, Rudower Chaussee 29,
D-12489 Berlin, Germany; and Rudolf Ehwald, Humboldt-University, Institute
of Biology, Invalidenstr. 42, D-10115 Berlin, Germany;
office@lerche-biotec.com
Microparticles and microcapsules have found a broad spectrum of applications, each of
which requiring special physical properties as mechanical behavior and permeability
characteristics. A complex of methods is presented to analyze these important properties.
For complex characterization of size exclusion limits (cut-off) and size dependent
permeability of permeable molecules the authors developed a fast and convenient method
based on high-resolution gel permeation chromatography. The permeability of narrow size
fractions of a polydisperse polymer solution is measured synchronously by this method.
Different texture properties of microcapsules and –beads in a diameter range from 500 to
5000 µm can be easily characterized by compression analysis of single particles by means
of the LUMiTexture. This includes e.g. burst point and apparent interfacial tension of
microcapsules and -spheres. Furthermore we report on a new method for evaluation of the
elasticity/deformability of capsules and small particles to quantify packing, compression
and dilatation behavior. This method is based on sedimentation analysis by means of an
analytical centrifuge LUMiSizer®. This device has an integrated optic-electronic sensor
system and allows for analysis of spatial and temporal changes of light transmission during
centrifugation of particle suspensions. This system also allows for measuring of particle
size. The presented methods can be useful for screening of new particle and capsule
membrane materials for special applications and for the characterization and certification
of new products. The authors are interested in co-operation. Work was supported in part by
project “Werkzeuge zur Applikation von 3-D-Zellkulturen” EFRE and Berlin (Profit
10129304).
235
Poster Abstracts
P1
CHARACTERISING BICONTINUOUS CUBIC NANOPARTICLES BY
CRYO FIELD EMISSION SCANNING ELECTRON MICROSCOPY
Shakila Rizwan1, Charlie Dong2, Ben Boyd2, Sarah Hook1 and Thomas
Rades1
1
New Zealand’s National School of Pharmacy, University of Otago, Dunedin
2
Department of Pharmaceutics Victorian College of Pharmacy, Monash
University, Victoria
Lyotropic liquid crystals are complex systems formed by the assembly of amphiphilic
molecules in solvent rich systems (usually water) into various geometries. The most
common geometries include the lamellar, the cubic and the hexagonal phase. The phase we
are interested in is the bicontinuous cubic phase, which in the presence of excess water may
be dispersed into nanoparticles known as cubosomes. Cubosomes are a novel lipid
particulate delivery system currently being investigated for drug delivery purposes. They
offer distinctly different properties over conventional lipid based particulate systems such
as liposomes or emulsions. The particles have two water channels, a hydrocarbon chain
region and an interfacial head group that allows for incorporation of hydrophobic,
hydrophilic or amphiphilic compound. Previously cubosomes have been characterized by
cryo transmission electron microscopy (cryo TEM) with small angle x-ray diffraction
(SAXS) confirming the bicontinuous liquid crystalline type. The present study aims to
characterize bicontinuous liquid crystalline nanoparticles by the novel method of cryo field
emission scanning electron microscopy (cryo FESEM). Bulk cubic phase and cubosomes
were prepared and analysed using cryo FESEM and SAXS. The results show the tortuous,
bicontinuous nature of the cubic phase with a non intersecting network of water channels
similar to the mathematical description of the bicontinuous cubic phase. Particles also
show the same underlying tortuous structure entirely consistent with that of the bulk cubic
phase. Cryo FESEM provides valuable insight into the morphological features, which to
date have only been demonstrated mathematically. We are able to show with this technique
the unique details of these systems and provide strength to support the nodal surface
representation of bicontinuous cubic liquid crystalline systems.
309
P1
310
CHARACTERIZATION OF METAL DEPOSITION ON
NANOPARTICLES AT SINGLE PARTICLE LEVEL
Grit Festag, Andrea Csáki, Thomas Schüler, Robert Möller, Wolfgang
Fritzsche, Institute for Physical High Technology (IPHT), Photonic Chip
Systems Dep. A.-Einstein-Str. 9, 07745 Jena, fritzsche@ipht-jena.de
Metal nanoparticles, especially gold nanoparticles have been used as labels in electron and
light microscopy for many years. Nowadays, they have generated considerable interest for
numerous processes in molecular construction as well as in various kinds of bioanalytical
methods. Thereby, specific reductive deposition of silver or gold on the nanoparticles has a
tremendous importance for signal enhancement. Although a variety of metal enhancement
methods have been established there are still few data about the rate, intensity, and
236
Poster Abstracts
specificity of their enhancement effect. For characterizing we non-specifically
immobilized gold nanoparticles on silicon oxide and enhanced them by different
commercial and homemade metal salt solutions. Atomic force microscopy (AFM) was
used to study this process at the single particle level in order to reveal the influence of
parameters like particle size, composition of enhancement solution, length of incubation
etc.. Because on-line measurements were not feasible, techniques were developed to
relocate certain positions at the sample in order to image particle arrangements after every
enhancement step. We could demonstrate that the examined metal enhancement methods
considerably differed in enhancement velocity, homogeneity, and specificity. We extended
these studies to an investigation of enzymatic metal deposition. Thereby an enzyme
complex catalyzes the growth of a metal layer. We compared the enzymatic and the
particle-induced deposition regarding growth kinetics and specificity of the reaction with
special emphasis of a possible application in an electrical chip-based DNA detection.
P1
311
ADHESION FORCES BETWEEN HYBRID COLLOIDAL PARTICLES AND
CONCANAVALIN A
L. B. R. Castro1, 2 and D.F.S. Petri1, 1Instituto de Química, Universidade de São
Paulo, Brazil; 2Max Planck Institut for Polymer Research, Mainz, Germany;
dfsp@usp.br
Hybrid particles of poly(methyl methacrylate) and carboxymethylcellulose, PMMA/CMC were
attached to atomic force microscopy cantilevers and probed against Concanavalin A (ConA)
films formed either on Si wafers or on CMC substrate. Regardless the substrate, the approach
curves showed different inclinations, indicating that the probe first touches a soft surface and then
a hard substrate. The distance corresponding to the soft layer was estimated as (20 ± 10) nm and
was attributed to the CMC layers attached to the hybrid particles surfaces. Probing PMMA/CMC
particles against ConA adsorbed onto Si wafers yielded retract curves with a sawlike pattern. The
average range of adhesion forces (maximum pull-off distance) and mean adhesion force were
estimated as (100 ± 40) nm and –(11 ± 7) nN, respectively, evidencing multiple adhesions
between CMC sugar residues and ConA. However, upon probing against ConA adsorbed onto
CMC substrates the mean pull-off distance and mean adhesion force were reduced to (37 ± 18)
nm and –(3 ± 1) nN, respectively, indicating that the ConA molecules immobilized onto CMC
films are less available to interact with the hybrid particle than the ConA molecules adsorbed
onto Si wafers. Another set of experiments, where PMMA/CMC particle probed against
ConA-covered Si wafers in the presence of mannose, showed that the addition of mannose led to
a considerable decrease in the mean adhesion force from – (11 ± 7) nN to – (3 ± 1) nN. Two
hypotheses have been considered to explain the effect caused by mannose addition. The first
suggested the desorption of ConA from the substrate, so that the hybrid particle would probe bare
Si wafer (weak adhesion). The second proposed the adsorption of mannose onto ConA layer and
onto CMC at the surface of hybrid particle, so that mannose layer would probe against another
mannose layer, leading to low adhesion forces. In situ ellipsometry and capillary electrophoresis
have been applied to check the hypotheses.
237
Poster Abstracts
P1
312
INVESTIGATION OF THE PARTICLE SIZE DISTRIBUTION AND ZETA
POTENTIAL OF ALUMINUM HYDROXIDE ADJUVANT FOLLOWING
FREEZE DRYING AND FREEZE THAWING
Amber Clausi, Scott Merkley, and Theodore Randolph, Department of Chemical
and Biological Engineering, UCB 424, University of Colorado, Boulder, CO 80309;
amber.clausi@colorado.edu
Protein-based therapeutics often require a lyophilized formulation to ensure adequate long-term
stability. However, it has been reported that aluminum-based adjuvant salts, an essential
component of vaccine formulations, aggregate upon freezing and thus preventing their use. The
purpose of this study is to examine the effect of cooling rate on the particle size distribution and
zeta potential of aluminum hydroxide adjuvant particles. Two cooling rates were utilized: a slow
cooling utilizing a lyophilizer with a 0.5 ºC/min ramp rate, and a faster cooling rate obtained by
dripping the solution into liquid nitrogen. Samples were analyzed following a freeze/thaw cycle
and following freeze drying utilizing both cooling methods. It was found that the slower cooling
rate results in aggregation of the aluminum hydroxide particles with an order-of-magnitude
increase in particle diameter. These effects are minimized through the faster cooling rates of the
dripped solutions with a particle size distribution similar to that of the liquid formulation. The
aggregation in the tray cooled samples is strongly dependant on the trehalose concentration in the
formulation, with high trehalose concentrations preventing aggregation, but the ionic strength of
the solution has little effect. No additional aggregation is seen following drying or reconstitution
of the dried product, indicating that it is induced during freezing. The aggregation in the tray
frozen samples is accompanied by a decrease in the zeta potential of the particles, whereas no
significant decrease in zeta potential was seen for the drip freeze dried samples when compared to
the liquid. It was also seen that the zeta potential of the aluminum hydroxide particles in
succinate buffer decrease over a two-week aging period indicating a possible surface substitution
of hydroxyl and succinate groups when stored as a liquid.
P1
313
INCORPORATION OF HYDROPHILIC COMPOUNDS IN SOLID LIPID
PARTICLES USING SUPERCRITICAL FLUID TECHNOLOGY
A.R. Sampaio de Sousa1, Ana A. Matias1, Hermínio C. de Sousa2, Catarina M.M.
Duarte1*; 1Nutraceuticals and Delivery Laboratory, ITQB/IBET, Aptd. 12 – 2780
Oeiras, Portugal; 2Departamento de Engenharia Química, FCT-Univ.Coimbra, Polo
2 – Pinhal de Marrocos, 3030-290 Coimbra, Portugal; cduarte@itqb.unl.pt,
rsousa@itqb.unl.pt
Supercritical fluids (SCF) are a clean and environmentally friendly technology which has been
shown to be a viable option in the formulation of particulate delivery systems, such as
microparticles and nanoparticles, liposomes, and inclusion complexes, which control the delivery
and/or enhance the stability of labile compounds. The advantages of SCF technology include use
of mild operating conditions, the use of benign nontoxic materials (such as CO2), and the
minimization of organic solvent use and production of particles with controllable morphology,
narrow size distribution, and low static charge. The technique used in this work, PGSS® 238
Poster Abstracts
Particles from Gas Saturated Solutions seems to be one of the most promising methods of particle
formation with supercritical fluids, allowing the generation of particles from a great variety of
substances that need not to be soluble in supercritical carbon dioxide. In this method, CO2 is
incorporated in the bulk of a melted matrix, whose melting point can be significantly decreased
by the presence of CO2, creating a gas-saturated solution that can be expanded through a nozzle
generating solid particles. The aim of this study was to incorporate hydrophilic compounds, such
as ascorbic acid and powerful antioxidants obtained from olive by-products, in lipid particles.
Lipids are extremely promising carriers that can improve the in vivo properties of bioactive
ingredients and facilitate the incorporation of the compounds in hydrophobic media as oily
products. All the lipid matrices used, as well as emulsifiers, are considered to be GRAS
excipients. The particles obtained were analysed in terms of structure (SEM), particle size (PCS),
water content and active compound content.
P1
314
ACETAZOLAMIDE CONTROLLED RELEASE FROM MICROPARTICLES
PREPARED BY SAS
Ana Rita C. Duarte, Catarina M. M. Duarte1, Arlette Vega-González*, Pascale
Subra2; 1Nutraceuticals and Delivery Laboratory, ITQB/IBET, Aptd. 12 – 2780
Oeiras, Portugal; 2Laboratoire d’Ingénierie des Matériaux et des Hautes Pressions,
C.N.R.S., Institut Galilée, Université Paris XIII, 99 Avenue Jean Baptiste Clément,
93430 Villetaneuse, France ; vega@limhp.univ-paris13.fr; cduarte@itqb.unl.pt
Microparticles of Eudragit RS and Eudragit RL co-precipitated with acetazolamide were
prepared using the supercritical anti-solvent technique (SAS). Composite particles of Eudragit
RS 100 with acetazolamide and Eudragit RL 100 with acetazolamide, as well as mixtures of the
polymers (50:50; 70:30 and 30:70) were coprecipitated with acetazolamide. In all experiments
the ratio polymer:drug was 2:1. The drug release of acetazolamide from the particles prepared
was evaluated. Results suggest that a controlled release system for this drug was successfully
prepared and the rate of drug release could be controlled to some extent by the addition of
different polymer ratios. The release profiles were modelled with Fick’s law of diffusion and
Power law. The systems studied present a release mechanism controlled by drug diffusion, which
complies with Fick’s law of diffusion.
P1
315
PHARMACOLOGICAL AND HISTOLOGICAL EVALUTION OF
HYDROXYPROPYL-β-CYCLODEXTRIN-BUPIVACAINE INCLUSION
COMPLEX
Daniele R. de Araujo1, Cíntia M. S. Cereda1, Giovana R. Tofoli2, Leonardo F.
Fraceto 1,3, José Ranali2, Angélica F. A. Braga4 and Eneida de Paula1; 1 State
University of Campinas, Dept. of Biochem., Cidade Universitária Zeferino Vaz s/n,
Campinas, SP, Brazil; 2 State University of Campinas, Dept.of Physiological
Sciences, Av. Limeira 901, Piracicaba, SP, Brazil; 3 University of Sorocaba, Dept. of
Pharmacy, Rod. Raposo Tavares, Km 92,5; Sorocaba, SP, Brazil; 4 State University
of Campinas, Dept. of Anesthesiol., Cidade Universitária Zeferino Vaz s/n,
239
Poster Abstracts
Campinas, SP, Brazil; giovanatofoli@fop.unicamp.br; depaula@unicamp.br
Bupivacaine (BVC) is probably the most extensively used local anesthetic (LA) in surgical
procedures worldwide. Development of LA in carriers such as beta-cyclodextrin (β-CD) has been
used as an alternative for the treatment of pain, prolonging the anesthetic effect and reducing its
toxicity. In the search for safer LA formulation we have prepared a complex of BVC in
hydroxypropyl-β- CD (HPβ- CD). This study compared the anesthetic effect of this inclusion
complex as against BVC in solution. The complex was obtained by mixing equimolar amounts of
HPβ- CD and BVC to a final 0.5% BVC concentration. Motor and sensory blockades induced by
plain and complexed BVC were assessed after intrathecal administration in rats, using the
paw-pressure test. A histological analysis of the kidneys was performed in animals treated with
0.5% BVCHPβ- CD , BVC or HPβ- CD, in order to evaluate the nephrotoxicity of HPβ- CD. In vivo
experiments showed that the latency time for motor blockade was significantly reduced after
treatment with BVCHPβ- CD (p<0.001 when compared with BVC), and no changes in: time for
recovery, time for maximum effect and total effect. Moreover, BVCHPβ- CD enhanced the intensity
(1.5 fold, p<0.001) and prolonged the duration of analgesia in relation to BVC. Histological
images did not reveal any morphologic changes after treatment of the animals with HPβ- CD,
BVC or BVCHPβ- CD . The BVCHPβ- CD inclusion complex improved the differential nerve
blockade without evoking nephrotoxicity in rats.
P1
316
IN VITRO TESTING OF VASCULAR SMOOTH MUSCLE CELLS
EXPOSED TO UNMODIFIED MULTIWALLED CARBON NANOTUBES
Tammy Oreskovic, Paul Rice and Natalia Varaksa, National Institute of
Standards and Technology, Materials Reliability Division, Boulder, Colorado
80305, USA; oreskov@boulder.nist.gov
Carbon nanotubes (CNTs) have superior structural, mechanical and electrical properties
that are of great interest for medical and biological applications. Promising areas include
drug delivery, therapeutics, tissue engineering, biosensors and probes. For most
applications, modification of the CNT surface is required to improve stability and ease of
dispersion in aqueous solutions. This surface modification often alters the physical
properties of the CNTs and may obscure the actual interaction of pristine CNTs with living
systems. Additionally, this new surface (i.e., chemically modified) may change once
introduced into the biological environment through metabolic interactions and/or
enzymatic breakdown of the surface. As a precursor to evaluating surface modification of
CNTs we first exposed unmodified multiwalled carbon nanotubes (MWCNTs) to vascular
smooth muscle cells (VSMCs). Varying densities of MWCNTs were applied by a spraying
technique to glass substrates. VSMC cell growth was monitored over the course of days
with a proliferation assay to assess cell metabolic activity. Cell cultures were examined by
optical and scanning electron microscopy. From these studies we have found that cells did
not attach to MWCNTs as well as controls (glass substrates). However, VSMCs still
remained viable based on the proliferation tests and microscopic imaging. Further studies
will include use of different cell types and various markers of cell proliferation to better
quantify changes in cells over extended periods of time.
240
Poster Abstracts
P1
317
NANOCARE - CHANCES AND RISKS OF NANOMATERIALS
Regine Hedderich, Forschungszentrum Karlsruhe, NanoMat, PO Box 3640,
Karlsruhe D76021, Germany; Regine.Hedderich@nanomikro.fzk.de
One of the main challenges facing nanotechnology is to investigate the health effects of
nanomaterials. NanoMat, based at the Forschungszentrum Karlsruhe (www.nanomat.de),
has about 25 partners from research institutions and industry working on the theme: “The
synthesis and investigation of nanostructured metals and ceramics and the materials and
functions arising from their nanoscale nature.” NanoMat is ideally placed as:
•
A meeting point for research and industry
•
An independent institution oriented to the public interest
•
All the relevant subject areas are represented at the Forschungszentrum Karlsruhe
(Synthesis and Characterisation of Nanomaterials, Toxicology, Technology Assessment)
complemented by activities of the other partners.
•
Optimisation of the lifecycles of nanomaterials (sustainable development,
toxicology, and economic use)
•
NanoVision (2003, 2004, 2005, 2006) Interdisciplinary workshop annually
NanoCare is a project funded by the BMBF and will aid the generation of new scientific
knowledge on possible health effects of nanoparticles. Sixteen partners from research and
industry are involved. NanoCare is coordinated by the Karlsruhe Research Center and
NanoMat. In order to establish a unique information base “Environmental and health
effects of nanoparticles” a most comprehensive collection of relevant data will be made,
which will be assessed and presented online in an easy access format. NanoCare has a three
stage approach:
(1) Knowledge Generation - Collection of primary data of health effects of nanoparticles in
the workplace. Information from particle analyses, biological test systems and
deagglomeration behaviour;
(2) Knowledge Management - The collection and categorisation of characteristic
parameters for the creation of a scientific knowledge base. In a second stage the
information obtained will be catalogued according to target groups (journalists, scientists,
public) and made available in the form of a data bank; and
(3) Knowledge Transfer - The data bank will be made public in a user friendly form.
Seminars, conferences and workshops will ensure an active dialogue between research,
industry and the general public (www.nanopartikel.info).
P2
320
SURFACE FUNCTIONALIZATION OF MAGNETIC NANOPARTICLES
VIA SURFACE-INITIATED ATOM-TRANSFER RADICAL
POLYMERIZATION (ATRP)
Shy Chyi Wuang, Feixiong Hu, Koon Gee Neoh*, En-Tang Kang,
Department of Chemical and Biomolecular Engineering, National University
of Singapore 10 Kent Ridge, Singapore 119260; g0403162@nus.edu.sg
The potential of using superparamagnetic magnetite nanoparticles for biomedical
241
Poster Abstracts
applications can be increased by grafting with biocompatible polymers. The application of
the ATRP technique to achieve grafting of two different polymeric brushes,
poly(poly(ethylene glycol) monomethacrylate) (P(PEGMA)) and
poly(N-isopropylacrylamide) (P(NIPAAM)), was demonstrated with different initiators.
The modified nanoparticles were characterized using Fourier transform infra-red
spectroscopy, X-ray photoelectron spectroscopy, vibrating sample magnetometer and
thermogravimetric analysis. The results indicate that ATRP is an effective way of
controlling the grafting of biocompatible polymers. The P(PEGMA)-functionalized
nanoparticles were assessed for their ability to reduce phagocytosis by macrophages in
vitro. It was found that the uptake of these functionalized nanoparticles by macrophages
was greatly reduced from 158 pg/cell for the pristine magnetite nanoparticles to <2 pg/cell
after grafting with P(PEGMA). Since increasing plasma half-life is a challenge
encountered in in vivo applications of nanoparticles, the P(PEGMA)-functionalized
nanoparticles offer a distinct advantage in this aspect. No cytotoxicity effects were
observed with the macrophages after incubation with the P(PEGMA)-functionalized
nanoparticles. On the other hand, the P(NIPAAM)-functionalized nanoparticles can serve
as an anchor for the subsequent attachment of other biomolecules such as heparin. These
results demonstrate how magnetite nanoparticles can be surface modified via ATRP to
tailor for potential biomedical applications.
P2
321
COLLOIDAL DELIVERY SYSTEMS FOR FUNCTIONAL FOODS
Krassimir P. Velikov, UFHRI, Unilever R&D Vlaardingen, The Netherlands;
Krassimir.Velikov@Unilever.com
The growing demand for functional foods is largely driven by the increasing knowledge of
the ingredients and their impact on physiological functions and health. The design of
functional foods, however, brings enormous challenge for the food industry. The delivery
of nutraceuticals required to design functional foods is a technological challenge for food
industries, as similarly encountered in the pharmaceutical industry. The incorporation of
nutraceuticals (e.g. nutrients or bioactive molecules) can compromise the product
functionality. The issues are often related to solubility, taste, and stability of the functional
ingredient or unwanted changes in the product stability, appearance, and taste due to
interactions with other ingredients. The incorporation of minerals supplement in food
products, for example, can cause changes in taste, lipid oxidation, color changes, and
physico-chemical instability. In this talk, some examples will be given on how some of the
above mentioned issues can be addressed by using colloidal delivery systems. The
fabrication, characterization, properties, and stability of colloidal delivery systems for iron
will be discussed in detail.
P2
322
242
TEMPLATE-ASSISTED SELF-ASSEMBLY OF POLYMERIZABLE LIPID
NANOTUBES
Ali M. Alaouie, Alex I. Smirnov, Department of Chemistry, North Carolina
Poster Abstracts
State University, 2620 Yarbrough Drive, Campus Box 8204, Raleigh, NC
27695-8204, USA; Alex_Smirnov@ncsu.edu
Mixtures of certain synthetic phospholipids, such as, for example, diacetylenic and
short-chain saturated lipids, are known to form ribbons and nanotubes in solution.
Formation of these unusual bilayer phases is known to be dependent upon lipid
concentration, structure and other experimental conditions. The lipid in these structures
could be polymerized by exposing the sample to an ultraviolet light. Previously, we have
shown that under certain conditions many phospholipids would self-assemble into a
nanotube when placed inside a nanopore. For macroscopically homogeneous and
uniformly packed nanopores, such as anodic aluminum oxide (AAO) these lipid nanotubes
form arrays that could be used in combinatorial assays. Here we demonstrate that the
mixtures of diacetylenic and short-chain saturated lipids could be deposited inside
nanoporous AAO and then polymerized. Moreover, the AAO substrate can then be
removed either partially or completely releasing structures formed. We characterize
formation of AAO-templated polymerized lipid assemblies with UV-vis and SEM. The
nanopore diameter of nanoporous AAO substrate could be varied and this could be utilized
to attenuate phospholipid self-assembly. We also discuss potential use of
template-assembled polymerized lipid nanostructures. DOE Contract
DE-FG02-02ER15354 to A.I.S.
P2
323
THE UPTAKE MECHANISM OF AN APOE-DERIVED PEPTIDE
DEPENDS ON ITS AGGREGATIONAL STATE
Eik Leupold, Sandro Keller, Heike Nikolenko, Michael Bienert, and Margitta
Dathe, Leibniz Institute of Molecular Pharmacology (FMP),
Robert-Rössle-Str. 10, 13125 Berlin, Germany; Leupold@fmp-berlin.de
Specific and controllable drug targeting has long been recognized as a crucial issue but also
as a major obstacle in the application of numerous therapeutics. Supramolecular structures,
particularly micelles and liposomes equipped with uptake mediating address compounds,
have attracted much attention as pharmaceutical formulations for the administration of
otherwise only poorly soluble, rapidly degradable, or even toxic effector molecules. Here
we introduce a novel peptide vector derived from the low-density lipoprotein receptor
(LDLr)-binding domain of apolipoprotein E (apoE). The highly cationic tandem peptide
(A2) acquires upon coupling of two hydrophobic palmitoyl chains (P2) detergent-like
properties, such as a strong tendency for self-association and the ability to integrate into
lipid bilayers. Light scattering and isothermal titration calorimetry studies shed light on
lipopeptide (P2A2)-lipid interactions and yielded a phase diagram with three well-confined
areas ascribed to micellar, transition, and vesicular ranges, permitting mastery of the
colloidal state. Owing to its straightforward synthesis, its unique physicochemical
properties, and its adaptability to a broad spectrum of targets, P2A2 is a highly promising
candidate for the development of micellar and liposomal drug delivery systems. Confocal
laser scanning microscopy demonstrated the efficient internalization of free A2, micellar
P2A2 and liposome bound P2A2 into mouse brain capillary endothelial cells. For further
243
Poster Abstracts
elucidation and comparison of the corresponding uptake mechanisms we performed uptake
experiments under various conditions, e.g. low temperature, energy depletion, and in
presence of specific endocytosis inhibitors. These revealed a clear energy dependent
uptake mechanism for A2 in all three aggregational states, but also striking differences in
the individual endocytotic pathways, providing a basis for target specific drug
administration.
P2
324
QUANTIFYING LOW LEVELS OF AMORPHOUS CONTENT USING
VAPOR SORPTION TECHNIQUES
Daniel J. Burnett, Joe Domingue, and Frank Thielmann, Surface Measurement
Systems Ltd., 2222 South 12th Street, Suite D, Allentown, PA 18103 USA;
burnett@smsna.com
Amorphous materials in pharmaceutical formulations yield complex and challenging
problems concerning the performance, processing, and storage of these products. The
presence of amorphous materials can be wanted or unwanted, depending on the desired or
undesired unique properties of the amorphous phase. For these reasons, determining the
amount of amorphous material is critical in the formulation of pharmaceutical powders.
Dynamic gramivetric vapor sorption (DVS) is a well-established method for the
determination of vapor sorption properties. It is based on a highly sensitive gravimetric
system, which measures the adsorption and desorption of extremely small amounts of
probe molecule. There are several gravimetric methods available in the literature to
quantify amorphous contents. One method measures the vapor uptake of a (partially)
amorphous sample before and after a solvent-induced crystallization event. Another
method compares the relative uptakes of the amorphous and crystalline phases without
crystallizing the amorphous material. A third method necessitates the formation of a
hydrate or solvate to quantify amorphous contents. In the current studies vapor uptakes
were collected on trehalose samples with various amounts of amorphous material. The
various available methods will be compared and discussed. All methods were able to
detect amorphous contents below 5%.
P2
325
INVESTIGATING THE EFFECTS OF PROTEIN CONCENTRATION ON
THE GLASS TRANSITION BEHAVIOR OF LYOPHILIZED
PROTEIN-SUGAR FORMULATIONS
Daniel J. Burnett, Joe Domingue, and Frank Thielmann, Surface Measurement
Systems Ltd., 2222 South 12th Street, Suite D, Allentown, PA 18103 USA;
Andrew Ingham and Kevin Ward, Biopharma Technology Ltd., Winnall
Valley Road, Winchester SO23 0OL UK; burnett@smsna.com
The successful utilization of proteins as pharmaceutical formulations presents significant
challenges in maintaining formulation stability. As a result, proteins are often
co-lyophilized in sugar matrices for added stability. Ultimately, the interactions between
244
Poster Abstracts
the incorporated sugars and the protein determine the formulation stability. The
formulation’s glass transition (Tg) is commonly used to evaluate the physical stability of
amorphous materials. The Tg can be greatly affected by the moisture content; therefore
investigation of the water sorption behavior for these protein-sugar formulations is
paramount in determining the ultimate product stability. Dynamic Vapor Sorption (DVS)
is a well-established gravimetric method for the determination of vapor sorption properties.
In the current study water sorption and glass transition behavior of freeze-dried sucrose,
mannitol, and maltose samples with varying BSA concentrations were investigated at
25 °C. BSA had an anti-plasticizing affect on the lyophilized maltose and sucrose
formulations. The pure maltose sample showed a glass transition at 50% relative humidity
(RH). As the BSA content was increased from 11% to 33%, the Tg increased from 57%
RH to 79.5% RH. Similarly, pure sucrose exhibited a Tg at 37%RH, while a 33%
BSA-sucrose mixture had a glass transition above 55% RH. Further, the BSA showed a
stabilization effect on sucrose structure collapse. Pure lyophilized sucrose crystallized at
55% RH, while the 33% BSA-sucrose formulation crystallized above 90% RH. Increasing
BSA content in BSA-mannitol samples allowed the formation of higher mannitol
amorphous contents.
P2
326
SURFACE MODIFIED SOLID LIPID NANOPARTICLES
Meike Harms, Martin A. Schubert, Christel C. Müller-Goymann,
TU Braunschweig, Institute for pharmaceutical Technology, Mendelssohnstr.
1, 38106 Braunschweig, Germany;
C.Mueller-Goymann@tu-braunschweig.de;
Meike.Harms@tu-braunschweig.de
In this study solid lipid nanoparticles (SLN) are prepared from mixtures of triglycerides
and the amphiphilic lipid lecithin. For the production of SLN high pressure
homogenization at temperatures above the melting point is employed. During
homogenization an emulsion is formed. This can result in an rearrangement of lecithin into
the aqueous phase in order to form micelles or liposomes. Furthermore lecithin can
stabilize the surface of the lipophilic droplets or stay within the lipophilic phase. SAXS and
TEM showed that no leakage of lecithin into the aqueous phase took place during
preparation. Furthermore NMR and DLS were performed to obtain information about the
chemical environment and mobility of the lecithin molecules. The incorporation of lecithin
into the lipid matrix (up to 30%) resulted in a decrease of the particle size of the SLN.
Further increase of the lecithin content (up to 50%) did not change the particle size. NMR
measurements showed a rather low mobility of the lecithin molecules up to a concentration
of 30% within the LM. Contents up to 50% led to a significant increase of the mobility.
From these results a model of surface modified SLN can be deduced. The particles consist
of a triglyceride enriched core, which is covered by lecithin – depending on the content
either as a monomolecular or multimolecular layer. The nonionic emulsifier is
incorporated into that layer.
245
Poster Abstracts
P2
327
HYBRID MICROGEL PARTICLES WITH ZINC SULPHIDE INCLUSIONS
Jessica Hain, Andrij Pich, Hans-Juergen P. Adler, Institute of Macromolecular
Chemistry and Textile Chemistry, Dresden University of Technology,
Mommsenstraße 4, 01069 Dresden, Germany;
jessica.hain@chemie.tu-dresden de
We report on the preparation of hybrid microgels filled with ZnS inclusions.
Temperature-sensitive poly-(N-vinylcaprolactam)-co-poly-(acetoacetoxyethyl
methacrylate) (PVCL/PAAEM) microgel particles have been used as reaction containers
for preparation and deposition of ZnS nanoparticles by reaction of zinc acetate and
thioacetamide under ultrasonic agitation. Zinc sulphide was directly deposited into the
microgel leading to formation of composite particles which exhibit colloidal stability and
temperature-sensitive properties. Dynamic Light Scattering measurements show an
interesting influence of incorporated ZnS on the particle size and position of the phase
transition temperature. Electrophoretic mobility measurements and microscopic
investigations with SEM, TEM and AFM were performed to determine the structure of the
generated hybrid microgel particles and their stabilization. Composite particles contain up
to 20 wt.-% of zinc sulphide and lose their colloidal stability with increasing inorganic
filler content. Obtained hybrid microgels exhibit the ability to form organized arrays on
different substrates during drying. This self organization process can be easily controlled
by adjusting the temperature or the pH-value. This interesting feature can be used for
preparation of patterned surfaces on nano-scale and is useful for numerous applications in
catalysis, electronics and material engineering.
P2
328
EXPLOITING EMERGING TECHNIQUES IN IMPRINT LITHOGRAPHY
TO MAKE HIGHLY UNIFORM, SHAPE-SPECIFIC DRUGS, IMAGING
AGENTS, AND NANO-CARRIERS
Larken E. Euliss, Julie A. Dupont, Christopher M. Welch, Benjamin W.
Maynor, Stephanie E. Gratton, Jason P. Rolland, Ginger M. Denison, Ashish
A. Pandya, Rudolph L. Juliano, Klaus M. Hahn, and Joseph M. DeSimone
University of North Carolina at Chapel Hill, Department of Chemistry, CB
#3290, Venable and Kenan Laboratories, Chapel Hill, NC 27599;
desimone@unc.edu
One of the current trends in the delivery of therapeutic, detection and imaging agents for
the diagnosis and treatment of cancer patients is the utilize nano-carriers such as
liposomes, micelles, dendrimers, biomolecules, polymer particles, and colloidal
precipitates. While these materials afford some control over load ability and structure,
each suffers from serious drawbacks with regard to stability, flexibility, polydispersity, or
functionality. Considerable effort has been devoted to the design and fabrication of these
materials, but it is clear that the scientific community has only “scratched the surface” with
respect to nanostructure complexity, composition, and function. For these reasons, we are
interested in developing a process that will allow the rigorous control over particle size,
246
Poster Abstracts
shape, composition, cargo, and chemical structure. Taking this all into account, we have
developed a new method of particle fabrication by borrowing the materials useful for
imprint lithography—an emerging technology adapted from the microelectronics
industry—in that we have a method that is extremely versatile and flexible for the direct
fabrication and harvesting of monodisperse, shape-specific nano-biomaterials. By
utilizing the method we have designed referred to as Particle Replication In Non-wetting
Templates, or PRINT, we have fabricated monodisperse particles with simultaneous
control over structure (i.e. varying aspect ratios, varying size regimes, composition) and
function (i.e. cargo, surface structure). We have accomplished this by utilizing
low-surface energy, chemically-resistant fluoropolymers as molding materials and
patterned substrates to produce these designer materials. Unlike other particle fabrication
techniques, PRINT is delicate and general enough to be compatible with a variety of
important next-generation cancer therapeutic, detection and imaging agents, including
various cargos (e.g. DNA, proteins, chemotherapy drugs, biosensor dyes, radio-markers,
contrast agents), targeting ligands (e.g. antibodies, cell targeting peptides) and functional
matrix materials.
P2
329
DEVELOPMENT AND CHARACTERIZATION OF INTERACTIVE
MIXTURES WITH A FINE PARTICULATE, MUCOADHESIVE CARRIER
FOR NASAL DRUG DELIVERY
Nelly Fransén, Erik Björk and Christer Nyström. Department of Pharmacy,
Uppsala University, Sweden; nelly.fransen@farmaci.uu.se
A new way of producing mucoadhesive delivery systems for nasal administration is
suggested by the creation of interactive mixtures with a small-size carrier particle.
Interactive mixtures are created by dry mixing a fine particulate substance with coarse
carrier particles. This results in a very homogenous mixture through deposition of the
smaller particles on the surface of the carriers. Most interactive mixtures have previously
been created with a carrier particle size exceeding 100-200 µm; this study shows that it is
possible to use a mucoadhesive carrier as small as 30 µm, which is well suited for nasal
administration. Sodium starch glycolate (SSG), which is commonly used as a
superdisintegrant in tablets, was used as carrier material because of its swelling capacity
and good flowability. SSG was fractioned into 4 size ranges to evaluate the effect of carrier
particle size on the mixture quality. Furthermore, mixtures with 4 different weight
percentages of the micronized model substance (sodium salicylate, SS) were prepared and
interactive mixtures could be obtained with as much as 4 % SS, corresponding to 20 %
surface coverage. However, this limit will most likely be substance specific. The emphasis
of the study was laid on mixture homogeneity evaluation and the experimental results were
compared with Pharmacopoeia regulations and theoretical calculations for an interactive
system with a small-size carrier. It was concluded that it is not possible to distinguish
between an interactive and a randomised mixture by sample analysis: the small particle
size does theoretically and practically give very homogeneous samples regardless of the
mixture quality. Visual inspection by scanning electron micrographs is therefore required.
The presented method does, in its simplicity, offer advantages compared with
247
Poster Abstracts
microparticles, since no dissolution step is necessary in the production and the surface
deposition of the drug could lead to a faster onset of effect.
P2
330
MONODISPERSE MICROGEL SYNTHESIS INSIDE MICROFLUIDIC
DEVICES
Bruno G. De Geest, Jo Demeester, Stefaan C. De Smedt, Laboratory of
General Biochemistry and Physical Pharmacy, Department of Pharmaceutics,
Ghent University,Harelbekestraat 72, 9000 Ghent, Belgium; and John Paul
Urbanski, Todd Thorsen, Department of Mechanical Engineering,
Massachusetts Institute of Technology, Mass. Ave. 72, Cambridge, MA 02139,
USA. br.degeest@ugent.be
Hydrophilic microgels have gathered large interest in biomedical field due to their
biocompatibility and the possibility to make them stimuli responsive by incorporation of
functional groups such as pH, temperature, electric field, glucose, etc responsive moieties.
However, there is no general method available for the synthesis of monodisperse
microgels, although this should offer considerable advantages compared to polydisperse
ones with respect to monitoring, predicting and modelling of their behaviour. In this poster
we demonstrate the fabrication of biodegradable monodisperse microgels inside a
soft-lithography based microfluidic device. The polymer used in this study is
dextran-hydroxyethyl methacrylate (dex-HEMA), this polymer has a Mw~19kDa and is
biodegradable by hydrolysis of the carbonate esters connecting the methacrylate groups
with the polymer backbone. An in-line droplet generator is used for the formation of
water-in-oil emulsion droplets wherein the water phase is a 30% solution of dex-HEMA.
Afterwards the dex-HEMA is polymerized by UV-irradiation yielding microgels with a
diameter of 10 µm.
P2
331
MODIFIED NANO-BENTONITE ANTI-VIRAL ACTIVITY AGAINST
THE HERPES SIMPLES VIRUS TYPE 1, RHINOVIRUS TYPE 37, AND
ROTOVIRUS
Jerald W. Darlington, Amcol International, Inc., 1500 West Shure Drive,
Arlington Heights, IL 60004, USA: jerry.darlington@amcol.com
Bentonite, the commercial name for montmorillonite, is the active mineral derived from
weathered volcanic ash. It has the unusual properties of a platelet structure with extremely
large surface area and an inherent negative charge in the platelet. One especially
interesting feature of the clay is the surface of the platelet can be chemically modified to
enhance the clay’s ability to absorb and bind toxins, poisons etc. Previous presentations
have reported the results of modifications of the clay against the Influenza Virus (H3N2
and H5N1) and Human Immunodeficiency Virus (HIV-1IIIB), The previous summary was
that modified clay R-0088 (0.01% w/v) exhibited reductions in infectivity of >90% and
>99% for H3N2 Influenza and HIV-1IIIB viruses respectively. Modified clays R-100,
248
Poster Abstracts
R-101 and R-102 all exhibited between 80% (0.0001% w/v) and >99% (0.01% w/v)
reductions in infectivity for Influenza H3N2 Virus. The current studies investigated
modified nano-bentonites against the Herpes Simplex Virus (Type 1), the Rhinovirus
(Type 37), and the Rotovirus. Each modification was incubated with the viruses for
different times and at different concentrations. Modified clays R-0402 exhibited reductions
in infectivity between 80% and 99.9% for Herpes Simples Type 1 and Rhinovirus Type 37.
Modified clays R-400 and R-402 exhibited between 90% and 99.9% reductions in
infectivity for Rotovirus. The results suggest that different modifications to the bentonite
clay alter the efficacy of the clay’s antiviral properties. It is very interesting to note that in
multiple cases, the same modified clay had antiviral properties against two or more very
different viruses. The potential uses of modified bentonite clay in the treatment and
prevention of Influenza, HIV, Herpes Simplex, Rotovirus and Rhinovirus infections are
significant. The current uses of bentonite clay for internal health benefit use as a
formulation aid in oral suspensions are indicative of the minerals extensive use by humans.
As an antiviral, the clay could be utilised for topical applications (i.e. vaginal gels for
protection against HIV infection and nasal sprays for treatment of Influenza infections) and
food supplements for humans (i.e. treatment against diarrhoea-causing enteric pathogens
such as rotaviruses) and animals (i.e. treatment against avian Influenza bovine shipping
fever).
P2
332
NOVEL CROSSLINKED CHITOSAN AND DEXTRAN GELS AS DRUG
DELIVERY SYSTEMS
José F. Almeida1,2, Armando Alcobia3, António Lopes2, Maria H. Gil1; 1Dept.
Eng. Química - FCTUC, P-3030-290 Coimbra, Portugal; 2Inst. Tecnol.
Química e Biológica - UNL, P-2781-901 Oeiras, Portugal; 3Hosp. Garcia Orta,
P-2801-951 Almada, Portugal; falmeida@itqb.unl.pt
Controlled release from biocompatible materials has received recently much attention for
its biomedical applications. Due to their biocompatibility and biodegradability,
gluocopyranosides such as chitosan and dextran appears as promising polymer materials if
one is able to regulate their rheological properties and the encapsulation/release efficiency.
In this work we prepared graft polymer gel particles from chitosan (“medium” Mw) and
dextran (Mw=5-40×106). The starting polymers were dissolved in the approprite aqueous
media (simple water for dextran, and 5% acetic acid for chitosan) in the suitable
semi-dilute concentration range (1-4% w/v) and as graft polymer we used
N-isopropylacrylamide (NIPAAm). The reaction was initiated either using γ radiation or
ammoniumcerium (IV)–nitrate radical initiator and as far as the gel rheology γ radiation
gives more consistent gel particles. FT-IR data for the grafted Dex-NIPAAm systems
revealed the presence of two peaks around ~1650 and ~1550 cm-1 which can be ascertained
with the typical amide I and II bands of NIPAAm, revealing the success of the grafting
reaction; this was also confirmed by 1H-NMR. As model drug we used a potent antiemetic
substance used in the prevention of chemotherapy-induced nausea and vomiting,
ondansetron, (±) 1, 2, 3,
9-tetrahydro-9-methyl-3-[(2-methyl-1H-imidazol-1-yl)methyl]-4H-carbazol-4-one
249
Poster Abstracts
(hydrochloride form) which was incorporated in the gel particles both before and after the
co-polymerization. Swelling capacity and cycles of incorporation/release of the drug were
evaluated with essays where PBS solution’s pH and temperature were varied in the
physiological range of interest (withdrawing of aliquots and HPLC analysis). Results
showed that, irrespective of the polymers, there is a positive correlation between
co-polymer concentration and swelling, as well as with drug incorporation. Release essays
show an initial burst followed by slow release but no significant pH dependence (in the
range of interest) and a moderate dependence with temperature.
P2
333
SILICA NANOPARTICLE FORMATION IN CONFINED
ENVIRONMENTS VIA BIOMIMETIC CATALYSIS
Christina A. Bauer, David Robinson, Darryl Y. Sasaki, Blake A. Simmons
Sandia National Laboratories, Livermore, CA 94551-0969;
cbauer@sandia.gov
In nature, silica formation occurs under ambient conditions with unprecedented control.
This is performed with templating biomolecules via morphosynthesis, wherein the starting
materials are spatially confined. In the case of diatoms, a set of cationic polypeptides
(“silaffins”) and polyamines were found to promote and mediate silica patterning. The
development of emulsions and micelles of a polyamine-containing organic phase are
thought to direct the intricate structures. We have explored the use of reverse micelles for
patterning, including scenarios whereby the amine is incorporated into a constrained
environment or where the amine is present as a functionality on the headgroup. In reverse
micelles, the resulting particles display smooth structures formed via aggregation of
smaller particles, reminiscent of diatoms. Reaction conditions within micelles were found
to differ from the bulk. Silica polymerization was monitored by a variety of methods,
namely fluorophore uptake, dynamic light scattering (DLS), and scanning electron
microscopy (SEM). After calcination, these samples reveal a high degree of porosity,
supporting incorporation of amines within the final structure. Vesicles were also explored
as confined reaction vessels and templates, whereby amines were included in the lipid head
group or as a polyamine incorporated into the bilayer surface.
P2
334
NANOPARTICLE-POLYMER COMPLEXATION: ELECTROSTATIC
SELF-ASSEMBLY AS A ROUTE TO STABLE DISPERSIONS OF
HYBRID NANOCOLLOIDS
A. Sehgal, Y. Lalatonne, M. Morvan, Complex Fluids Laboratory, CNRS Cranbury Research Center Rhodia Inc., 350 George Patterson Blvd., Bristol,
PA 19007 USA and J.-F. Berret, Matière et Systèmes Complexes, UMR
CNRS n° 7057, Université Denis Diderot Paris-VII, 140 rue de Lourmel 75015 Paris – France ; jean-francois.berret@ccr.jussieu.fr
The inherent instability of inorganic nanoparticle sols may be resolved by complexation
250
Poster Abstracts
with ion containing polymers at the particle interface. We exploit a
precipitation-redispersion (P-R) mechanism for complexation of short chain
polyelectrolytes with cerium oxide nanoparticles to extend their stability over a wide pH
range. Small angle X-ray scattering in conjunction with static and dynamic light scattering
reveals that P-R may yield hybrid nanocolloidal complexes with a singlet inorganic core charged corona structure. The electrostatic self-assembly of ionic stickers anchors the
chains onto the surface resulting in a polymeric brush which provides steric and
electrostatic stabilization. This simple strategy to achieve stable dispersions surmounts the
critical limitation in the use of nanoparticles, allowing a facile means to translate the
intrinsic properties of mineral oxide nanoparticles to a range of novel applications.
P2
335
ONE-STEP SYNTHESIS OF SPINEL IRON OXIDE-BASED
CORE-CORONA NANOPARTICLES FOR IN VIVO APPLICATIONS
Julien Reboul, Franck Bertorelle, Corine Gérardin, Laboratoire de Matériaux
Catalytiques et Catalyse en Chimie Organique UMR 5618 CNRS/Ecole de
Chimie Montpellier/UM1Institut Gerhardt FR187, 8 rue de l'Ecole Normale,
34296 Montpellier cedex 5, France ; Corinne Chanéac, Laboratoire de Chimie
de la Matière Condensée, Université Pierre et Marie Curie, 75252 Paris cedex,
Etienne Duguet, Institut de Chimie de la Matière Condensée de Bordeaux
UPR CNRS 9048, University of Bordeaux, 87 ave Dr Schweitzer, 33608
Pessac Cedex, France ; duguet@icmcb-bordeaux.cnrs.fr
Core-corona nanoparticles made of iron oxide cores and hydrophilic macromolecules are
of particular in vivo interest as MRI contrast agents or as hyperthermia mediators.
The main objective of the present study was to develop a new chemical route for the
synthesis of magnetic nanoparticles sterically stabilized in physiological medium and
capable of circulating for a long time in the blood compartment. An original one-step
aqueous synthesis based on the mineralization of hybrid supramolecular complexes
composed of iron salts and double hydrophilic block copolymers was investigated. The
polymers based-complex aggregates are obtained by complexation of Fe(2+) and Fe(3+)
ions by block copolymers, which contain a complexing block (such as sodium
polyacrylate) and a stabilizing block such as (polyethylene oxide, or polyacrylamide). The
present complex aggregates are precursor colloids which play the role of nanoreactors in
the preparation of the stabilized magnetite particles. Hydrolysis of the metal cations in the
aggregates leads to the formation of spinel iron oxide–based colloids, which are stabilized
by the block copolymers. Highly stable core-corona colloids could then be prepared. The
stability towards the addition of monovalent salts was found to be excellent. The polymer
neutral blocks, which form the diffuse corona of the particles, act as steric stabilizing
agents and are expected to act as plasma protein repellents. Moreover, the size of the hairy
magnetic nanoparticles was tuned by adjusting the copolymer-to-metal ratio, and the
polymer block lengths. Magnetic measurements allowed checking their superparamagnetic
behavior. Moreover, preliminary experiments showed promising results either as MRI
contrast agents or as heat promoters.
251
Poster Abstracts
P2
336
FABRICATION AND CHARACTERIZATION OF SiO2 AND MgO
COATED Fe2O3 NANOPARTICLES FOR HYPERTHERMIA
APPLICATIONS
Ji-Hun Yu, Powder Materials Research Center, Korea Institute of Machinery
and Materials, 66 Sangnam, Changwon, 641-011, South Korea; Yong-Ho
Choa, Jai-Sung Lee, School of Materials and Chemical Engineering, Hanyang
University, Ansan, 426-791, South Korea; and Heinrich Hofmann, Department
of Materials Engineering, Swiss Federal Institute of Technology (EPFL),
Lausanne, CH-1015, Switzerland; jhyu01@kmail.kimm.re.kr
SiO2 and MgO coated γ-Fe2O3 nanoparticles have been synthesized by chemical vapor
condensation and ultrasonic pyrolysis processes and their feasible possibilities on
hyperthermic application were investigated in this study. The synthesized γ-Fe2O3
nanoparticles have a spherical shape and around 20 nm in size. And SiO2 and MgO oxide
layers well coated on the surface of γ-Fe2O3 nanoparticles with around 5 nm in thickness.
The chemical compositions of the nanoparticles were 10wt% γ-Fe2O3 in SiO2 coated and
MgO coated γ-Fe2O3 nanoparticles. The generated heats from the composite particles
under alternative magnetic field were measured and SAR value, specific powder loss of the
composite particles, were calculated from the generated heats. The power loss of SiO2 and
MgO coated γ-Fe2O3 nanoparticles which means the magnetic heating effect under
alternative magnetic filed were much higher than the single phase γ-Fe2O3 nanoparticle due
the very fine size under 20 nm and well dispersion in body compatible SiO2 matrix.
Additionally, MgO coated γ-Fe2O3 nanoparticle has much higher powder loss value due to
the higher thermal conductivity of MgO than SiO2 coating layer. The superparamagnetism
and hyperthermic property of SiO2 and MgO coated γ-Fe2O3 nanoparticles were discussed
in terms of microstructural development in this study.
P2
337
PREPARATION OF GOLD NANOCOMPOSITES WITH DIELECTRIC
MAGNETIC CORES FOR TARGETTED PHOTOTHERMAL THERAPHY
Sang E. Park, Min Y. Park, Sang W. Lee, Dept. of Chemical and Bio Engineering,
Kyungwon University, Bokjeoung-dong San 65, Soojeoung-gu, Gyeonggi-do
461-701, Korea; and Jae W. Lee, Jea M. Yang, Seung J. Haam, Dept. of Chemical
Engineering, Yonsei University, Seoul 120-749, Korea; and Yong M. Huh, Dept. of
Radiology, Yonsei University, Seoul 120-749, Korea; upsilver60@kyungwon.ac.kr
Metal nanoshells are a new type of nanoparticles consisting of a dielectric core covered by a thin
metallic shell. In particular, gold nanoshell possesses unique biocompatible and optical proeprties
for targetted drug delivery and plasmonically-modualetd applications. Magnetic nanoparticles
have widely been used for biomedical imaging and cancer therapy of hyperthermia under
magnetic field. Thus, hybrid magnetic cores covered by thin metallic shell can be a potential
candidate for photothermal cancer therapy under magnetic resonance guidance. In this study,
252
Poster Abstracts
gold nanocomposites with magnetic cores were fabricated by the three consequtive steps: i)
synthesis of nano-scaled superparamagnetic iron oxide, ii) formation of spherical dielectic cores
embeded by magnetites, and iii) the growth of thin gold shell over the spherical cores. Gold
nanocomposites exhibited a strong NIR absorption at 800-1200 nm by adjusting the core/shell
ratio. The higher concentration of organometallic precursor and reducing agents induced the
stronger intensity of NIR absorption. However, the excessive addition of both chemicals
consequently led to the broadening and lowering of maximum absorption peak, probably due to
the flocculation of the hybrid nanoshells. The zeta potential and optical properties were
characterized by ELS (Electrophoretic Light Scattering System) and UV-Vis spectroscopy. The
surface morphology and size distribution were also characterized by TEM/SEM (Transmission/
Scanning Electron Microscopy), DLS (Dynamic Laser Scattering System), and FIB (Focused Ion
Beam).
P2
338
DNA-TEMPLATED SELF-ASSEMBLY OF TWO DIMENSIONAL AND
PERIODICAL GOLD NANOPARTICLE ARRAYS
Jaswinder Sharma, Rahul Chhabra, Yan Liu, Yonggang Ke, and Hao Yan*,
Department of Chemistry and Biochemistry and Biodesign Institute, Arizona
State University, Tempe, AZ 85287, USA; Jaswinder.Sharma@asu.edu
Nanoparticles (NPs) are being actively developed as building blocks for electronic,
photonic and spintronics devices. When they are organized into well-defined ensembles,
their collective properties depend critically on the inter-particle spacings and their
hierarchical organization. Up to now, methods to control these parameters are scarce.
DNA-templated self-assembly provides a unique solution to meet the above challenge, due
largely to the following features of DNA and DNA-based nanostructures: DNA has
well-defined geometry and most predictable, diverse and programmable
intra/inter-molecular interactions; DNA can be modified by different chemical groups,
which act as linkers to covalently attach DNA oligomers to the NPs; the design of stiff
DNA-based nanostructures and their self-assembly have become a routine method to
construct one- and two-dimensional DNA lattices of well-defined patterns. More
specifically, when NPs are assembled onto self-assembled DNA lattices, the periodicities
and interparticle spacings defined by the DNA scaffolds can be readily adjustable, with
nanometer spatial precisions. This level of precision provides exquisite control in the
construction of rationally defined NP architectures. Here we report the first time assembly
of 5 nm Au NP functionalized with a single DNA strand on three different patterned
structural templates that are constructed from self-assembled DNA tiles. We show that the
periodicity and interparticle spacings of the NP nanoarrays can be precisely controlled by
varying the DNA tile dimensions. In our strategy, the NP-conjugated strand first
participates in the formation of a single DNA tile structure, this Au NP-bearing DNA tile
was subsequently used to assemble with another DNA tile to form three different lattice
structures, each with a well defined periodical pattern. This novel system is amenable both
to the DNA lattice formation and preventing non-specific aggregations between the Au
NPs. This development paves the way to assemble more complex nanoparticle arrays on
DNA nanoscaffolds for future device applications.
253
Poster Abstracts
P2
339
DETECTION OF HYBRIDIZATION REACTIONS ON
MICROPARTICLES BY TEMPLATE DEPENDENT EXTENSION
Sofia Martins, Miguel Prazeres, Luis Fonseca, Gabriel Monteiro, Instituto
Superior Técnico, Av. Rovisco Pais, 1049-001 Lisbon, Portugal;
sofiamartins@mail.ist.utl.pt
Manufacturers of plasmid DNA (pDNA) intended for gene therapy or DNA vaccination
are required to comply with a set of rules established by regulatory authorities (e.g. FDA,
EUDRA). For instances, in order to get their products approval, the content of genomic
DNA (gDNA) from the producing cells must be below 10 ng/µg pDNA. Nucleic acid
hybridization is the current established technique used to quantify gDNA in
biopharmaceuticals. Microarray technology is a promising approach as it can provide the
sequence specific information in a faster and simpler way. However, one of the major
disadvantages of the miniaturized based hybridization reactions is the requirement for
target labeling. This is time consuming and it can change the levels of targets originally
present in the sample. In this work, we used a variation of primer extension reactions
performed in CPG-microparticles in order to detect and quantify gDNA present in pure
plasmid DNA preparations. A 20 nt oligonucleotide probe, complementary to the
Escherichia coli 16S rRNA gene, is immobilized via the 5’ terminus by thiol chemistry.
Microparticles are hybridized with complementary gDNA or plasmid DNA molecules for
negative control. The hybrids are then detected by template mediated extension of the
immobilized probe, at the sites where hybridization has occurred. The incorporation of
Digoxigenin-labeled nucleotides or fluorescinated nucleotides enables the detection of the
extended hybrids. Using this approach it was possible to directly quantify gDNA at
nanogram level. Hybridization with non complementary plasmid DNA molecules
produced no detectable signals. Therefore using this methodology it was possible to detect
nucleic acid’s hybridization reactions with high specificity without the need for a
pre-treatment of the target sample. The use of microparticles as the solid support for
immobilization offered several advantages, namely increased immobilization efficiency
and good hybridization kinetics in a miniaturized format.
P2
340
FORMATION OF HYBRID NANOPARTICLE-ALGINATE
MICROCAPSULES FOR BIO-DETECTION APPLICATIONS
Roberta Brayner, Stephanie Truong, Nordin Felidj and Fernand Fiévet,
Interfaces, Traitements, Organisation et Dynamique des Systèmes (ITODYS),
UMR-CNRS 7086, Université Paris 7-Denis Diderot, case 7090, 2 place
Jussieu, 75251 Paris Cedex 05, France; Thibaud Coradin and Jacques Livage,
Laboratoire de Chimie de la Matière Condensée, UMR-CNRS 7574,
Université Paris 6 - 4 place Jussieu, 75252 Paris Cedex 05, France ;
brayner@ccr.jussieu.fr
Natural polysaccharides such as chitosan, alginate and carragheenan have some important
properties such as mucoadhesivity, biocompatibility and nontoxicity, which render them
254
Poster Abstracts
interesting biomaterials. From a physicochemical point of view, these polysaccharides
have the special quality of gelling upon contact with cations (alginate and carragheenan)
and anions (chitosan) under very mild conditions. In this work, poly-saccharidic alginate
biopolymers have been used as templates for the controlled growth of several
nanoparticles. Au3+, Ni2+ and Co2+ could be used to form alginate gels as spherical
capsules. After reduction in mild conditions, metallic nanoparticles with narrow size
distribution were obtained inside alginate microcapsules Hybrid Au-alginate was then
immersed in methylene blue (MB) aqueous solution (used as a probe molecule) at a
concentration of 10-5M. It was observed a wavelength plasmon band shift probably due to
an electronic coupling between Au nanoparticles and MB molecule inside alginate
network. It was also observed an important SERRS effect for MB molecule adsorbed on
these Au nanoparticles compared to the same molecule adsorbed on a lithographycally
designed 2D Au arrays film. Metallic Ni, Co and NiCo solid solutions nanoparticles were
also obtained inside alginate matrix. In this case, SQUID measurements indicated that all
samples are ferromagnetic. In addition, hybrid Ni-alginate presents a superparagnetic
behavior with a blocking temperature TB = 290 K.
In summary, these polyfunctional hybrid materials may be applied in bio-detection, drug
delivery (because alginates have a great protein loading capacity), magnetic targeting or
magnetic resonance immaging.
Session P2
MAGNETIC nanoparticles LOADED ERYTHROCYTES AS MAGNETIC
RESONANCE IMAGING CONTRAST AGENT
Angelika Müller1, M. Brähler1, N. Buske2, R. Georgieva3, J. Pinkernelle1, U.
Teichgräber1, A. Voigt1, Hans Bäumler1, 1Charité - Universitätsmedizin Berlin,
D – 10098 Berlin, Germany, 2www.magneticfluids.de, 3Max-Planck Institute
of Colloids and Interfaces, D-14476 Golm/Potsdam, Germany;
hans.baeumler@charite.de
341
Superparamagnetic iron oxide nanoparticles (SPION, size 3-20nm) are often used in
magnetic resonance imaging (MRI), but their circulating half-life time of only two hours
and their fast phagocytosis by the lymphocyte-macrophage system makes them not ideal
for this indication. We encapsulated the SPIONs into Red Blood Cells (RBC). RBC can be
loaded with a variety of substances. They can be prepared to show similar in vivo survival
times as native RBC (120d). By loading the SPION into RBC, it is possible to circumvent
the lymphocyte-macrophage system and prevent fast accumulation of SPION in spleen and
liver. We used water based dispersions as loading agents, containing very well dispersed
citrate coated magnetite SPIONs (so called magnetic fluids, pH = 7.2, the counter ion was
potassium, content of Fe3O4 is 4vol.%, particle Ø 5-15 nm). For loading, the RBC´s
membrane was opened by hypoosmotic dilution and subsequently resealed. Magnetic RBC
(mRBC) show a strong attraction towards an external magnetic field gradient of a
permanent magnet. Transmission electron microscope pictures show the distribution of
SPIONs inside the cells and in the membrane. The relaxation time (Bruker minispec
contrast agent analyzer 1,5T) of mRBC in comparison to native RBC was reduced to
96,9% for T1 and 94,3% for T2. To show the effect of mRBC on images obtained by MRI,
255
Poster Abstracts
different dilutions of mRBC in whole blood were examined. Contrast enhancement
occured at dilutions of up to 1:20 (T2). A 10% dilution of mRBC in blood showed
significant contrast enhancement in phantoms of 1mm diameter (Bruker Pharm Scan 7T;
T2). 10% mRBC is the highest concentration of mRBC to be administered in vivo. With
single cell MRI (Signa excite 1,5T; T2*) individual mRBC could be distinguished.
P2
342
MAGNETIC NANOPARTICLES FOR POSSIBLE SIMULTANEOUS MR
IMAGING AND DRUG THERAPY OF BRAIN TUMORS
Beata Chertok, Bradford A. Moffat, Allan E. David and Victor C. Yang,
Department of Pharmaceutical Sciences, College of Pharmacy, University of
Michigan, Ann Arbor, USA; vcyang@umich.edu
This study intends to examine the plausibility of utilizing magnetic nanoparticles for
imaging and drug targeting of brain tumors. Magnetic nanoparticles consisting of an iron
oxide core and a starch shell were obtained from Chemicell® (Germany). The small
hydrodynamic diameter (~100 nm) suggested the possibility of their extravasation in the
tumor area through the EPR (enhanced permeability and retention) effect. High saturation
magnetization of 94 emu/gFe, determined by SQUID magnetometry, indicated that these
nanoparticles are highly responsive to the magnetic field. This magnetic responsiveness
lays the ground for possible retention of the nanoparticles within the brain tumor tissue by
application of an external magnetic field around the head, a strategy termed “magnetic
targeting”. Due to a high T2 relaxivity of 43 s-1mM-1, the presence of magnetic
nanoparticles at a particular spatial location in the brain manifests itself by reduction in the
local signal intensity on T2-weighted MR images in vivo, enabling the monitoring of the
distribution kinetics of these nanoparticles throughout the brain non-invasively.
MRI-based monitoring was used to test the effect of magnetic targeting on the extent and
selectivity of accumulation of the magnetic nanoparticles in the tumor of rats harboring
orthotopic 9L-gliomas. Animals were intravenously injected with nanoparticles
(12mgFe/kg b.w.) under application of a magnetic field of 0T (control) or 0.7T (test group)
around their head for 30 min. MR images were acquired before the administration of
nanoparticles and immediately after magnetic targeting at 1-hr intervals over a period of 4
hrs. Quantitative analysis of MR images revealed that magnetic targeting has resulted in a
significantly higher glioma accumulation of the nanoparticles in the test animals over the
control (p=0.005). Moreover, magnetic targeting also increased the target selectivity
index of nanoparticle accumulation in glioma over the unaffected normal brain (17±5 vs
1±0.5 in targeted vs non-targeted animals, respectively).
P2
343
HYDROGELS AND NANOPARTICLES IN MICROARRAYS FOR FOOD
CONTROL
Katarzyna Derwinska, Claudia Preininger, Ursula Sauer, ARC Seibersdorf
Research GmbH, 2444- Seibersdorf, Austria;
Katarzyna.Derwinska@arcs.ac.at
Microarrays have created new opportunities in medical, environmental and food
256
Poster Abstracts
diagnostics. To date the technologies are mainly restricted to the research lab due to their
high cost, lack of approved standards and certain technical hurdles, such as insufficent
reproducibility and sensitivity, especially in cases of low probe and target concentrations.
For achieving stronger signals and lower detection limits 3D hydrogels as well as
nanoparticles were employed as immobilization matrix for proteins. 3D hydrogels allow
extremely high immobilization capacities and low non-specific binding and furthermore,
provide an optimum water-like environment for proteins to maintain their structure and
thus, activity. On the contrary, immobilized particle arrays combine the advantages of
suspension (e.g. array element is prepared in bulk; variety of surface chemistries) and
planar arrays (e.g. high throughput), but are 6fold superior to suspension and 200fold
superior to planar arrays. Herein, we compare 3D hydrogel surfaces and particle arrays to
conventional 2D chip surfaces with respect to signal-to-noise ratio, detection limit and
suitability in food diagnostics. Seven commercial poly(urethanes) (PU) of different
swellability were tested both unmodified and modified with various additives (e.g.
methacrylate, chitosan) or various crosslinkers, such as hexamethylene diamine (HDA),
monochlortriazinyl-ß-cyclodextrin Na-salt (MCT) and cyanuric chloride (TsT). All
hydrogel surfaces were characterized by analytical methods, such as light microscopy,
AFM, profilometry, ellipsometry and contact angle measurements. ≥50 nm particles based
on melamin, polystyrene and silica were modified, coated to IgG and printed in hydrogel
solution providing multiple assay replicates. Both approaches were evaluated with regard
to signal-to-noise ratio, fluorescence background and data reliability (percentage of data
available for data anlysis, % CV, etc.) using a protein chip for detection of albumin in milk.
Detection limits below 0.01 mg/ml albumin were easily achieved demonstrating the
outstanding quality of the tested materials.
P2
344
PROTEIN MICROARRAYS AND ,SPATIALLY RESOLVED
PHOTOLUMINESCENCE IN BIO-CONJUGATED QUANTUM
DOT-PROBES FOR EARLY CANCER DETECTION
T. A. Zhukov, M . Dybiec, A. Zajac, W. Qian, C. Phelan, T. A. Sellers S.
Ostapenko,.H. Lee Moffitt Cancer Center & Research Institute; University of
South Florida, NNRC, 4202 E. Fowler Ave, 33620 Tampa, Florida,
mdybiec@eng.usf.edu
We propose a novel approach to increase the accuracy of early cancer detection through the
application of nanotechnology, where luminescent semiconductor quantum dots (QDs) are
conjugated with biomolecules. QD-bioconjugates offer unique opportunities of
simultaneous (multiplexed) detection and analysis of panel extremely low marker levels
and fluctuations. Quantitative measurement of biomarker on array can be achieved with
QD-immunometric methodology utilizing spatially resolved (mapping)
photoluminescence spectroscopy, and with confocal microscopy following with image
analysis. We have constructed QDs probes by conjugation with antibodies specific to the
selected lung, ovarian and prostate cancer serum and cell-based protein markers.
Preliminary data show that proposed methodology allows monitoring of changes in
biomarker concentration in nanoscale (pM-nM) range. We developed a prototype of a
257
Poster Abstracts
potential serologic assay with greater sensitivity than current methods and illustrate our
method with several serologic biomarkers for cancer – CA125, IL-10, PSA, VEGF. The PL
model in our study was developed to find and identify spectral signatures of
QD-bioconjugates. We observed that conjugated QDs are reliably detected at substantially
reduced concentration, which is critical for defining sensitivity limits of the luminescence
metrology in multiplex assay. In our microarrays we print antigene at different
concentrations on a functionalized substrate using MicroGrid microarrayer. Later
microarray is processed with conjugated QDs where detector antibody recognizes printed
antigene. We have modified the MicroGrid spotter to print Protein / Quantum Dots arrays
on silicon substrates. The processed microarray undergoes imaging with confocal
microscope and quantitation utilizing computerized dynamic analysis system (CDAS) for
classifying micro arrays to measure the features on array spots: such as area and intensity.
The quantitation of target antigen on the protein microarray spots show that the QDs
luminescence intensity tracks the antigene (biomarker) concentration in analyte sample.
Comparative analyses for sensitivity and specificity of biomarker detection with proposed
methodology and techniques in relation to cancer diagnoses are underway.
P2
345
PRODUCTION OF BIOCOMPATIBLE FILMS BY CONTROLLED
GAS-PHASE SYNTHESIS AND DEPOSITION OF NANOPARTICLES
Karsten Wegner1,2, Massimo Gatelli1, Simone Vinati1, Paolo Piseri3, Gero
Bongiorno3, Paolo Milani3
1) Tethis S.r.l., Piazzetta Bossi 4, I-20121 Milan, Italy;
2) Particle Technology Laboratory, Swiss Federal Institute of Technology,
ETH Zentrum ML F22, Sonneggstrasse 3, CH-8092 Zurich, Switzerland
3) CIMAINA and Dipartimento di Fisica, Università di Milano, Via Celoria 16,
I-20133 Milan, Italy; karsten.wegner@tethis-lab.com
An integrated process for controlled one-step production of nanostructured biocompatible
films was realized by combining gas-phase nanoparticle synthesis, aerodynamic particle
manipulation, size selection and deposition. The manufacturing process merges
high-temperature flame or plasma synthesis of nanoparticles and supersonic nozzle
expansion, thus benefiting from combined technological advantages: First, flame reactors
offer high level control over nanoparticle size, morphology, composition and crystallinity.
They are commonly used for industrial production of metal-oxide and carbon
nanoparticles. The employment of microplasma sources extends the spectrum of product
particles to non-oxide ceramics and metals. Second, expansion of the aerosol through a
system of nozzles and aerodynamic lenses allows gas-phase selection of a nanoparticle size
fraction and focusing of particles to a beam for defined-area deposition. Particle as well as
beam size can be controlled by the system pressure and the geometric arrangement of the
nozzles. Third, the process separates the deposition zone from the high temperature
( >1000°C) nanoparticle synthesis reactor, enabling coating even of temperature-sensitive
materials such as biodegradable polymers. Furthermore, integration of the technologies
yields high intensity nanoparticle beams. Coating of a 1000 cm2 surface with a 100 nm thin
258
Poster Abstracts
carbon film was demonstrated in less than 1 hour, even with a laboratory-scale apparatus.
Routes for scale-up and continuous production are being developed. The integrated
production technology for nanostructured thin films is presented by the example of
biocompatible titania films that are used for culturing primary human melanocytes. The
effect of process parameters in the different processing stages on nanoparticle and product
film properties is investigated. Furthermore, it is demonstrated how the use of masks
during deposition can even result in manufacturing of microarrays.
P2
346
SYNTHESIS OF MAGNETIC NANOPARTICLES BY THERMAL
DECOMPOSITION AND BIOCOMPATIBILITY
Sang Im Park, ChongOh Kim, Chungnam Nat`l Univ., Dept. of Mater. Sci.
and Eng., 220 Gung-dong, Yuseong-gu, Daejeon, Korea; and JongHwan Lim,
Chungnam Nat`l Univ., Div. of Veterinary Pharmacology and Toxicology; and
Nguyen Duy Ha, JongHee Kim, Chungnam Nat`l Univ., Research Center for
Advanced Magnetic Materials; sipark@cnu.ac.kr
Novel properties of nanoparticles arise from the large fraction of atoms, which reside on
the surface of the particles and from the finite number of atoms in core. Nanocrystals can
be synthesized in a number of different ways, including grinding, electrodeposition,
sputtering, metal evaporation, solution phase metal salt reduction, and neutral
organometallic precursor decomposition. Two of the most common procedures for high
quality nanoparticles are the thermal decomposition of a precursor molecule in the
presence of coordinating solvent and a capping ligand. Smart application of nanomagnetic
particles in biotechnology includes diagnosis and therapy as carrier to tumors. The
application of magnetic particles for biological parts requires the biological experiments
such as in vivo or in vitro certainly. In this work, the magnetic fluids with iron oxide that
had the spherical shape with uniform size were prepared, and the biocompatibilities of
them were investigated by using S. D. rat. Also, the surface of magnetic iron oxide was
radioisotope labeled, and the discharging routes of them were then tracked in a rat.
P2
347
GENE SILENCING OF MUTANT K-RAS MEDIATED BY POLYCATION
LIPOSOME
Tomohiro Asai, Satoshi Kido, Yuka Tsunoda, Kosuke Shimizu, Naoto Oku,
Univ. of Shizuoka, Dept. of Medical Biochem., Yada, Suruga-ku, Shizuoka
422-8526 Japan; and Takehisa Dewa, Mamoru Nango, Nagoya Inst. of Tech.,
Mater. Sci. and Eng., Gokiso-cho, Showa-ku, Nagoya, 466-8555, Japan;
asai@u-shizuoka-ken.ac.jp
Activating K-ras mutation is known as an ideal target for pancreatic cancer therapy, since a
point mutation in codon 12 of the K-ras oncogene occurs in about ninety percent of the
patients. RNA interference (RNAi) strategy for silencing mutant K-ras is promising
approach to treat pancreatic cancer. In this study, we developed cetyl-polyethylenimine
259
Poster Abstracts
(cetyl-PEI)-modified liposome (polycation liposome; PCL) for efficient delivering of short
interfering RNA (siRNA). PCL, composed of cetyl-PEI,
dioleoylphosphatidyl-ethanolamine (DOPE), and cholesterol, was prepared, sized, and
complexed with siRNA. Suit-2 human pancreatic carcinoma cell line with mutant K-ras
and HT-29 human colon adenocarcinoma with wild-type K-ras were used for evaluating
the effect of gene silencing. The results showed that PCL-mediated lipofection of mutant
K-ras siRNA reduced the protein expression and subsequent phosphorylation of
extracellular signal-regulated kinase (ERK) in Suit-2 cells. Furthermore, the knockdown of
mutant K-ras resulted in the suppression of Suit-2 cell proliferation. This suppressive effect
was significantly higher than the use of wild-type K-ras siRNA. In contrast, the silencing
effects of mutant K-ras siRNA in HT-29 cells were weaker than those of wild-type K-ras
siRNA. These results indicated that mutant K-ras siRNA/PCL system could specifically
work on the target mRNA. Next, we focused on mutant K-ras siRNA-induced apoptosis of
Suit-2 cells. Both DNA fragmentation assay and confocal microscopic study showed that
the lipofection of mutant K-ras siRNA resulted in induction of apoptosis. In confocal
microscopic observation, the number of TUNEL-positive cells was increased in mutant
K-ras siRNA compared with wild-type K-ras siRNA. These data suggested that mutant
K-ras siRNA could lead to apoptosis of Suit-2 cells by blocking mitogen-activated protein
kinase (MAPK) pathway. The finding indicated that mutant K-ras siRNA/PCL system
might be effective against pancreatic cancer.
P2
348
AMPEROMETRIC IMMUNOSENSOR BASED ON HIGHLY DISPERSED
GRAPHITE MICROPARTICLES FOR INFLUENZA VIRUSE DETECTION
Ravil A Sitdikov and Ebtisam S Wilkins, Department of Chemical and
Nuclear Engineering, University of New Mexico, Albuquerque, NM 87131;
sitdikov@umn.edu
Avian influenza is an infectious disease of birds caused by type A strains of the influenza
virus. Amperometric immunosensor for Parainfluenza (PI) Type I virus and Influenza virus
Type A (IA) detection and flow-through sandwich immunoassay scheme was developed .
Highly dispersed graphite microparticles offers a large surface area and at the same time
functions as the working electrode because of its good conductive nature. This provides the
basis for covalent immobilization of anti-influenza A or anti-parainfluenza goat antibodies
on the graphite particles and amperometric detection of peroxidase enzyme label. Such a
process enhances the proximity of biological components with the transducer, a very
essential factor for biosensor development. Electrochemical transduction offers certain
advantages with respect to ease of operation and sensitivity. The immunosorbent is
deposited on the filter membrane by vacuum resulting in dispersed graphite
immunosorbent forming the measuring immunoelectrode (disposable immunosensing
elements). Flow cell serves as an immunoreactor as well as an electrochemical cell. The
optimization of disposable immunosensing elements of the amperometric transducer is
based on the principle of close attachment of the components of the ligand-receptor system
to the electrode surface of the transducer. Lower detection limits for PI and IA assay are 0.5
and 0.4 ng/ml respectively with a coefficient of variation (CoV) of 0.05. The upper
260
Poster Abstracts
detection limit for PI is very high as 10,000 ng/ml. The total time of the assay is about 22
minutes. Described electrochemical biosensor can provide rapid, simple and low-cost
on-field detection. Electrochemical measurement protocols are also suitable for mass
fabrication of miniaturized devices.
P2
349
CHARACTERIZATION OF REP 2006 ANTIVIRAL DRUG AND DRUG
DELIVERY SYSTEM FOR SMALL ANIMAL MODELS
Divey Saini, Mark Buller, St. Louis University, Dept. of Molecular
Microbiology and Immunology, St. Louis, MO; Pratim Biswas, Washington
University in St Louis, Environment Engineering Science, St Louis, MO; and
Andrew Vaillant, REPLICor Inc., 500 Cartier Blvd West, Suite 135, Laval,
Quebec, Canada; sainid@slu.edu
Due to the mounting bioterrorism threats in recent years and the resulting heightened
security levels there is an urgent need to stockpile vaccines and antivirals for national
bio-defense. A step in this direction has been taken by REPLICor, which is developing a
broad-spectrum anti-viral drug to treat at least 12 families of viruses. The drug is in its
preclinical phase where it is being tested in small animal models through aerosol
inoculation. The drug was aerosolized using a Aero Mist Nebulizer and delivered to mice
by an eight-port nose-only aerosol chamber. Drug particle size and concentration was
measured with a Scanning Mobility Particle Sizer (SMPS 3081) and an Aerodynamic
Particle Sizer (Model 3321). The drug particle sizes were measured in the micron and
submicron size range with the relative amounts of each particle dependant on drug
concentration. For 0.1 mg/mL, 1 mg/mL, 10 mg,mL, and 100 mg/mL the geometric mean
diameters were 28.93 nm, 43.80 nm, 75.77 nm, and 107.33 nm, respectively. The particle
number concentrations for similar drug concentrations was measured to be 1.17e6, 2.49e6,
7.89e6, 2.88e7, and 3.29e7 particles/cc. The aerosol delivery chamber was characterizd as
a function of particle size and number concentration. The drug characterization parameters
were measured at the four ports of the chamber. For 10 mg/mL drug concentration the
percentage standard deviation in particle size and number concentration for the four ports
was 4.15% and 7.02 % respectively. This data suggests a consistant aerosol dose will be
delivered to the ports of the aerosol chamber at an optimum particle size for inhalation
studies with small animal models.
P2
350
A PRACTICAL APPROACH TO THE USE OF NANOPARTICLES FOR
VACCINE DELIVERY
Janet R. Wendorf, Manmohan Singh, Jina Kazzaz, Padma Malyala, Elawati
Soewanan, James Chesko, Mildred Ugozzoli, Derek T. O’Hagan, Novartis
Vaccines & Diagnostics; 4560 Horton Street, Emervyille, California, 94608,
janet_wendorf@chiron.com
Poly (DL-lactide-glycolide) (PLG) polymers were used to create nanoparticles ranging in
size from 110 nm to 230 nm. Protein antigens were adsorbed to the nanoparticles for a
261
Poster Abstracts
vaccine delivery system. The nanoparticles were compared to alum in vivo with a
recombinant menigococcal vaccine protein. The nanoparticles in comparison to alum were
found to have either enhanced or comparable immunogenicity. This makes the
nanoparticles an enticing candidate for a vaccine delivery system. Nanoparticles offer
advantages over microparticles with ease of processing and higher surface area for protein
adsorption. We found that proteins could be adsorbed to nanoparticles up to at least 5%
(wt. protein/wt. PLG) while microparticles plateaued at approximately 1.5% (wt.
protein/wt. PLG). However, nanoparticles do not resuspend to the same size post
lyophlization without the addition of excipients. Sugars and surfactants were investigated
as resuspension agents for nanoparticles. Vaccine compatible excipient combinations
were tested to find conditions where initial particle size was recovered. Sterile filtration of
smaller nanoparticles (<130 nm) led to minimal PLG losses and allowed the initial
nanoparticle preparation to be a non-aseptic process simplifying preparation in comparison
to microparticles. We found that the smaller nanoparticles of size 120 nm needed more
surfactant to resuspend than slightly larger (~220 nm) nanoparticles. To resuspend 120nm
nanoparticles formulations of poly (vinyl alcohol) with sucrose/mannitol or dioctyl sodium
sulfosuccinate (DSS) with trehalose/mannitol were sufficient. The protein-nanoparticle
resuspension with the same excipient combinations was also dependent on the protein and
protein loading level. A lyophilized nanoparticle formulation with adsorbed protein
antigen and minimal excipients is an effective vaccine delivery system.
P2
351
EVALUATION OF NANOENCAPSULATION PERFORMED BY SPRAY
DRYING TECHNIQUE FOR THE DELIVERY OF TUBERCULOSIS
DRUGS (ATD)
Hulda Shaidi Swai1*, K.T. Hillie2, N. Cingo3, L. Kalombo1, M. Legodi1, B.
Semete4, and L. Shoba4, 1Council of Industrial Scientific Research (CSIR)Polymer Ceramics and composites, P.O Box 395, Pretoria 0001, South Africa;
2
Council of Industrial Scientific Research (CSIR)- National Metrology
Laboratory, P.O Box 395, Pretoria 0001, South Africa; 3Departiment of
Chemistry, University of South Africa-UNISA, P.O Box 392 Pretoria 0003,
South Africa; 4Council of Industrial Scientific Research (CSIR)- BioSciences
P.O Box 395, Pretoria 0001, South Africa; hswai@csir.co.za
Tuberculosis (TB) is gaining ground: in 2001, the disease killed more people than any
previous year in history. Globally, there is a 3% increase in new TB cases each year, while
in Africa, the increase is 20% per year, largely due to co-infection with HIV/AIDS. Every
year, eight million people worldwide develop active TB and three million die from it, while
more than 400 000 new cases of multi-drug resistant TB (MDR-TB) are diagnosed.
Although an effective therapeutic regimen is available, patient non-compliance results in
treatment failure, while the emergence of drug resistance can lead to MDR-TB. Not a
single new class of TB drug has been developed in over 40 years. The TB nano drug
delivery study seeks to address patient non-compliance in TB control programmes through
the development of a system whereby drugs can be administered in a single dose that
maintains an active level (minimum inhibitory concentration – MIC) for a number days,
262
Poster Abstracts
weeks or months. This will be done by nano-encapsulating techniques with known TB
drugs, which have very poor bioavailability using an FDA approved biodegradable
polymer which will allow slow steady release of the drugs for longer periods. The present
work will focus on the encapsulation of the anti-tuberculosis drug (Isonaizid) into a
biodegradable polymer, Poly(lactide-co-glycolide (PLG) using spray drying technique.
These particles have been prepared in our lab and characterised via SEM, LLS, Zetasizer
and UV-Vis spectrophotometry. It is believed that the cellular uptake of the nanocarriers is
strongly dependent on their surface charge. Therefore to get positively charged
nanoparticles remains an additional target for this work. Chitosan, a positively charged
natural and biodegradable polymer will be used as a co-surfactant aside polyvinyl
alcohol-89% partially hydrolysed, with the aim of imparting a positive charge to the
nanoparticles. The process parameters of the spray drying i.e. temperatures, feeding rate
and airflow rate will be optimised in terms of high incorporation efficiency of the drug, size
and the morphology of the nanoparticles.
P2
352
DOUBLE CARRIER SYSTEMS AS NOVEL DRUG DELIVERY
VEHICLES
Edith C. Rojas, Nurettin Sahiner, Vijay T. John, Kyriakos D. Papadopoulos.
Department of Chemical and Biomolecular Engineering, Tulane University,
New Orleans, LA 70118, USA; erojas@tulane.edu;
pops@mailhost.tcs.tulane.edu
Cationic hydrogel particles were prepared as carriers in nano and micro size. It was shown
that these carriers can be transported by another micro-scale delivery vehicle such as an
oil-in-water (O/W) or a water-in-oil-in-water (W1/O/W2) emulsion system. The perception
is that the use of a carrier inside another carrier provides the advantage of both systems. For
example, while one carrier is keeping the load in perfect conditions i.e. stealth, the other
carrier can afford the storage and handling for the initial shipment. Furthermore, the
conjugated action of multiple emulsions and hydrogels can be designed to work
sequentially, which may be useful for achieving prolonged delivery of the active
substance, better-tuned release and/or higher-uptake efficiency. This system can also be
used as double delivery-vehicle, each carrier carrying specific loads. The microcapillary
technique developed in our laboratory was employed to closely monitor the individual
multiple emulsion systems. Here, the emulsion system consists of either nanohydrogels
dispersed in the internal aqueous phase (H/W1/O/W2), or microhydrogels themselves
suspended in the oil phase (H/O/W). Through such observations, the selective
active-substance release from the delivery vehicles was shown to be promoted by external
stimuli. Since fluorescent dye was used as a model active substance, fluorescence
microscopy images revealed that hydrogels (first carrier) prevent the fluorescent dye from
spontaneously migrating into the external aqueous phase of the second carrier. Then, the
fluorescent dye loaded into the hydrogels was shown to be released upon changing the pH
of the medium.
263
Poster Abstracts
P2
353
AN INVESTIGATION INTO USING SPRAY CHILLED GELUCIRE 50/13
MICROSPHERES AS CARRIERS FOR POORLY SOLUBLE DRUGS
Sheng Qi, Duncan Q.M. Craig, School of Chemical Sciences and Pharmacy,
University of East Anglia, Norwich NR4 7TJ, UK; and Delphine Marchaud,
Gattefossé SAS, 36 Chemin de Genas, BP 603-F-69804 Saint-Priest Cedex,
France; sheng.qi@uea.ac.uk
Spray chilled Gelucire 50/13 microspheres were used as drug carriers to improve the
solubility of poorly soluble drugs. This formulation combines the advantages of solid
dispersions and microparticulate dosage forms. It has the potential of not only improving
the bioavailability of poorly soluble drugs in vivo, but also of reducing the risks of single
dose formulations after administration. Piroxicam as the model drug was encapsulated in
the Gelucire 50/13 matrix using a customized spray-chilling apparatus. The microspheres
were determined to have a spherical shape with smooth surfaces and to be between 20μm
and 200μm in diameter. Thermal studies revealed that there was no interaction between
piroxicam and Gelucire 50/13 matrix. Hot stage microscopy (HSM) experiments in
polarized mode proved that the drug particles exist as separate crystals in the microspheres.
The dissolution behaviour of the microspheres in water was monitored using constant
temperature stage (37˚C) HSM. The microspheres were observed to swell and lose their
spherical shape on exposure to water. The dissolution results of the piroxicam loaded
microspheres showed significant improvement compared to those of drug alone. This is as
a result of improved wettability of the drug particles by using lipid materials with relatively
high HLB value. Particle size, drug loading, and aging of Gelucire 50/13 have been shown
as the main factors influencing the drug release from the microspheres. For microspheres
of size between 60-200μm in diameter, slower drug release was observed compared to
smaller microspheres. For particles in this size range (60-200µm) lower drug loading and a
longer aging period increased the dissolution rate. However, for the microspheres with size
below 60μm in diameter, the drug release rate did not vary with these factors. Further
investigation is required for a fuller understanding of the drug release mechanism of spray
chilled Gelucire 50/13 microspheres.
P2
354
LONG-TERM STUDY OF EPO-SECRETING MYOBLASTS ENTRAPPED
IN MICROCAPSULES ELABORATED WITH FIVE DIFFERENT
COMMERCIAL ALGINATES
Sara Ponce, Gorka Orive, Rosa Hernández, Alicia R. Gascón, Jose Luis
Pedraz, Laboratory of Pharmacy and Pharmaceutical Technology, University
of Basque Country, Vitoria, Spain; and Josep M. Canals, Jordi Alberch, Dept.
Cellular Biology and Pathologic Anatomy, Faculty of Medicine, IDIBAPS,
University of Barcelona, Spain; knbpomas@vc.ehu.es
The alginate is the most frequently employed anionic polysaccharide for cell
microencapsulation. However, to ensure the clinical application of this polymer, it is
critical to prove that the alginate has a suitable and reproducible biocompatibility. Since it
264
Poster Abstracts
has a natural origin, several contaminants exist in its composition. These contaminants are
in general mitogenic and inflammation provoking molecules which activate host’s immune
response provoking the release of cytokines such as IL-lβ, IFN-y, IL-6 and TNF-α. In the
present study, five different commercial alginates were used for the elaboration of
microcapsules. EPO-secreting C2C12 myoblasts from C3H mice were immobilized in the
different microcapsules in order to study the impact of the alginate properties (purification
degree, composition and viscosity) on the long-term efficacy of the therapeutic strategy.
Myoblasts were used since the experience has shown that murine C2C12 myoblast cell line
is particularly well suited for cell encapsulation technology. The elaborated microcapsules
were implanted subcutaneously in Balb/c mice. High and constant hematocrit levels were
maintained until day 130 after only one shot of the cell-loaded microcapsules and without
implementation of immunosuppressive protocols. According to the results, all types of
alginate microcapsules seemed to function in a similar manner increasing the hematocrit
level in the transplanted mice including the group of mice which received microcapsules
elaborated with a nonbiomedical grade LVM alginate, although the latter showed an
increased fibrotic overgrowth. The potential role of EPO effects and the impact of the
released EPO dose on these results are discussed in detail.
P2
355
IN VIVO FATE OF THE MICELLE FORMING BLOCK COPOLYMER
POLY (ETHYLENE GLYCOL-BLOCK-CAPROLACTONE) IN MICE
FOLLOWING INTRAVENOUS ADMINISTRATION
Jubo Liu, Faquan Zeng, Christine Allen*, Department of Pharmaceutical
Sciences, University of Toronto, 19 Russell street, Toronto, ON, Canada M5S
2S2; *cj.allen@utoronto.ca, jubo.liu@utoronto.ca
Poly (ethylene glycol)-b-poly (caprolactone) (PEG-b-PCL) copolymers were synthesized
and characterized in terms of their CMC, thermal properties, biocompatibility and
biodegradation profiles. The copolymers were employed to form micelles as potential
drug delivery carriers. The biologically relevant physico-chemical properties of these
micelle systems were investigated. The PEG5000-b-PCL5000 micelles were selected for
evaluation of in vivo fate following i.v. administration due to their small size, superior in
vitro stability and slow degradation profile. Specifically, 3H-labeled PEG5000-b-PCL5000
micelles with an average size of 56nm were i.v. administered to Balb/C mice at doses of
250mg/kg, 1.5mg/kg and 0.1mg/kg in order to examine the distribution kinetics of 1)
copolymer assembled as thermodynamically stable micelles (i.e. concentration of
copolymer above CMC prior to and upon dilution following i.v. administration), 2)
copolymer assembled as thermodynamically unstable micelles (i.e. concentration of
copolymer above CMC prior to but not following dilution upon i.v. administration) and 3)
copolymer single chains. The biodistribution of the copolymer in the major organs was
investigated and the main pharmacokinetic parameters were determined by fitting the data
into compartmental open models. In summary, the formation of micelles was found to
effectively entrap the copolymer in the plasma as revealed by the significant difference
between the distribution volume of micelles (i.e. 1.67mL and 1.49mL for doses of
250mg/kg and 2.5mg/kg, respectively) and copolymer single chains (i.e. 7.54mL). The
265
Poster Abstracts
moderate elimination half-life of the 1.5mg/kg (i.e. 16.7 hrs) dose group indicated a good
kinetic stability for this micelle system even though the copolymer concentration fell
below the CMC upon dilution following i.v. administration. The AUC values in all organs
examined from 0 to 48 hours were found to decrease in the following order liver > kidney>
spleen > lung > heart in all dose groups. The biodistribution profiles were found to be dose
dependent as indicated by the increase in the accumulation of copolymer single chains
compared to micelles in the kidney.
P2
356
TREHALOSE BEARING POLYMERIC PARTICLES: SORPTION
INDUCED HYDROLYTIC DEGRADATION OF PESTICIDES AND
CHEMICAL AGENTS
Yongwoo Lee, Ted, Mendum, Chunyong Wu, Nese Orbey, and John Puglia,
Foster-Miller, Inc., 195 Bear Hill Road, Waltham, MA 02451-1003, USA;
ylee@foster-miller.com
Cross-linked Polymeric Trehalose (PT) particles having trimeric alkyl spacers were
synthesized, sieved to achieve a narrow particle size distribution, and employed as a
physical support for enzyme catalysts. These particles were shown to be chemically inert
and robust enough to endure extended exposure to highly acidic and highly alkaline media.
Sequestration of methyl parathion (MPT) and its hydrolysis product p-nitrophenol (pNP)
in the macroporous cavities of these particles was confirmed. Organophosphorous
Hydrolase (OPH) was immobilized between molecular layers of non-covalently attached
buffered polyelectrolyte within the cavities of the particles, utilizing secondary interactions
such as ionic and/or hydrophobic interactions between molecular layers, rather than
covalent bonding. These environmentally benign, polymeric particles were demonstrated
to have high binding efficiency for the enzyme catalyst, high enzymatic activity, the
capability to efficiently hydrolyze and sequester their substrates, and the ability to act as
sorption-induced hydrolyzing vehicles against biological and chemical threat agents (GA,
VX).
P2
357
BIODEGRADABLE NANOPARTICLES FOR VACCINE DELIVERY
SYSTEMS
Ik Joong Kang and Bum Gil Kim, Department of Chemical and Bio
Engineering, Kyungwon University, Sungnam 461-701, KOREA ;
ijkang@kyungwon.ac.kr
Many biological researches have demonstrated that chitosan derivatives were effective,
safe absorption enhancers to improve the delivery efficiency of drug, and suitable for
controlled drug release because it has stability, bio-compatibility and biodegradability.
Recently, the interest in the extension of human life and the health has been increased.
Many researches in a pharmacy and a medical area have studied in a sustained drug release
property and stability of drug release property in a body. Hepatitis virus(Hv) is the liver
266
Poster Abstracts
affinity DNA virus as a kind of hepadna virus has 42 nm diameter and no cell
denaturalization phenomenon. Outer membrane of the virus consist of hepatitis surface
antigen(HBsAg) and center is composed of Hv DNA and hepatitis B core antigen
(HBcAg). It is very mortal that people over 8 % get infected with chronic hepatitis as
increasing trend and consequently leaded to the death because of a complication arises of
cirrhosis and liver cancer. All of the infants have to be prescribed by three consecutive
injection of hepatitis vaccine just after his birth adults are also prescribed by an intra
muscular injection every five years. In this study biodegradable polymer's derivatives was
synthesized and made to nanoparticles as a supporter of vaccine. The character of vaccine
delivery carrier as its size and surface polarity was analyzed by AFM, SEM, FT-IR, HPLC,
ELS, and Zeta potential for the development of effective drug delivery system. As a result,
biodegradable nanoparticles containing vaccine obtained the effectiveness in drug release
control the immunological reaction.
P2
358
EFFECTIVE STABILIZATION OF BIOACTIVE INGREDIENTS FOR
LONG-TERM STORAGE USING W/O/W ENCAPSULATION AND
BUFFERING LAYER
Jae-Eun Jung, Mi-Ok Jung, Jee-Hyun Ryu and Kyung-Do Suh
Department of Chemical Engineering, College of Engineering, Hanyang
University, Seoul 133-791, Republic of Korea; and Jin-Woong Kim, Division
of Engineering and Applied Sciences, Harvard University, Cambridge, MA
02138, USA; kdsuh@hanyang.ac.kr; flory81@hanmail.net
Beneficial materials for the human body such as enzyme or antioxidant have a drawback,
which is too weak from the environmental factors to preserve their bioactivity for a
long-term storage. For instance, papain which is an enzyme from a papaya fruit is
extremely sensitive to the heat. One of the antioxidants, riboflavin (Vitamin B2) is also
unstable in water phase especially in the sunlight. To overcome these problems, various
stabilization methods, containing W/O/W emulsion, encapsulation and suspension
polymerization, have been widely reported. However, complete solutions are not
suggested yet. In addition, water-soluble biomaterials are generally stabilized by W/O/W
evaporation method, but the initial drug loading ratio is 40% below. In this presentation,
we proposed an efficient stabilization method for bioactive ingredients by introducing a
buffering layer to the microcapsules. Papain and riboflavin are chosen as model drugs;
these were microencapsulated with polymethylmethacrylate (PMMA) using W/O/W
evaporation method. Various types of polyols, such as polypropylene glycol (PPG),
polyethylene glycol (PEG) and triblock polyol (PEG-PPG-PEG), were applied to buffering
layers. Because of the nature of polyols, it might be existed between the drug and polymer,
isolating the drug from the surrounding. The bioactivity of the capsules was measured as a
function of storage time, and the results were compared to the HLB values of polyols. The
existence of drugs in the capsules was confirmed using a confocal laser scattering
microscope (CLSM). For a clear analysis, the drugs and polyols labeled with fluorecien
isocyanate (FITC), and rhodamin B isocyanate (RBITC), respectively. Optical microscope
(OM) and scanning electron microscope (SEM) were used to observe the morphology of
267
Poster Abstracts
the microcapsules. The initial drug loading efficiency and the preservation of drugs in the
buffering layer incorporated microcapsule were determined by UV-vis spectroscope.
P2
359
DEVELOPMENT OF A NEW MULTIPARTICULATE SYSTEM FOR
COLON CONTROLLED DRUG DELIVERY
Elquio E. Oliveira, Acarília E. da Silva, Marcelo G. Silva, Toshiyuki N. Junior,
E Sócrates. T. Egito, Universidade Federal do Rio Grande do Norte,
Departamento de Farmácia, Laboratório de Sistemas Dispersos (LASID), Rua
Gal. Gustavo Cordeiro de Farias, s/n, 59010-180, Natal/RN, Brazil.
socrates@ufrnet.br ; and Anselmo G. Oliveira, UNESP-Araraquara, Rodovia
Araraquara-Jaú, km 01, 14.801-902 Araraquara-SP – Brazil
Nowadays delivery of poorly absorbed drugs in stomach and small bowel and prevention
of side effects caused by them in such sites have been particularly desirable. For those
purposes, colon specific drug delivery systems have been developed for treatment of colon
diseases like ulcerative colitis, Crohn’s disease and colon cancer. Those systems may be
obtained by microencapsulation employing biodegradable polymers such as xylan, which
is hydrolyzed by enzymes present in the colon, or pH-dependent polymers such as
Eudragit® S-100. The various approaches used for producing the microcapsules include
cross-linking reaction and spray drying technique. The aim of this study was to develop a
novel multiparticulate system based on xylan microcapsules coated with Eudragit® S-100.
The microcapsules were produced by the interfacial cross-linking process. An alkaline
solution containing xylan and NaOH 0.6N was emulsified in 30mL of the
chloroform:cyclohexane [1:4(v/v)] containing 5% (w/v) sorbitan triesterate. After 10 min, the
interfacial cross-linking reaction was trigued by adding 40 mL of 5% (w/v) terephthaloyl
chloride solution. The reaction was ended by dilution with 30 mL of cyclohexane.
Subsequently, microcapsules were separated by centrifugation and washed several times.
For the coating process using a spray dryer, the dispersion was prepared by using 150 mg
of xylan microcapsules and 400 mg of Eudragit® S-100 in 50 mL of water and stirring for
25 min. Aqueous suspension was spray-dried at 1.2mL/min (inlet temperature 120ºC)
using a Büchi Model 191 laboratory spray dryer using a 0.7 mm nozzle. The process
induces the formation of microcapsules. The optical and electronic microscopy (SEM)
revealed non-aggregated spherical microcapsules with a smooth surface showing a mean
particle size of 10.5 ± 0.1µm. Regarding the visual aspect, the sample appeared to be a fine
yellowish powder. This system represents an eligible colon-specific drug delivery system
using a multiparticulate model based on xylan microcapsules coated with an enteric
polymer.
P2
360
268
SODIUM DICLOFENAC INCORPORATION INTO XYLAN
MICROCAPSULES FOR COLONIC DRUG DELIVERY
Elquio E. Oliveira, Acarília E. da Silva, Marcelo G. Silva, Toshiyuki N. Junior,
E Sócrates. T. Egito, Universidade Federal do Rio Grande do Norte, Depto. de
Poster Abstracts
Farmácia, Laboratório de Sistemas Dispersos (LASID), Rua Gal. Gustavo C.
Farias, s/n, 59010-180, Natal/RN, Brazil. socrates@ufrnet.br; and Anselmo G.
Oliveira, UNESP-Araraquara, Rodovia Araraquara-Jaú, km 01, 14.801-902
Araraquara-SP – Brazil
Microparticles are drug delivery systems able to modify the drug action by changing its
bioavailability. Xylan, a polymer abundantly found in nature, is enzimatically degraded in
colonic environment in human body. Hence, it is an eligible material to produce colon
specific drug carriers. The aim of this study was to incorporate sodium diclofenac (SD) in
xylan microcapsules and evaluate the characteristics of both systems. The microcapsules
were prepared by the interfacial cross-linking process. The polymer solution was obtained
by dissolving 124 mg of xylan in 10mL of NaOH 0.6N. 6 mg of SD was added in 6mL of
polymeric solution and emulsified in 30mL of chloroform:cyclohexane [1:4(v/v)] containing
5% (w/v) sorbitan triesterate. After 10 minutes, the interfacial cross-linking reaction was
trigged by adding 40 mL of a 5% (w/v) terephthaloyl chloride solution in
chloroform:cyclohexane [1:4 (v/v)]. The reaction was ended by dilution with 30 mL of
cyclohexane. Then, the microcapsules were separated by centrifugation and washed
several times. At last, the microcapsules were characterized regarding their morphology,
homogeneity, pH and visual aspect. The drug loading efficiency was determined by
spectrophotometry at 275nm. Concerning the visual aspect, both free microcapsules (FM)
and sodium diclofenac microcapsules (SDM) were observed to be a yellowish dispersion.
Microscopy analysis showed that not only FM but also SDM were quite spherical in shape
and a little bit aggregated. They presented a mean diameter of nearly 25μm. The pH was
7.12 and 4.0 for FM and SDM, respectively. Such pH change is an indicative that
reinforces SD encapsulation. Altogether, the results demonstrated the feasibility of
producing xylan microcapsules with and without SD, both presenting the same aspect and
homogeneity. A high encapsulation efficiency rate of 81.33% was achieved. Therefore, it
may be concluded that SDM can be a new therapeutic carrier for the treatment of
inflammatory diseases.
P2
361
DRUG RELEASE FROM NANO-PARTICLES MADE OF
RADIATION-CROSSLINKED ELASTIN MODEL POLYPEPTIDES
Masakazu Furuta1, Elena Constantinoiu1, Taeko Nakamura1, Natsuko
Tanaka1, Mari Fujimoto1, Toshio Hayashi1, Masamichi Iwama2, Mituhiro
Murata3, and Dan W. Urry4; 1Osaka Prefecture University, 1-2, Gakuen-cho,
Sakai, Osaka 599-8570, Japan, 2Bioelastics Japan, 11-20, Midori-ku,
Yokohama, Kanagawa 226-0003 Japan, 3JSR Co., Ltd. 25, Miyukigaoka,
Tsukuba, Ibaraki 305, Japan 4. University of Minnesota, St. Paul, Minnesota,
U.S.A., and Bioelastics Research, Ltd., Birmingham, Alabama, U.S.A.,
mfuruta@b.s.osakafu-u.ac.jp
269
Poster Abstracts
Elastic protein-based polymers were prepared by recombinant DNA technology and based
on the GVGVP repeat amino acid sequence of tropoelastin. Under specified conditions,
such as a temperature above30oC, They can be coacervated to form nano-particles and
stabilized by crosslinking with gamma-rays that pass through a 0.22 nm filter and exhibit
diameters of less than ca. 150 nm and a narrow size distribution. Yield of the
gamma-cross-linked nano-particles increases with increasing dose but is insensitive to
dose rate. Here we report their use in drug delivery. In particular, time-release profiles for
Biebrich Scarlet Red gave results equivalent to those of previously reported
gamma-cross-linked discs made of the same polymer. Thus, this controlled release device
can deliver drugs to sites accessible by small caliber hypodermic syringes. Some other
anticancer drugs are being examined for loading and releasing to the crosslinked peptides
and favorable results are being collected.
P2
362
MELITTIN-LIPID INTERACTIONS: A COMPARISON BETWEEN
LIPOSOMES AND POLYMER-STABILIZED NANODISCS.
Per Wessman, Anna Lundquist, Katarina Edwards, Department of Physical
and Analytical Chemistry, Uppsala University, Box 579, SE-751 23 Uppsala,
Sweden; per.wessman@fki.uu.se
Liposomes have during the last decades been extensively used as model membranes in
studies aiming at the investigation of peptide-lipid interactions. The results of
liposome-based investigations have greatly increased our knowledge and understanding of
the effects caused by various peptides on structure, permeability and other important
qualities of lipid bilayers. In order to compare and evaluate data obtained under different
conditions, e.g. at varying lipid composition/concentration or temperature, detailed
knowledge about the partition behavior is required. Unfortunately the self-closed, and
frequently multilamellar, structure of liposomes may lead to difficulties when evaluating
partition data. We have recently developed a new type of nano-sized model membranes,
the PEG-stabilized bilayer discs, which avoid the above problem. The discs show excellent
temperature and long term stability, and their open structure ensures that peptides have full
access to both leaflets of the bilayer. In the present study we used melittin as a model
peptide to investigate and compare the partition behavior in systems containing liposomes
and discs, respectively. For these studies, which included bilayers with several different
lipid compositions, we employed a spectroscopic method based on changes in the intrinsic
fluorescence of melittin. Further, the obtained partition coefficients were, for certain
selected systems, used to compare and correlate the effect of melittin on properties such as
permeability and structure of the model membranes.
P2
363
270
NIMODIPINE-NANOLIPOSOMES: PREPARATION,
CHARACTERIZATION AND PHARMACOKINETICS IN RAT
Guifang Zhang, Department of Pharmaceutics, University of Minnesota, 308
Harvard St. SE, Minneapolis, MN, 55455, USA; and Jiabi Zhu, Xian Zhu and
Poster Abstracts
Shan Li. College of Pharmacy, China Pharmaceutical University, Nanjing,
210009, P. R. China; zhang337@umn.edu
The purpose of this study was to improve the solubility, stability and enhance the brain
target efficiency of nimodipine by preparing a formulation as nanoliposome. A lyophilized
powder of nimodipine-nanoliposomes were prepared using the ethanol dripping-sonicating
dispersion-freeze drying technique. The formulation consisted of
eggPC:cholesterol:sodium deoxycholate:tween-80 = 8: 1: 4.5: 2.25 (by mass) with drug
load 0.42%. Mannitol (70 % by total mass) was added as a protective agent for freeze
drying. Following reconstitution in normal saline, the mean particle size was 18.9 nm, and
the entrapment efficiency was 96.8 ± 1.3%. The lyophilized powder was found to be stable
during one year storage in sealed ampules in dark and room temperature. No change in the
particle size or entrapment efficiency was detectable for 10 hours test following
reconstitution. Nimodipin-nanoliposomes were administered to rats by short IV infusion
and the resulting serum and tissue concentrations were determined by HPLC and compared
to the IV infusion of the commercial nimodipine solution (0.5mg/kg). The Cmax, AUC, and
MRT were significantly greater and ke and CLs were smaller for
nimodipine-nanoliposome compared to the nimodipine solution. For brain tissue, the
targeted efficiency was 6.02 based on the AUC ratio for nimodipine-nanoliposome versus
2.80 for the solution. The results demonstrate that entrapment of nimodipine in
nanoliposomes decreases the elimination and increases the tissue bioavailability of
nimodipine and the brain targeted efficiency in rats. Thus, the nanoliposome formulation
provides for greater stability and targeting over the existing commercially available
solution.
P2
364
DETERMINING THE DISPERSION BEHAVIOR OF FORMULATED
BULK DRUG USING LIGHT DIFFRACTION ANALYSIS
Maria R. Toler, Pfizer, Inc., 7000 Portage Rd., Kalamazoo, MI
49001;maria.r.toler@Pfizer.com
Understanding how a drug will disperse in a selected media is desirable for predicting
in-vivo behavior and designing an appropriate formulation. A novel approach to particle
size analysis is presented here, outlining the use of this technology for describing the
dispersion behavior of formulated drug. Two case studies are presented: A quick dissolve
tablet and an oral suspension. Traditional light diffraction particle size analysis (wet
dispersion) involves the selection of an appropriate dispersing agent and adequate energy
to the sample to provide a well dispersed system. In determining the dispersion behavior of
drug particles, the media is chosen based on the question to be answered. In the case of a
quick dissolve tablet, rapid disintegration and mouth feel are important to a satisfactory
formulation. Dispersion behavior in artificial saliva was evaluated. In the case of an oral
suspension made using a fairly insoluble micronized drug, the presence of aggregates in
the suspension greatly affected bioavailability. The determination of the degree of
aggregation in dissolution media was critical to predicting bioavailability and formulating
an appropriate suspension. We emphasize that optical microscopy plays a critical role in
271
Poster Abstracts
the evaluation of dispersion behavior. This, along with light diffraction particle size
analysis can provide critical input to predicting adequate performance of a formulation.
P2
365
GIANT PHOSPHOLIPID VESICLES AS A POSSIBLE SYSTEM FOR
STUDYING INTERACTIONS OF MEMBRANES WITH ANTIBODIES
Jasna Urbanija1, Blaž Rozman2, Aleš Iglič3, Veronika Kralj-Iglič2,4, 1Faculty
of Medicine, University of Ljubljana, Ljubljana, Slovenia; 2Department of
Rheumatology, Clinical Center, Ljubljana, Slovenia; 3Faculty of Electrical
Engineering, University of Ljubljana, Ljubljana, Slovenia;
jasna.urbanija@biofiz.mf.uni-lj.si
Antiphospholipid syndrome (APS) is an autoimmune disease characterized by thrombotic
events and/or pregnancy morbidity. The etiology and underlying mechanisms of APS are
not yet understood, however, activation of the coagulation system is evident.
Antiphospholipid antibodies are present in the sera of patients with APS. These antibodies
were found to interact directly with phospholipids constituting cell membranes (e.g.
cardiolipin) or to bind to an antigen beta2-glycoprotein1 (ß2GPI). Therefore giant
phospholipid vesicles (GPV) were prepared with three different lipids: POPC, cholesterol
and cardiolipin in proportions 2:2:3, respectively. With such selection of lipids we
approach the actual constitution of biological membranes involved in APS and make the
GPV stable even for days. Interactions between GPV, antibodies and ß2GPI were studied
under phase contrast microscope. The change of morfology of GPV due to addition of
different antibodies as well as ß2GPI, could provide us with better understanding of the
effects of antibodies on biological processes in patients with APS. Strong adhesion of
vesicles to each other and to the ground was observed, together with suppression of
vesicles contour fluctuations, enhancement of the contrast of the vesicle contour,
permeabilisation of vesicle membrane to sugar resulting in dissapearance of the contrast
between the vesicle interior and exterior, lateral segregation of the membrane constituents
and bursts of vesicles. Our results indicate that antibodies and antigens may have an
important role in the formation of complexes composed of cells, membrane fragments and
proteins - complexes which are important in blood clot formation.
272
Preregistered Conferees
Index of Speakers/Presenters
(Alphabetically With Paper Number)
Akiyoshi, Kazunari – 6
Alasundaram, Ganesan – 277
Allen, Christine – 84
Almeida, José F. – 332
Amsden, Brian G. – 18
Arifin, Dian R. – 218
Asai, Tomohiro – 347
Asher, Sandy – 95
Backer, Joseph – 177
Barbé, Christophe J. – 152
Bauer, Christina A. – 333
Bäumler, Hans – 2
Benson, James R. – 108
Berkland, Cory – 194
Berret, Jean–François – 32
Berret, Jean–Francois – 334
Bhowmick, Tridib K. – 197
Bill Turnell – 262
Blanchard, Jim – 109
Boch, Ron – 101
Bogan, Mike – 46
Bonroy, K. – 213
Boyle, Ross W. – 250
Braun, Paul – 139
Brayner, Roberta –64, 340
Bringley, Joseph F. – 189
Brown, David P. – 305
Brown, Larry – 221
Bumiller, Mark – 107
Bunjes, Heike – 17
Burgess, Diane – 90
Burkhard, Peter – 229
Burnett, Daniel J. – 278, 279, 324,
325
Caffrey, Martin – 35
Caldwell, Karin – 33
Caliceti, Paolo – 273
Camata, Renato P. – 188
Carbone, Roberta – 92
Carmona–Ribeiro, Ana M. – 203
Castro, Lizandra – 311
Celis, Maria–Teresa – 12, 184
Chakrapani, Aravind – 146
Chan, Chak K. – 47
Chen, Wei – 66
Chertok, Beata – 342
Cho, Chong–Su – 226
Chow, Gan–Moog – 198
Clausi, Amber – 312
Cliffel, David E. – 79
Colvin, Vicki – 59
Cook, Robert – 110
Coulter, Kent – 52
Couzis, Alexander – 36
Dai, Yujie – 154
Dan, Nily – 156
Darlington, Jerald W. – 331
Darvari, Ramin – 217
De Geest, Bruno G. – 142, 330
De Theije, Femke – 212
Delair, Thierry – 204
DeLong, Robert – 196
Derwinska, Katarzyna – 343
DeSimone, Joe – 186
Dihang, Hélène – 42
Driscoll, David – 11
Drummond, Daryl – 37
Duarte, Ana Rita C. – 269, 314
Duguet, Etienne – 335
Durant, Yvon – 211
Dybiec, Maciej – 344
273
Speaker/Presenter Index
Dziewiszek, Krzysztof J. – 219
Ebert, Katrin – 149
Edsman, Katarina – 19
Egito, E. Sócrates. T. – 296, 297,
359, 360
Enriquez, Iris V. – 114
Etzler, Frank M. – 43
Euliss, Larken E. – 328
Eversdijk, Jacco – 158
Fahr, Alfred – 245
Farnsworth, Stan – 193
Fischbach, Ingrid – 180
Fischer, Sabine – 22
Florence, A.T. (Sandy) – 173
Fonnum, Geir – 165
Forsayeth, John – 31
Foster, Neil – 267
Frank, Matthias – 172
Fransén, Nelly – 329
Friggeri, Arianna – 5
Frimpong, Reynolds A. – 235
Fritzsche, Wolfgang – 168, 310
Fujii, Gary – 201
Furuta, Masakazu – 361
Galperin, Anna – 295
Gamazo, Carlos – 58
Gao, Xiaohu – 253
Gardner, David L. – 237
Giersig, Michael – 7
Goia, Dan V. – 4
Goins, Beth – 214
Gold, Lynn – 13
Goldberg, Eugene – 144
Golomb, Gershon – 100
Gower, Laurie – 97
Grant, Gilbert – 127
Green, Jennifer A. – 134
Gruverman, Irwin – 10
Gupta, Ram B. – 136
274
Haas, Heinrich – 170
Hain, Jessica – 327
Happawana, Gemunu – 246
Harms, Meike – 266, 326
Harms, Meike – 326
Hedderich, Regine – 317
Heitfeld, Kevin A. – 276
Herold, Marc – 29, 301, 302
Hino, Tamoaki – 56
Hjelm, Rex P. – 82
Hoerr, Robert – 15
Hofmann, Heinrich – 185
Hook, Sarah – 309
Horozov, Tommy – 148
Howdle, Steve – 133
Hu, Min – 67
Hu, Jianhua – 290
Huettmann, Gereon – 68
Hurt, Robert – 199
Hütten, Andreas – 123
Hwang, Sung–Joo – 138
Hyeon, Taeghwan – 119
Ichikawa, Hideki – 159
Ivkov, Robert – 70
Iwamoto, S. – 50
Jacobs, Irwin C. – 23
Jans, Hilde – 256
Jia, Xinqiao – 98
Jin, Yiguang – 190
Johansson, Christian – 183
Johnston, Keith – 132
Jørgensen, Kent – 86
Josefsen, Leanne B. – 72
Joshi, Hemant – 182
Juillerat–Jeanneret, L. – 232
Jung, Jae–Eun – 358
Kamau, Sarah W. – 223
Kamps, Jan A.A.M. – 38
Kaneda, Shinichi – 39
Preregistered Conferees
Kauppinen, Esko – 53
Kell, Arnold J. – 300
Kim, Bum Gil – 357
Kim, Eun–Jung – 288
Kim, Gloria J. – 248
Kollar, Csilla – 16
Kompella, Uday – 105
Kono, Kenji – 129
Koynova, Rumiana – 89
Krauss, Todd D. – 77
Kuhn, Liisa T. – 289
Kumar, Venisetty R. – 274, 275
Lau, Kenneth K. S. – 24
Lavasanifar, Afsaneh – 83
Leblanc, Roger – 73
Lee, Bob (RJ) – 117
Lee, Jim – 187
Lee, Jonghwi – 141
Lee, Robert W. – 263
Lee, Sang–Kyung – 225
Lee, Yongwoo – 356
Legastelois, Stephane – 257
Lerche, Dietmar – 49, 151, 308
Leubner, Ingo – 181
Leuenberger, Hans – 244
Leupold, Eik – 323
Li, Chun – 265
Li, Pei (Pauline) – 94
Li, Yuzhuo – 27
Li, Zhengmao – 103
Lich, Ben – 307
Lin, Victor – 176
Lipp, Michael – 240
Liu, Jubo – 355
Liu, Tao – 255
Low, P. – 115
Lowe, Tao L. – 178
Loxley, Andrew – 55
Lu, Wei – 153
Lu, Yi – 207
Luby, Thomas – 202
Luo, Dan – 40
Ma, Dongling – 247
MacCuspie, Robert I. – 208
Maeda, Mizuo – 87
Mailänder, Volker – 80
Mak, Wing Cheung – 167
Margel, Shlomo – 26
Markland, Peter – 161
Martin, Andrew – 238
Martins, Sofia – 339
Masuda, Yoshitake – 287
Matsunaga, Terry – 28
Mattoussi, Hedi – 74
McGrath, James L. – 200
Miyata, Takashi – 140
Morimoto, Nobuyuki – 286
Morrison, Shannon – 192
Moudgil, Brij – 236
Muhrer, Gerhard – 271
Müller, Rainer H. – 179
Müller, Angelika – 341
Müller–Schulte, Detlef – 75, 160,
298, 299
Mulvaney, Shawn P. – 164
Murtomaa, Matti – 241
Musyanovych, Anna – 99
Nakamura, Hiroyuki – 220
Nakamura, Michihiro – 285
Nandi, Indranil – 128
Narasimhan, Balaji – 205
Nath, Sudip – 291
Navailles, Laurence – 131
Needham, David – 215
Ng, Boon Sing – 283
Nilsen, Thor – 175
Nisisako, Takasi – 14
Nooney, Robert – 254
275
Speaker/Presenter Index
Odukale, Anika A. – 284
Oku, Naoto – 69
Oreskovic, Tammy – 316
Otake, Katsuto – 270
Ozer, Ozgen – 147
Paciotti, Giulio – 3
Panchapakesan, Balaji – 116
Parak, Wolfgang – 96
Park, Chul Ho – 282
Park, Sang–Eun – 337
Park, Sang Im – 346
Parker, Andrew – 306
Pelton, Robert – 228
Perez, J. Manuel – 252
Petri, Dense F.S. – 169
Petry, Harald – 93
Pirollo, Kathleen F. – 113
Pishko, Michael – 155
Ponce, Sara – 354
Porter, Marc – 122
Preece, Jon – 88
Qi, Sheng – 157, 353
Raula, Janne – 303
Ravenelle, Francois – 85
Rehrig, Rick – 162
Rogueda, Philippe – 104, 239, 304
Rojas, Edith C. – 352
Rosenthal, Sandy – 102
Rotello, Vince – 25
Rothrock, Ginger Denison – 280
Russo, Paul S. – 120
Saez–Martinez, Virginia – 281
Saini, Divey – 349
Sampaio de Sousa, A.R. – 313
Sandler, Niklas – 242
Santra, Swadeshmukul – 171
Sawafta, Reyad – 30
Scott, Terrence – 130
Seino, Satoshi – 9
276
Shao, Jun – 251
Sharma, Jaswinder – 294, 338
Sheff, David – 216
Shekunov, Boris – 135
Sievers, Bob – 137
Sitdikov, Ravil A. – 348
Smaïhi, Monique – 234
Smirnov, Alex I. – 322
Sokolov, Igor – 57, 293
Somasundaran, Ponisseril – 20
Starostina, Natasha – 45
Stone, Vicki – 195
Straub, Julie – 8
Sullivan, Sean – 222
Svenson, Sonke – 174
Swai, Hulda Shaidi – 351
Szebeni, Janos – 62
Szoka, Francis – 1
Talton, James – 143
Tan, Wee Beng – 91, 292
Taubert, Andreas – 51
Thanh, Nguyen TK – 126
Thomas, Dave – 125, 259
Thompson, David – 34, 224
Tinke, A.P. – 44
Tofoli, Giovana R. – 315
Toler, Maria R. – 364
Torchilin, Vladimir – 81
Trau, Dieter – 21
Tsikhudo, Robert M. – 78
Tung, Hsien–Hsin – 233
Uchegbu, Ijeoma F. – 261
Uddin, Mohammad S. – 121
Urbanija, Jasna – 365
Vail, Neal K. – 191
van den Bergh, Hubert – 65
Van der Wood, Tim B. – 48
van Nostrum, Cornelus F. – 71
Van Thienen, Tinneke – 163
Preregistered Conferees
van Veggel, Frank – 209
Varaksa, Natalia – 63
Vasseur, Sebastien – 249
Veiseh, Omid – 231
Velev, Orlin D. – 206
Velikov, Krassimir P. – 321
Verreck, Geert – 272
von Rechenberg, Brigitte – 118
Vu, Tania Q. – 210
Waligorski, Amy M. – 106
Wang, Yongxian – 76
Wang, Chang Chun – 145
Watts, Daniel J. – 61
Wegner, Karsten – 345
Wendorf, Janet R. – 350
Wessman, Per – 362
Williams, P. Stephen – 41
Wirix–Speetjens, Roel – 166
Woodle, Martin – 264
Worden, James – 230
Wu, X.Y. (Shirley) – 112
Wuang, Shy Chyi – 124, 320
Yamasaki, Yuichi – 54
Yang, Hong – 60
Yates, Matt – 268
Yoshizawa, Hidekazu – 150
Yu, Ji–Hun – 336
Yu, Kui – 260
Yun, Jimmy – 111, 243
Zhang, Guifang – 363
Zhang, Jin – 258
Zumstein, Lou – 227
277
Speaker/Presenter Index
Preregistered Conferees
Dean Abadzic
LUM Corporation
200 Boston Avenue, Suite 2900
Medford, MA 02155
dean@lumanalytical.com
Kazunari Akiyoshi
Institute of Biomaterials & Bioengineering
Tokyo Medical and Dental University
2-3-10 Kanda-Surugadai, Chiyoda-ku
Tokyo 101-0062, Japan
akiyoshi.org@tmd.ac.jp
Buket Aksu
EGE University
Okmeydani-Borucicegi-20
34382 Sisli, Istanbul, Turkey
nbaksu@superonline.com
Christine Allen
University of Toronto
19 Russell Street
Toronto, Ontario, M5S 2S2, Canada
José Filipe da Silva Lapas Almeida
University of Coimbra-ITQB-UNL
Pinhal de Marrocos-Polo II
3030-290 Coimbra, Portugal
falmeida@itqb.unl.pt
Brian Amsden
Queen’s University
Dupuis Hall
19 Division Street
Kingston, Ontario, K7L 3N6, Canada
amsden@chee.queensu.ca
Marc Anton
INRA
Rue de la Géraudière
BP 71627
Nantes 44316, France
anton@nantes.inra.fr
Dian Arifin
Monash University
Dept of Mechanical Engineering
Clayton Campus, Wellington Road
Clayton, VIC 3800, Australia
dian.arifin@eng.monash.edu.au
Agu Artma
Solis BioDyne
Pikk 14
51013 Tartu, Estonia
agu.artma@sbd.ee
278
Tomohiro Asai
University of Shizuoka
52-1, Yada, Suruga-ku
422-8526 Shizuoka, Japan
asai@u-shizuoka-ken.ac.jp
Sanford Asher
University of Pittsburgh
701 Chevron Science Center
219 Parkman Avenue
Pittsburgh, PA 15260
asher@pitt.edu
Joseph Backer
SibTech, Inc.
705 North Mountain Road
Newington, CT 06111
jbacker@sibtech.com
Ganesan Balasundaram
Brown University
Division of Engineering
182 Hope Street
Providence, RI 02912
gbala@brown.edu
Rebanta Bandyopadhyay
Dr. Reddy’s Laboratories Limited
Bollaram Road, Miyapur
Hyderabad, Andhra Pradesh
500 049, India
rebantab@drreddys.com
Christophe Barbé
Australian Nuclear Science &
Technology Organisation
ANSTO-CeramiSphere, Bldg 3, PMB 1
Menai, NSW, 2234, Australia
cab@ansto.gov.au
Stan Barnett
Merck & Co., Inc.
201 Hemlock Circle
North Wales, PA 19454
stan_barnett@merck.com
Christina Bauer
Sandia National Laboratories
7011 East Avenue
Bldg. 916, MS-9161
Livermore, CA 94550
cbauer@sandia.gov
Preregistered Conferees
Hans Bäumler
Charité–Universitätsmedizin Berlin
Schumannstrasse, 20/21
D-10117 Berlin, Germany
hans.baeumler@charite.de
Rina Ben Shabat
Bar-Ilan University
Chemistry Dept
Ramat-Gan, 52900, Israel
rinabenshabat@hotmail.com
James Benson
Polygenetics, Inc.
PO Box 33115
Los Gatos, CA 95031
j-benson@polygenetics.com
Cory Berkland
University of Kansas
2030 Becker Drive
Lawrence, KS 66047
berkland@ku.edu
Jean-Francois Berret
CNRS-Université Paris 7
Matière et Système Complexes
140 rue de Lourmel
Paris, 75015, France
jean-francois.berret@ccr.jussieu.fr
Tridib Bhowmick
Indian Institute of Technology Bombay
Chemical Engineering
Powai, Maharashtra
Mumbai-400076, India
tbhowmich@iitb.ac.in
Ron Boch
QLT Inc.
887 Great Northern Way
Vancouver, British Columbia V5T 4T5
Canada
rboch@qltinc.com
Michael Bogan
Lawrence Livermore National Lab
7000 East Avenue, L-211
Livermore, CA 94550
bogan2@llnl.gov
Kristien Bonroy
Interuniversitair Micro-Electronica
Centrum (IMEC)
Kapeldreef 75
Heverlee 3001, Belgium
bonroyk@imec.be
Ross Boyle
University of Hull
Chemistry & Clinical Biosciences Institute
Cottingham Road
Kingston-upon-Hull, East Yorkshire, HU6 7RX
United Kingdom
r.w.boyle@hull.ac.uk
Paul Braun
University of Illinois at Urbana-Champaign
204A MSEB, MC 246
1304 West Green Street
Urbana, IL 61801
pbraun@uiuc.edu
John Bishop
JB Particle Technology
2251-4 East Main Street
Rochester, NY 14609
johnfbishop@hotmail.com
Roberta Brayner
Interfaces, Traitements, Organisation de
Dynamique des Systèmes (ITODYS)
UMR-CNRS 7086
Université Paris 7-Denis Diderot
case 7090, 2 place Jussieu
75251 Paris Cedex 05, France
brayner@ccr.jussieu.fr
Jason Bjork
3M Company
3M Center, Bldg 270-2N-03
St. Paul, MN 55144
jason_bjork@mmm.com
Joseph Bringley
Eastman Kodak Company
Research Laboratories
Rochester, NY 14650-02002
joseph.bringley@kodak.com
James Blanchard
Aradigm Corp.
3929 Pt. Eden Way
Hayward, CA 94545
blanchardj@aradigm.com
Beth A.-S. Brown
Cima Labs
10000 Valley View Road
Eden Prairie, MN 55344
beth.brown@cimalabs.com
279
Preregistered Conferees
David Brown
Helsinki University of Technology
Nanomaterials Group
Biologinkuja 7
02044 VTT Espoo, Finland
david.brown@vtt.fi
Martin Caffrey
University of Limerick
Plassey Drive
Limerick, Ireland
martin.caffrey@ul.ie
Larry Brown
Epic Therapeutics, Inc.
220 Norwood Park South
Norwood, MA 02062
larry_brown@baxter.com
Karin Caldwell
Uppsala University
Physical and Analytical Chemistry
Box 577, BMC
Uppsala, 75123, Sweden
karin.caldwell@biosurf.uu.se
Michael Brown
CPS Instruments, Inc.
3755 Green Ridge Road
Furlong, PA 18925
mgba@voicenet.com
Paolo Caliceti
University of Padua
Via F. Marzolo 5
Padova, 35131, Italy
paolo.caliceti@unipd.it
Mark Bumiller
Malvern Instruments
10 Southville Road
Southboro, MA 01772
mark.bumiller@malvernusa.com
Renato Camata
University of Alabama at Birmingham
rd
1530 3 Avenue S, CH310
Birmingham, AL 35294
camata@uab.edu
Heike Bunjes
Jena University
Pharmaceutical Technology
Lessingstrasse 8
07743 Jena, Germany
heike.bunjes@uni-jena.de
Raffaele Cammarano
iCeutica
33 Montreal Street
Fremantle, WA, 6160, Australia
raff@iceutica.com
Christopher Burcham
Eli Lilly and Company
Chemical Process R&D
Indianapolis, IN 46285
cburcham@lilly.com
Diane Burgess
University of Connecticut
School of Pharmacy
69 North Eagleville Road
Storrs, CT 06269
d.burgess@uconn.edu
John Caola
FEI Company
5350 NE Dawson Creek Drive
Hillsboro, OR 97124
adkraker@feico.com
Roberta Carbone
European Institute of Oncology
Dept Experimental Oncology
via Ripamonti 435
20141 Milan, Italy
roberta.carbone@ifom-ieo-campus.it
Peter Burkhard
University of Connecticut
97 North Eagleville Road, Unit 3136
Storrs, CT 06269
peter.burkhard@uconn.edu
Ana Maria Carmona-Ribeiro
Instituto de Química-Universidade de São Paulo
Caixa Postal 26077
Av Prof Lineu Prestes 748
São Paulo,CEP 05513-970, Brazil
amcr@usp.br
Daniel Burnett
Surface Measurement Systems
2222 South 12th Street, Suite D
Allentown, PA 18103
burnett@smsna.com
Lizandra Belmonte Rodrigues de Castro
Instituto de Química-Universidade de São Paulo
Av Prof Lineu Prestes 748, bloco03
São Paulo,05508-900, Brazil
licastro@iq.usp.br
280
Preregistered Conferees
Maria Teresa Celis
University of The Andes
Lab. FIRP and Lab. POLYCOL
Facultad de Inginiería
Mérida, 5101, Venezuela
celismt@ula.ve
Aravind Chakrapani
The Ohio State University
270 Bevis Hall
1080 Carmack Road
Columbus, OH 43210
aravind@bme.ohio-state.edu
Chak K. Chan
Hong Kong University of Science & Technology
Chemical Engineering
Clear Water Bay
Hong Kong SAR, China
keckchan@ust.hk
Hui Chen
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway, Suite 400
Orlando, FL 32826
huichen@mail.ucf.edu
Tongqian Chen
Sirna Therapeutics, Inc.
2950 Wilderness Place
Boulder, CO 80301
chent@sirna.com
Gan-Moog Chow
National University of Singapore
Materials Science & Engineering
Kent Ridge, 119260, Singapore
msecgm@nus.edu.sg
Amber Clausi
University of Colorado at Boulder
Chemical & Biological Engineering
1111 Engineering Drive
Boulder, CO 80309
amber.clausi@colorado.edu
David Cliffel
Vanderbilt University
VU Station B 351822
Nashville, TN 37235
d.cliffel@vanderbilt.edu
Vicki Colvin
Rice University
Center for Biological & Environmental
Nanotechnology
6100 Mail Street, MS-63
Houston, TX 77005
colvin@rice.edu
Robert Cook
MAP Pharmaceuticals
2400 Bayshore Parkway
Mountain View, CA 94403
rcook@mappharma.com
Wei Chen
Nomadics, Inc.
1024 South Innovation Way
Stillwater, OK 74074
wchen@nomadics.com
John Corte
Merck & Co., Inc.
PO Box 2000
RY 814-S200
Rahway, NJ 07065
john_corte@merck.com
Beata Chertok
University of Michigan
College of Pharmacy
428 Church Street
Ann Arbor, MI 48109
beata@umich.edu
Kent Coulter
Southwest Research Institute
6220 Culebra Road (78238-5166)
PO Drawer 28510
San Antonio, TX 78228-0510
kent.coulter@swri.edu
Chong-Su Cho
Seoul National University
School of Agricultural Biotechnology
San 56-1, Sillim-dong, Kwanak-gu
Seoul, 151-742, South Korea
chocs@plaza.snu.ac.kr
Alexander Couzis
The City College of New York
Chemical Engineering
140th Street at Convent Avenue
New York, NY 10031
couzis@ccny.cuny.edu
Hoo-Kyun Choi
Chosun University
College of Pharmacy
375 Seosuk-dong
Gwangju, 501-759, Korea
hgchoi@chosun.ac.kr
Qiu Dai
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway, Suite 400
Orlando, FL 32826
qiudai@creol.ucf.edu
281
Preregistered Conferees
Yujie Dai
Tianjin University of Science & Technology
Hexi Qu, Dagu Nanlu, 1038
Tianjin, 300222, China
yjdai@126.com
Nily Dan
Drexel University
Chemical & Biological Engineering
3141 Chestnut Street
Philadelphia, PA 19104
dan@coe.drexel.edu
Jerry Darlington
AMCOL International
1500 West Shure Drive
Arlington Heights, IL 60004
jerry.darlington@amcol.com
Thierry Delair
UMR CNRS-bioMérieux
ENS-Lyon
46, allée d’Italie
Lyon, 69007, France
Thierry.Delair@ens-lyon.fr
Rob DeLong
Louisburg College
501 North Main Street
Louisburg, NC 27549
rdelong@louisburg.edu
Ron Demers
Merck Eprova
5628 Ptarmigan Place
North Vancouver, British Columbia, V7R 4S3
Canada
ron.demers@demerconsulting.ca
Ramin Darvari
Epic Therapeutics, Inc.
220 Norwood Park South
Norwood, MA 02062
ramin_darvari@baxter.com
Katarzyna Derwinska
ARC Seibersdorf Research GmbH
Seibersdorf, 2444, Austria
katarzyna.derwinska@arcs.ac.at
Sridhar Dasaratha
3M Company
3M Center, 270-2N-03
St. Paul, MN 55144-1000
dvsridhar@mmm.com
Tejas Desai
Vasogen Inc.
2155 Dunwin Drive
Mississauga, Ontario, L5L 4M1, Canada
tdesai@vasogen.com
Allan David
ISTN, Inc.
2101 Pennsylvania Avenue
York, PA 17404
aedavid@istninc.com
Joseph DeSimone
University of North Carolina at Chapel Hill
Dept of Chemistry
CB #3290 Venable Hall
Chapel Hill, NC 27599
desimone@unc.edu
Bruno De Geest
Ghent University
Dept of Pharmaceutics
Harelbekestraat 72
Ghent, 9000, Belgium
br.degeest@ugent.be
J. M. Devoisselle
UMR CNRS/ENSCM/UM1 5618
8, rue d el’école normale
Montpellier, 34296, France
jm.devoisselle@univ-montp1.fr
Femke de Theije
Philips Research
High Tech Campus 4 (WAG02)
Eindhoven, 5656 AE, The Netherlands
femke.de.theije@philips.com
Helene Dihang
Formulaction
10 impasse Borde Basse
L’Union, 31240, France
dihang@formulaction.com
Martyn Deal
GlaxoSmithKline
New Frontiers Science Park
rd
3 Avenue
Harlow, Essex, CM19 5AW
United Kingdom
martyn.j.deal@gsk.com
Kenneth Dormer
Hough Ear Institute
University of Oklahoma Health Sciences Center
th
3400 NW 56 Street
Oklahoma City, OK 73112
ken-dormer@ouhsc.edu
282
Preregistered Conferees
Joe Domingue
Surface Measurement Systems
th
2222 South 12 Street
Allentown, PA 18103
domingue@smsna.com
Yvon Durant
University of New Hampshire
G101 Parsons Hall
Durham, NH 03824
yvon.durant@unh.edu
Jakob Kisbye Dreyer
Novo Nordisk A/S
Device Chemistry and Biology
Brennum Park
Hillerød, DK-3400, Denmark
jkid@novonordisk.com
Maciej Dybiec
Moffitt Cancer Center
12902 Magnolia Drive
MRC-Cancont
Tampa, FL 33612
m.dybiec@eng.usf.edu
David Driscoll
BIDMC/Harvard Medical School
Baker Bldg, Suite 605
185 Pilgrim Road
Boston, MA 02215
ddriscol@bidmc.harvard.edu
Krzysztof Dziewiszek
Antigenics Inc.
3 Forbes Road
Lexington, MA 02421
kdziewiszek@antigenics.com
Daryl Drummond
Hermes Biosciences, Inc.
61 Airport Blvd, Suite D
South San Francisco, CA 94080
drummond@hermesbio.com
Ana Rita Duarte
IBET
Av. da Republica, EAN, qta do Merque
Oeiras, 2781-901, Portugal
rduarte@itqb.unl.pt
Etienne Duguet
ICMCB-CNRS/University of Bordeaux
87 ave du Dr. Albert Schweitzer
Pessac, 33608, France
duguet@icmcb-bordeaux.cnrs.fr
Katrin Ebert
GKSS Research Centre Geesthacht GmbH
Institute of Chemistry
Max-Planck-Strasse 1
Geesthacht, 21502, Germany
katrin.ebert@gkss.de
Katarina Edsman
Uppsala University
Dept of Pharmacy
Box 580
Uppsala, SE-751 23, Sweden
katarina.edsman@farmaci.uu.se
Marc Egen
Boehringer Ingelheim Pharma GmbH & Co. KG
Binger Strasse 173
55216 Ingelheim, Germany
judith.schweikert@ing.boehringer-ingelheim.com
Dave Duncalf
Iota NanoSolutions Ltd
MerseyBIO
Crown Street
Liverpool, L69 7ZB, United Kingdom
dave.duncalf@iotanano.com
E. Sócrates Egito
Federal University of Rio Grande do Norta
Rua Praia de Areia Branca, 8948
Natal-RN, 59094-450, Brazil
socrates@ufrnet.br
Andrew Dunham
Baxter Healthcare
Route 120 & Wilson Road
Round Lake, IL 60073
andrew_dunham@baxter.com
Iris Enriquez
University of Florida
5035 SW 78th Way
Gainesville, FL 32608
ive@ufl.edu
David Duracher
Flamel Technologies
Parc Club du Moulin à Vent
33 avenue du Dr. Georges Levy
Venissieux, 69693, France
duracher@flamel.com
Frank Etzler
Boehringer-Ingelheim Pharmaceuticals, Inc.
900 Ridgebury Road
Ridgefield, CT 06877
fetzler@rdg.boehringer-ingelheim.com
283
Preregistered Conferees
Larken Euliss
University of North Carolina
Dept of Chemistry, CB 3290
Chapel Hill, NC 27517
euliss@email.unc.edu
Jacco Eversdijk
TNO Science and Industry
De Rondom 1
Eindhoven, 5512AP, The Netherlands
jacco.eversdijk@tno.nl
Alfred Fahr
FSU Jena
Lessingstrasse 8
Jena, Thüringen, 07743, Germany
alfred.fahr@uni-jena.de
Stan Farnsworth
Nanotechnologies, Inc.
1908 Kramer Lane
Austin, TX 78758
stan.farnsworth@nanoscale.com
Ingrid Fischbach
BASF AG
GVC/F, J550
Ludwigshafen, 67056, Germany
ingrid.fischbach@basf.com
Sabine Fischer
TNO Science and Industry
De Rondom 1
PO Bus 6235
Eindhoven, 5600 HE, The Netherlands
sabine.fischer@tno.nl
Alexander Florence
University of London
The School of Pharmacy
29/39 Brunswick Square
London, WC1N 1AX, United Kingdom
ataylorflorence@aol.com
Geir Fonnum
Dynal Invitrogen Corporation
Svelleveien 29
Lillestrom, 2004, Norway
geir.fonnum@invitrogen.com
John Forsayeth
University of California at San Francisco
MCB226, 1855 Folsom Street
San Francisco, CA 94103
john.forsayeth@ucsf.edu
Sara Forssén
AstraZeneca R&D
Pepparredsleden 1
Mölndal, 43183, Sweden
sara.forssen@astrazeneca.com
284
Alison Foster
Iota NanoSolutions
Merseybio
Crown Street
Liverpool, L69 7ZB, United Kingdom
alison.foster@iotanano.com
Neil Russell Foster
University of New South Wales
School of Chemical Sciences & Engineering
Sydney, NSW, 2052, Australia
n.foster@unsw.edu.au
Matthias Frank
Lawrence Livermore National Laboratory
7000 East Avenue
Mail Stop L-211
Livermore, CA 94551
frank1@llnl.gov
Nelly Fransén
Uppsala University
Dept of Pharmacy, Box 580
Husargatan 3
Uppsala, 751 23, Sweden
nelly.fransen@farmaci.uu.se
Arianna Friggeri
Biomade Technology Foundation
Nijenborgh 4
Groningen, 9747 AG, The Netherlands
friggeri@biomade.nl
Reynolds Frimpong
University of Kentucky
Chemical & Materials Engineering
177 F. Paul Anderson Tower
Lexington, KY 40506
frimpr@uky.edu
Wolfgang Fritzsche
Institute of Physical High Technology
PO Box 100239
Jena, 07702, Germany
fritzsche@ipht-jena.de
Gary Fujii
Molecular Express, Inc.
13310 South Figueroa Street
Los Angeles, CA 90061
gfujii@molecularexpress.com
Mari Fujimoto
Osaka Prefecture University
Gakuen-cho 1-2, Naka-ku
Sakai, Osaka, 599-8570, Japan
fujimoto05@b.s.osakafu-u.ac.jp
Preregistered Conferees
Masakazu Furuta
Osaka Prefecture University
Graduate School of Sciences
1-2, Gakuen-cho
Sakai, Osaka, 599-8570, Japan
mfuruta@b.s.osakafu-u.ac.jp
Lynn Gold
Sonus Pharmaceuticals. Inc.
th
22026 20 Avenue SE
Bothell, WA 98021
zannep@sonuspharma.com
Anna Galperin
Bar-Ilan University
Chemistry Dept
Ramat-Gan, 52900, Israel
ch111@mail.biu.ac.il
Eugene Goldberg
University of Florida
317A MAE, Box 116400
Gainesville, FL 32611
egold@mse.ufl.edu
Carlos Gamazo
University of Navarra
Irunlarrea, 1
Pamplona, 31008, Spain
cgamazo@unav.es
Gershon Golomb
The Hebrew University
School of Pharmacy, Faculty of Medicine
12065 Ein Kerem
Jerusalem, 91120, Israel
golomb@md.huji.ac.il
Ying Gao
Enzon Pharmaceuticals, Inc.
20 Kingsbridge Road
Piscataway, NJ 08854
yingao99@yahoo.com
David Gardner
Respirics, Inc.
6008 Triangle Drive, Suite 101
Raleigh, NC 27617
dgardner@respirics.com
Michael Giersig
caesar Research Center
Ludwig-Erhard-Allee 2
53175 Bonn, Germany
giersig@caesar.de
Thierry Glauser
Guidant
Lakeside Drive, S210
Santa Clara, CA 95054
tglauser@guidant.com
William Glover
University of Sydney
Sydney, NSW, Australia
wglover@pharm.usyd.edu.au
Dan Goia
Clarkson University
CAMP 344, Box 5814
Potsdam, NY 13699-5814
goiadanv@clarkson.edu
Beth Goins
University of Texas Health Science Center
at San Antonio
Radiology Dept MSC 7800
7703 Floyd Curl Drive
San Antonio, TX 78229-3900
goins@uthscsa.edu
Laurie Gower
University of Florida
112 Rhines Hall
Gainesville, FL 32611
lgowe@mse.ufl.edu
Gilbert Grant
New York University School of Medicine
Dept of Anesthesiology
550 First Avenue
New York, NY 10016
gilbert.grant@med.nyu.edu
Jennifer Green
Nektar Therapeutics UK Ltd
Unit 69 Listerhills Science Park
Campus Road
Bradford, West Yorkshire, BD7 1HR
England
jgreen@nektar.com
Irwin Gruverman
MFIC Corp. (Microfluidics Div.)
30 Ossipee Road
Newton, MA 02464
vcirv@alum.mit.edu
Florence Guimberteau
Flamel Technologies
Parc Club du Moulin a Vent
33 Avenue du Dr. G. Levy
Venissieux, 69693, France
bouchard@flamel.com
Yang Guo
Schering Plough Research Institute
2000 Galloping Hill Road
Kenilworth, NJ 07033
yang.guo@spcorp.com
285
Preregistered Conferees
Ram Gupta
Auburn University
161 Prather Lake Drive
Auburn, AL 36830
gupta@auburn.edu
Heinrich Haas
MediGene AG
Lochhamer Strasse 11
Martinsried, 82152, Germany
b.koehler@medigene.com
Jessica Hain
Dresden University of Technology
Mommsenstrasse 4
01069 Dresden, Germany
jessica.hain@chemie.tu-dresden.de
Gemunu Happawana
Southern Methodist University
Mechanical Engineering
5990 Airline Road
Dallas, TX 75275
happawan@engr.smu.edu
J. Zach Hilt
University of Kentucky
Chemical & Materials Engineering
177 F. Paul Anderson Tower
Lexington, KY 40506
hilt@engr.uky.edu
Tomoaki Hino
Kinjo Gakuin University
The College of Pharmacy
2-1723 Ohmori
Nagoya, Aichi, 463-8521, Japan
t-hino@kinjo-u.ac.jp
Rex Hjelm
Los Alamos National Laboratory
MS H-805
Los Alamos, NM 87545
hjelm@lanl.gov
Robert Hoerr
Nanocopoeia Inc.
1246 West University Avenue
St. Paul, MN 55104
bob.hoerr@nanocopoeia.com
Meike Harms
TU Braunschweig
Institute for Pharmaceutical Technology
Mendelssohnstrasse 1
38106 Braunschweig, Germany
meike.harms@tu-braunschweig.de
Heinrich Hofmann
Ecole Polytechnique Fédéral Lausanne (EPFL)
Powder Technology Laboratory, Station 12
Lausanne, CH-1015, Switzerland
heinrich.hofmann@epfl.ch
Regine Hedderich
Forschungszentrum Karlsruhe/NanoMat
PO Box 3640
D-76021 Karlsruhe, Germany
regine.hedderich@int.fzk.de
Nick Holerca
Colgate-Palmolive Company
909 River Road
Piscataway, NJ 08855
nick_holerca@colpal.com
Kevin Heitfeld
University of Cincinnati
3822 Kenker Place
Cincinnati, OH 45211
heitfeka@yahoo.com
Sarah Hook
University of Otago
PO Box 913
Dunedin, 9001, New Zealand
sarah.hook@stonebow.otago.ac.nz
Marc Herold
Fraunhofer IGB
Nobelstrasse 12
70569 Stuttgart, Germany
mhe@igb.fhg.de
Peyton Hopson
Vistakon, J&J Vision Care, Inc.
7500 Centurion Parkway
Jacksonville, FL 32256
phopson@visus.jnj.com
Rupert Herrmann
Roche Diagnostics GmbH
Nonnenwald 2
82372 Penzberg, Germany
rupert.herrmann@roche.com
Tommy Horozov
University of Hull
Cottingham Road
Hull, HU6 7RX, United Kingdom
t.s.horozov@hull.ac.uk
286
Preregistered Conferees
Steve Howdle
University of Nottingham
School of Chemistry
University Park
Nottingham, NG7 2RD, Great Britain
steve.howdle@nottingham.ac.uk
Sung Joo Hwang
Chungnam National University
College of Pharmacy
220 Gung-dong, Yuseong-gu
Daejeon, 305 764, Korea
sjhwang@cnu.ac.kr
Jianhua Hu
Fudan University
Macromolecular Science
220 Handan Road
Shanghai, 200433, China
hujh@fudan.edu.cn
Taeghwan Hyeon
Seoul National University
School of Chemical and Biological Engineering
Seoul, 151-744, South Korea
Min Hu
University of Washington
Dept of Chemistry
Box 351700
Seattle, WA 98195-1700
mhu2@u.washington.edu
Benjamin Hudson
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway
Orlando, FL 32826
auricpaladin@yahoo.com
John Hughes
AMCOL International
1500 West Shure Drive
Arlington Heights, IL 60004
john.hughes@amcol.com
Qun Huo
Nanoscience Technology Center of UCF
12424 Research Parkway, Suite 422
Orlando, FL 32826
qhuo@mail.ucf.edu
Robert Hurt
Brown University
Pathology and Laboratory Medicine
Providence, RI 02912
robert_hurt@brown.edu
Andreas Hütten
Forschungszentrum Karlsruhe GmbH
Hermann-von-Helmholtz-Platz 1
PO Box 3640
D-76021 Karlsruhe, Germany
andreas.huetten@int.fzk.de
Gereon Hüttmann
University of Lübeck
Institute for Biomedical Optics
Peter-Monnik-Weg 4
23562 Lübeck, SH, Germany
huettmann@bmo.uni-luebeck.de
Hideki Ichikawa
Kobe Gakuin University
Arise 518, Ikawadani-cho, Nishi-ku
Kobe, 651-2180, Japan
ichikawa@pharm.kobegakuin.ac.jp
Robert Ivkov
Triton BioSystems, Inc.
200 Turnpike Road
Chelmsford, MA 01824
rivkov@tritonbiosystems.com
Satoshi Iwamoto
Gifu University
1-1, Yanagido
Gifu, 501-1193, Japan
isatoshi@cc.gifu-u.ac.jp
Victor Jackson
University of Florida
205 Particle Science & Tech Bldg
PO Box 116135
Gainesville, FL 32611
dajackson@erc.ufl.edu
Irwin Jacobs
Particle and Coating Technologies, Inc.
5445 Highland Park Drive
St. Louis, MO 63110
ijacobs@pctincusa.com
Gunilla Jacobson
Stanford University
333 Campus Drive, #121
Stanford, CA 94305-5080
gunilla@stanford.edu
Hilde Jans
IMEC
Kapeldreef 75
Leuven 3001, Belgium
hilde.jans@imec.be
Daniel Jarmer
Merck & Co., Inc.
RY818-C314, PO Box 2000
Rahway, NJ 07065
daniel_jarmer@merck.com
287
Preregistered Conferees
Xinqiao Jia
University of Delaware
Materials Science & Engineering
201 DuPont Hall
Newark, DE 19716-3106
xjia@udel.edu
Christian Johansson
Uppsala University
Dept of Pharmacy
Box 580
Uppsala, 751 23, Sweden
christian.johansson@farmaci.uu.se
Keith Johnston
University of Texas
Chemical Engineering, CO400
Austin, TX 78704
kpj@che.utexas.edu
Kent Jørgensen
LiPlasome Pharma A/S
Technical University of Denmark
Bldg 207
Lyngby, DK-2800, Denmark
jorgense@liplasome.com
Leanne Josefsen
University of Hull
Cottingham Road
Kingston-upon-Hull, East Yorkshire, HU6 7RX
United Kingdom
r.w.boyle@hull.ac.uk
Charalambos Kaittanis
University of Central Florida
Nanoscience Technology Center
Orlando, FL 32826
ckaittan@mail.ucf.edu
Sarah Kamau
University of Zurich
Institute of Veterinary Biochemistry and
Molecular Biology
Winterthurerstrasse 190
CH-8057 Zurich, Switzerland
kamau@vetbio.unizh.ch
Jan A. A. M. Kamps
University Medical Center Groningen
Medical Biology
Hanzeplein 1
9713 GZ Groningen, The Netherlands
j.a.a.m.kamps@med.umcg.nl
Shinichi Kaneda
Terumo Corporation R&D Center
1500 Inokuchi, Nakai-machi
Ashigarakami-gun, Knagawa, 259-0151, Japan
shinichi_kaneda@terumo.co.jp
Joseph Kaparakis
University of Connecticut
539 Main Street
Torrington, CT 06790
joe_kap@hotmail.com
Hemant Joshi
Spectrum Pharmaceuticals
157 Technology Drive
Irvine, CA 92618
hjoshi@spectrumpharm.com
Esko Kauppinen
Helsinki University of Technology
Nanomaterials Group
Biologinkuja 7
Espoo, 02044 VTT, Finland
esko.kauppinen@vtt.fi
Lucienne Juillerat
University Institute of Pathology
25 rue du Bugnon
CH1011 Lausanne, Switzerland
lucienne.juillerat@chuv.ch
Arnold Kell
National Research Council of Canada
100 Sussex Drive, Room 1047
Ottawa, Ontario, K1A 0R6, Canada
arnold.kell@nrc.ca
Jae Eun Jung
Hanyang University
17, Haengdang-dong
Seongdong-gu
Seoul, 133791, South Korea
kdsuh@hanyang.ac.kr
Lars Kilaas
SINTEF Materials & Chemistry
Sem Sælandsv. 2A
Trondheim, 7465, Norway
lkilaas@sintef.no
Olev Kahre
Solis BioDyne OU
Pikk 14
Tartu, 51013, Estonia
olev.kahre@sbd.ee
288
Bum Gil Kim
Kyungwon University
San 65 Bokjeong-dong
Sungnam-city, Kyunggi-do, 461-701
Korea
magenta_kim@hotmail.com
Preregistered Conferees
Eun-Jung Kim
Chosun University
College of Pharmacy
375 Seoseok-dong, Dong-gu
Gwangju, 501-759, Korea
flora20@hanmail.net
Gloria Kim
Emory University and
Georgia Institute of Technology
Dept of Biomedical Engineering
101 Woodruff Circle, Suite 2001
Atlanta, GA 30322
gloria.kim@bme.gatech.edu
Jeong Geun Kim
Korea Kumho Petrochemical Co Ltd.
57-1, Hwaam-dong, Yuseong-gu
Deajeon, 305-348, Korea
k4solo@kkpc.com
Nini Hofslokken Kjus
Dynal Bead Based Separations
Invitrogen Corporation
Svelleveien 29
Lillestrom, 2004, Norway
nini.kjus@invitrogen.com
Klemen Kocevar
Lek d.d.
Verovskova 57
1526 Ljubljana, Slovenia
klemen.kocevar@sandoz.com
Csilla Kollar
Dow Corning Corp.
2200 West Salzburg Road
Midland, MI 48686
csilla.kollar@dowcorning.com
Uday Kompella
University of Nebraska Medical Center
985840 Nebraska Medical Center
Omaha, NE 68198-5840
ukompell@unmc.edu
Kenji Kono
Osaka Prefecture University
1-1, Gakuen-cho
Sakai, Osaka, 599-8531, Japan
kono@chem.osakafu-u.ac.jp
Andreas Kordikowski
Nektar Therapeutics UK Ltd.
Unit 69, Listerhills Science Park
Campus Road
Bradford, West Yorkshire, BD7 1HR
England
akordikowski@nektar.com
Rumiana Koynova
BMBCB Dept, Northwestern University
2205 Tech Drive
Evanston, IL 60208
r-tenchova@northwestern.edu
Andree Kraker
FEI Company
5350 NE Dawson Creek Drive
Hillsboro, OR 97124
adkraker@feico.com
Todd Krauss
University of Rochester
120 Trustee Road
Rochester, NY 14627-0216
krauss@chem.rochester.edu
Liisa Kuhn
University of Connecticut Health Center
263 Farmington Avenue, MC-1715
Farmington, CT 06030
lkuhn@uchc.edu
Mukesh Kumar
Dabur Research Foundation
22, Site IV, Sahibabad
Ghaziabad, U.P., 201010, India
mukeshk@dabur.com
Priti Kumar
CBR Institute of Biomedical Research, Harvard
800 Huntington Avenue, Room 213
Boston, MA 02115
kumar@cbr.med.harvard.edu
Venisetty Raj Kumar
Vaagdevi College of Pharmacy
H.No. 8-10-5, J.P.N. Road
Warangal, Andhra Pradesh, 506002, India
vrk102002@yahoo.co.in
Janel Lanphere
Boston Scientific Corporation
100 Boston Scientific Way
Marlborough, MA 01752
lanpherj@bsci.com
Kenneth Lau
Massachusetts Institute of Technology
77 Massachusetts Avenue, Room 66-259
Cambridge, MA 02139
klau@mit.edu
Afsaneh Lavasanifar
University of Alberta
4119 Faculty of Pharmacy &
Pharmaceutical Sciences
Edmonton, Alberta, T6G 2N8, Canada
alavasanifar@pharmacy.ualberta.ca
289
Preregistered Conferees
Roger Leblanc
University of Miami
Dept of Chemistry
1301 Memorial Drive
Cox Science Center
Coral Gables, FL 33146
rml@miami.edu
Hanchen P. Lee
Novartis Pharmaceuticals Corp.
One Health Plaza, Bldg 401
East Hanover, NJ 07936
hanchen.lee@pharma.novartis.com
Jaebeom Lee
University of Michigan
1930 Lindsay Lane
Ann Arbor, MI 48104
jaebomle@umich.edu
Jonghwi Lee
Chung-Ang University
221 Heukseok-dong, Dongjak-gu
Seoul, 156-756, Korea
jonghwi_lee@yahoo.co.kr
Priscilla Lee
Oregon Health & Science University
20000 NW Walker Road
Beaverton, OR 97006
leepr@ebs.ogi.edu
Robert J. Lee
The Ohio State University
College of Pharmacy
542 LM Parks Hall
500 West 12th Avenue
Columbus, OH 43210
lee.1339@osu.edu
Robert W. Lee
Novavax, Inc.
508 Lapp Road
Malvern, PA 19355
rlee@novavax.com
Sang-Kyung Lee
Hanyang University
Dept of Bioengineering
17 Haendang-dong, Seongdong-gu
Seoul, 133-791, Korea
sangkyunglee@hanyang.ac.kr
Yongwoo Lee
Foster-Miller, Inc.
195 Bear Hill
Waltham, MA 02451
ylee@foster-miller.com
290
Stephane Legastelois
Indicia Biotechnology
33 avenue de la California
Oullins, 69600, France
slegastelois@indicia.fr
Jeffrey Leon
Eastman Kodak Company
1999 Lake Avenue
Rochester, NY 14650-2116
jeffrey.leon@kodak.com
Dietmar Lerche
Dr. Lerche KG
Rudower Chaussee 29
12489, Berlin, Germany
office@lerche-biotec.com
Ingo Leubner
Crystallization Consulting
35 Hillcrest Drive
Penfield, NY 14526-2411
ileubner@crystallizationcon.com
Hans Leuenberger
Institute of Pharmaceutical Technology
Pharmacenter, Klingelbergstrasse 50
4056, Basel, Switzerland
hans.leuenberger@unibas.ch
Eik Leupold
Leibniz Institute of Molecular Pharmacology
Robert Rössle Strasse 10
13125 Berlin, Germany
leupold@fmp-berlin.de
Chun Li
U.T.M.D. Anderson Cancer Center
Dept of Experimental Diagnostic Imaging
1515 Holcombe Blvd
Houston, TX 77030
cli@di.mdacc.tmc.edu
Pauline Pei Li
The Hong Kong Polytechnic University
Applied Biology & Chemical Technology
Hung Hom
Kowloon, Hong Kong, 0000, China
bcpeili@polyu.edu.hk
Yongcheng Li
Vistakon, JNJ Vision Care
7500 Centurion Parkway
R&D Bldg, W1A
Jacksonville, FL 32256
yli5@visus.jnj.com
Preregistered Conferees
Yuzhuo Li
Clarkson University
Dept of Chemistry
8 Clarkson Avenue
Potsdam, NY 13699
yuzhuoli@clarkson.edu
Philip Low
Purdue University
Dept of Chemistry
560 Oval Drive
West Lafayette, IN 47907
plow@purdue.edu
Zhengmao Li
Bentley Pharmaceuticals, Inc.
2 Holland Way, Bentley Park
Exeter, NH 03833
zli@bentleypharm.com
Tao Lowe
Penn State University
The Milton S. Hershey Medical Center
500 University Drive
Hershey, PA 17033
tlowe@psu.edu
Ben Lich
FEI Company
5 Achtsteweg Noord
Eindhoven, 5600 KA, The Netherlands
blich@nl.feico.com
Victor S.-Y. Lin
Iowa State University
Dept of Chemistry
1710 Gilman Hall
Ames, IA 50011
vsylin@iastate.edu
Michael Lipp
Alkermes Inc.
88 Sidney Street
Cambridge, MA 02139
mike.lipp@alkermes.com
Jubo Liu
University of Toronto
19 Russell Street
Toronto, Ontario, M5S 2S2, Canada
jubo.liu@utoronto.ca
Tao Liu
Chinese Academy of Sciences
Institute of Chemistry
No. 2, Bei Yi Jie, Zhong Guan Cun
Beijing, He Bei, 100080, China
taoliu@iccas.ac.cn; leotao1974@yahoo.com
Andrew Loxley
Particle Sciences
3894 Courtney Street, Suite 180
Bethlehem, PA 18017
aloxley@particlesciences.com
Wei Lu
Fudan University
School of Pharmacy
138 Yi Xue Yuan Road, PO Box 130
Shanghai, 200032, China
wlu@fudan.edu.cn
Yi Lu
University of Illinois at Urbana-Champaign
Dept of Chemistry, MC-712, Box 8-6
600 South Mathews Avenue
Urbana, IL 61801
yi-lu@uiuc.edu
Thomas Luby
MGI PHARMA Biologics
44 Hartwell Avenue
Lexington, MA 02421
thomas.luby@mgipharma.com
Erik Lüddecke
BASF AG
Carl Bosch Strasse
67056 Ludwigshafen, Rheinland-Pfalz, Germany
erik.lueddecke@basf.com
Xiong Liu
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway, Suite 400
Orlando, FL 32826
xiongliu@mail.ucf.edu
Ananda Lugade
Luminex Corporation
12212 Technology Blvd
Austin, TX 78727
alugade@luminexcorp.com
Yan Liu
Arizona State University
Biodesign Institute, Box 875601
Tempe, AZ 85287
yan_liu@asu.edu
Dan Luo
Cornell University
226 Riley Robb
Ithaca, NY 14853
dl79@cornell.edu
291
Preregistered Conferees
Dongling Ma
National Research Council of Canada
100 Sussex Drive, Room 1045
Ottawa, Ontario, K1A 0R6, Canada
dongling.ma@nrc.ca
Sarina Harris Ma
Alza Corporation (J&J)
1010 Joaquin Road
Mountain View, CA 94043
sma8@alzus.jnj.com
Robert MacCuspie
Hunter College
Chemistry Dept
695 Park Avenue
New York, NY 10021
nano_rob@yahoo.com
Mizuo Maeda
Riken
2-1, Hirosawa
Wako, 351-0198, Japan
mizuo@riken.jp
Volker Mailänder
University of Ulm
Helmholtzstrasse 11
89075 Ulm, Germany
v.mailaender@blutspende.de
Wing Cheung Mak
National University of Singapore
Division of Bioengineering
9 Engineering Drive 1
Singapore, 117576, Singapore
biemwc@nus.edu.sg
Shlomo Margel
Bar-Ilan University
Dept of Chemistry
Ramat-Gan, 52900, Israel
shlomo.margel@mail.biu.ac.il
Peter Markland
Brookwood Pharmaceuticals
756 Tom Martin Drive
Birmingham, AL 35211
pmarkland@brookwoodpharma.com
Andrew Martin
University of Alberta
2-9 Mechanical Engineering Bldg
Edmonton, Alberta, T6G 2G8, Canada
armartin@ualberta.ca
Melanie Martin
Particles Conference
265 Clover Street
Rochester, NY 14610-2246
martin@nanoparticles.org
292
Sofia de Medina Aires Martins
Instituto Superior Técnico
Av. Rovisco Pais
Lisbon 1049-001, Portugal
sofiamartins@mail.ist.uti.pt
Yoshitake Masuda
Nagoya University
Furo-cho, Chikusa-ku
Nagoya, Aichi, 464-8603, Japan
masuda@apchem.nagoya-u.ac.jp
Terry Matsunaga
ImaRx Therapeutics, Inc.
1635 East 18th Street
Tucson, AZ 85719
tmatsunaga@imarx.com
Hedi Mattoussi
US Naval Research Laboratory
Optical Sciences Division
4555 Overlook Avenue, SW
Washington, DC 20375
hedimat@ccs.nrl.navy.mil
Shawn Mehrens
Pfizer Global R&D
2800 Plymouth Road
Ann Arbor, MI 48105
shawn.mehrens@pfizer.com
Anthony McGoron
Florida International University
10555 West Flagler Street
Miami, FL 33174
mcgoron@fiu.edu
James McGrath
University of Rochester
Biomedical Engineering
601 Elmwood Avenue
PO Box 639
Rochester, NY 14642
jmcgrath@bme.rochester.edu
Georges Meseguer
Swissmedic
Hallerstrasse 7
3000 Berne, Switzerland
georges.meseguer@swissmedic.ch
Mary Miller
MVA Scientific Consultants
3300 Breckinridge Blvd, Suite 400
Duluth, GA 30096
mmiller@mvainc.com
Preregistered Conferees
David Mines
Inotech Biosystems International
15713 Crabbs Branch Way
Rockville, MD 20855-2607
dmines@inotechintl.com
Rainer Müller
PharmaSol GmbH
Blohmstrasse 66A
12307 Berlin, Germany
mpharma@zedat.fu-berlin.de
Takashi Miyata
Kansai University
Faculty of Engineering
3-3-35, Yamate-cho
Suita, Osaka 564-8680, Japan
tmiyata@ipcku.kansai-u.ac.jp
Detlef Müller-Schulte
MagnaMedics GmbH
Martelenberger Weg 8
D-52066 Aachen, Germany
detlef.mueller2@post.rwth-aachen.de
Naomi Moldavski
Teva Pharmaceuticals Industries
R&D Initiative Dept
2 Hamerpe Street
Jerusalem 91010, Israel
naomi.moldavski@teva.co.il
Mike Morgen
Bend Research
64550 Research Road
Bend, OR 97701
morgen@bendres.com
Nobuyuki Morimoto
Tokyo Medical and Dental University
2-3-10 Kanda-surugadai
Chiyoda-ku, Tokyo 101-0062, Japan
mor.org@tmd.ac.jp
Shannon Morrison
Virginia Commonwealth University
Chemistry Dept
1001 West Main Street
Richmond, VA 23298
stuu@bluebottle.com
Brij Moudgil
University of Florida
205 PS&T Bldg
Gainesville, FL 32611
bmoudgil@erc.ufl.edu
Gerhard Muhrer
Novartis Pharmaceuticals Corp.
WSJ-145.11.51
4002 Basel, Switzerland
gerhard.muhrer@novartis.com
Angelika Müller
Charité Universitätsmedizin Berlin
Institut für Transfusionsmedizin
Schumannstrasse 20/21
10117 Berlin, Germany
angelica.mueller@charite.de
Shawn Mulvaney
Naval Research Laboratory
NRL – Code 6177
4555 Overlook Avenue SW
Washington, DC 20375
shawn.mulvaney@nrl.navy.mil
Matti Murtomaa
University of Turku
Dept of Physics
20014 Turku, Finland
matti.murtomaa@utu.fi
Anna Musyanovych
University of Ulm
Albert-Einstein-Allee 11
89081 Ulm, Germany
anna.musyanovych@uni-ulm.de
Maryanne Naath
Pfizer Inc.
295 Bud Lane
Northville, MI 48167
maryanne.naath@pfizer.com
Hiroyuki Nakamura
Gakushuin University
1-5-1, Mejiro, Toshima-ku
Tokyo, 171-8588, Japan
hiroyuki.nakamura@gakushuin.ac.jp
Michihiro Nakamura
The University of Tokushima Graduate School
3-18-15 Kuramoto-cho
Tokushima, 770-8503, Japan
michy@basic.med.tokushima-u.ac.jp
Yoshio Nakano
NOF Corporation
20-3, Ebisu 4-chome
Shibuya-ku
Tokyo, 150-6019, Japan
yoshio_nakano@nof.co.jp
Indranil Nandi
Sandoz
2400 Route 130 North
Dayton, NJ 08810
indranil.nandi@sandoz.com
293
Preregistered Conferees
Balaji Narasimhan
Iowa State University
Dept of Chemical and Biological Engineering
2035 Sweeney Hall
Ames, IA 50011
nbalaji@iastate.edu
Sudip Nath
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway
Orlando, FL 32826
snath@mail.ucf.edu
Laurence Navailles
Centre de Recherche Paul Pascal-CNRS
avenue A. Schweitzer
Pessac 33600, France
navailles@crpp-bordeaux.cnrs.fr
David Needham
Duke University
CIEMAS, Room 3391
Durham, NC 27708
d.needham@duke.edu
Boon Sing Ng
Stockholm University
Dept of Inorganic Chemistry
Arrhenius Laboratory
Stockholm 10691, Sweden
boonsing@inorg.su.se
Thor Nilsen
Genisphere
2801 Sterling Drive
Hatfield, PA 19440
thor_nilsen@datascope.com
Takasi Nisisako
The University of Tokyo
Graduate School of Engineering
7-3-1 Hongo, Bunkyo-ku
Tokyo, 113-8656, Japan
nisisako@intellect.pe.u-tokyo.ac.jp
Robert Nooney
Dublin City University
Biomedical Diagnostics Institute
Collins Avenue
Glasnevin, Dublin 9, Ireland
rno@physics.dcu.ie
Tim Norman
UCB Celltech
216 Bath Road
Slough, Berkshire, SL1 4EN, United Kingdom
tim.norman@ucb-group.com
294
Anika Odukale
University of Florida
314 Materials Engineering Bldg
PO Box 116400
Gainesville, FL 32611-6400
aodukale@ufl.edu
Teppei Ogata
Ono Pharmaceutical Corporation Ltd
3-1-1 Sakurai Shimamoto-cho
Mishima-gun
Osaka, 618-8585, Japan
t.ogata@ono.co.jp
Patrick O’Hagan
Particle Sizing Systems, Inc.
8203 Kristel Circle
Port Richey, FL 34668
pohagan@pssnicomp.com
Yosuke Okamura
Waseda University
Graduate School of Science & Engineering
3-4-1 Ohkubo, Shinjuku-ku
Tokyo, 169-8555, Japan
y.okamura@ruri.waseda.jp
Naoto Oku
University of Shizuoka
52-1, Yada, Suruga-ku
Shizuoka, 422-8526, Japan
oku@u-shizuoka-ken.ac.jp
Monika Oli
Banyan Biomarkers
12085 Research Drive
Alachua, FL 32615
moli@banyanbio.com
Anselmo Gomes de Oliveira
State of São Paulo University
Pharmacy School, Campus Universitario
Rodovia Araraquara-Jau km, 01
Araraquara, São Paulo, 14801-902, Brazil
oliveiag@fcfar.unesp.br
Tammy Oreskovic
National Institute of Standards and Technology
325 Broadway, MS 853
Boulder, CO 80305
oreskov@boulder.nist.gov
Sergei Ostapenko
University of South Florida
4202 East Fowler Avenue
Tampa, FL 33620
ostapenk@eng.usf.edu
Preregistered Conferees
Katsuto Otake
National Institute of Advanced Industrial Science
Higashi 1-1-1, Tsukuba Central 5
Tsukuba, Ibaraki 305-8565, Japan
katuotk@attglobal.net
John Otte
Novartis Pharmaceutical Corp.
One Health Plaza
Bldg 401, Room B184D
East Hanover, NJ 07936
john.otte@novartis.com
Jean Owens
Horiba Instruments, Inc.
1720 Peachtree Street, NW
Peachtree 25th Bldg, Suite 601
Atlanta, GA 30309
horibajowens@bellsouth.net
Giulio Paciotti
Cytimmune Sciences, Inc.
9640 Medical Center Drive
Rockville, MD 20850
support@cytimmune.com
Balaji Panchapakesan
University of Delaware
140 Evans Hall
Newark, DE 19716
baloo@ece.udel.edu
Wolfgang Parak
Ludwig Maximilians University-Munich
Center for Nanoscience
Amalienstrasse 54
80799 Munich, Germany
wolfgang.parak@physik.uni-muenchen.de
Chul Ho Park
Chung-Ang University
221 Heukseok-dong, Dongjak-gu
Seoul, 156-756, Korea
jonghwi_lee@yahoo.co.kr
Sang-Eun Park
Kyungwon University
San 65 Bockjung-dong, Soojung-gu
Seongnam-shi, Gyeonggi-do, 461-701, Korea
upsilver60@kyungwon.ac.kr
Sang-Im Park
Chungnam National University
220 Gung-dong, Yuseong-gu
Daejeon, 305-764, Korea
sipark@cnu.ac.kr
Andrew Parker
Molecular Profiles Ltd
Nottingham Business Park
8 Orchard Place
Nottingham, NG8 6PX, United Kingdom
aparker@molprofiles.co.uk
Robert Paull
Lux Capital
140 East 45th Street, 30th floor
New York, NY 10017
rpaull@luxcapital.com
Robert Pelton
McMaster University
1280 Main Street West
Hamilton, Ontario, L8S 4L7, Canada
peltonrh@mcmaster.ca
J. Manuel Perez
University of Central Florida
12424 Research Parkway, Suite 400
Orlando, FL 32826
jmperez@mail.ucf.edu
Denise F. S. Petri
Universidade de São Paulo
Av. Prof. Lineu Prestes 748
São Paulo, 05508-900, Brazil
dfsp@usp.br
Harald Petry
Berlex Biosciences
2600 Hilltop Drive
Richmond, CA 94804
harald_petry@berlex.com
Catherine Phelan
Moffitt Cancer Center
12902 Magnolia Drive
MRC-CANCONT
Tampa, FL 33612
phelancm@moffitt.usf.edu
Kathleen Pirollo
Georgetown University Medical Center
3970 Reservoir Road NW, TRB/E420
Washington, DC 20057-1469
pirollok@georgetown.edu
Michael Pishko
Penn State University
Dept of Chemical Engineering
204 Fenske Laboratory
University Park, PA 16802-4400
mpishko@engr.psu.edu
295
Preregistered Conferees
Michael Platscher
Merck Eprova AG
Im Laternenacker 5
8200 Schaffhausen, Switzerland
michael.platscher@eprova.com
Janne Raula
Helsinki University of Technology
Biologinkuja 7
Espoo, 02044, Finland
janne.raula@tkk.fi
Sara Ponce Marquez
University of Basque Country
Pharmacy and Pharmaceutical Technology
Paseo de la Universidad, 6
Vitoria, 01006, Spain
saraponcem@hotmail.com; knbpomas@vc.ehu.es
François Ravenelle
Labopharm Inc.
480 Armand Frappier
Laval, Quebec City, H7V 4B4, Canada
fravenelle@labopharm.com
Marc Porter
Iowa State University
42 Spedding Hall
Ames, IA 50011-3020
mporter@porter1.ameslab.gov
Jon Preece
University of Birmingham
School of Chemistry, Haworth Bldg
Edgbaston, Birmingham, B15 2TT
United Kingdom
j.a.preece@bham.ac.uk
Sheng Qi
University of East Anglia
School of Chemical Sciences & Pharmacy
Norwich, Norfolk, NR4 7TJ, United Kingdom
sheng.qi@uea.ac.uk
Haoyu Qin
Intel Corporation
2200 Mission College Blvd
Santa Clara, CA 95054
haoyu.qin@intel.com
Huihe Qiu
Hong Kong University of Science & Technology
Dept Mechanical Engineering
Clear Water Bay
Kowloon, Hong Kong, China
meqiu@ust.hk
Steve Rannard
Iota NanoSolutions
Merseybio, Crown Street
Liverpool, Merseyside, L69 7ZB
United Kingdom
steve.rannard@iotanano.com
Natalya Rapoport
University of Utah
20 South 2030 East, Room 108
Salt Lake City, UT 84112
natasha.rapoport@m.cc.utah.edu
296
Rick Rehrig
Harper International
West Drullard Avenue
Lancaster, NY 14086
rrehrig@harperintl.com
Andrew Riederer
Battelle Memorial Institute
505 King Avenue, 7-1-078
Columbus, OH 43201
riederera@battelle.org
Preston Rodenbaugh
CeloNova BioSciences, Inc.
49 Spring Street
Newnan, GA 30263
prodenbaugh@celonova.com
Philippe Rogueda
AstraZeneca R&D Charnwood
Bakewell Road
Loughborough, Leicestershire, LE11 5RH
United Kingdom
philippe.rogueda@astrazeneca.com
Edith Carolina Rojas
Tulane University
300 Lindy Boggs
New Orleans, LA 70118
erojas@tulane.edu
Sandra Rosenthal
Vanderbilt University
Box 1822, Station B
Nashville, TN 37235
sandra.j.rosenthal@vanderbilt.edu
Vincent Rotello
University of Massachusetts
Dept Chemistry
Amherst, MA 01003
rotello@chem.umass.edu
Ginger Denison Rothrock
Liquidia Technologies
PO Box 110085
Research Triangle Park, NC 27709
ginger.denison@liquidia.com
Preregistered Conferees
Luke Roush
Liquidia Technologies, Inc.
PO Box 110085
Research Triangle Park, NC 27709
luke.roush@liquidia.com
Isabella Sasso
Ryland Corporate Solutions
PO Box 2825
New York, NY 10017
sasso.isa@gmail.com
Paul Russo
Louisiana State University
1222 Louray Drive
Baton Rouge, LA 70808
chruss@lsu.edu
Reyad Sawafta
QuarTek Corporation
4180 Piedmont Parkway
Greensboro, NC 27410
rsawafta@quartekcorp.com
Kevin Ryan
Dow Corning Corporation
2200 West Salzburg Road
Midland, MI 48686
kevin.ryan@dowcorning.com
Curtis Sayre
Kimberly-Clark
1400 Holcomb Bridge Road
Roswell, GA 30076
curtis.sayre@kcc.com
Subir Sabui
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway
Orlando, FL 23826
ssubir2000@gmail.com
Jay Schild
Microtrac Inc.
nd
12501-A 62 Street North
Largo, FL 33773
jay_s@microtrac.com
Virginia Saez-Martinez
University of the Basque Country
Bo. Sarriena s/n
Leioa, Vizcaya, 48940, Spain
qfbsamav@ehu.es
Divey Saini
St. Louis University
3555 Vista Avenue, R405
St. Louis, MO 63111
sainid@slu.edu
Jarno Salonen
University of Turku
Dept Physics
Vesilinnantie
Turku, 20014, Finland
jarno.salonen@utu.fi
Niklas Sandler
University of Otago
School of Pharmacy
18 Fredrick Street
Dunedin 9001, New Zealand
niklas.sandler@stonebow.otago.ac.nz
Swadeshmukul Santra
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway, #400
Orlando, FL 32826
ssantra@mail.ucf.edu
Terrence Scott
Epic Therapeutics, Inc.
220 Norwood Park South
Norwood, MA 02062
terrence_scott@baxter.com
Satoshi Seino
Osaka University
2-1 Yamadaoka
Suita, Osaka, 565-0871, Japan
seino@mit.eng.osaka-u.ac.jp
Noboru Sekiya
Ono Pharmaceutical Corporation Ltd
3-1-1 Sakurai Shimamoto-cho
Mishima-gun
Osaka, 618 8585, Japan
sekiya@ono.co.jp
Boitumelo Semete
CSIR
Meiring Naude Road, Bldg 14C
Lynwood
Pretoria, Gauteng, 0002, South Africa
bsemete@csir.co.za
Kyung Do Seo
Hanyang University
17, Haengdang-dong, Seongdong-gu
Seoul, 133791, Korea
kdsuh@hanyang.ac.kr
Jun Shao
St. John’s University
8000 Utopia Parkway
Jamaica, NY 11439
shaoj@stjohns.edu
297
Preregistered Conferees
Jaswinder Sharma
Arizona State University
Biodesign Institute, Box 875601
Tempe, AZ 85287
jaswinder.sharma@asu.edu
Kenneth Smith
GlaxoSmithKline Pharmaceuticals
NFSP South Site
Third Avenue
Harlow, Essex, CM195AW
United Kingdom
kenneth.b.smith@gsk.com
David Sheff
University of Iowa
2-570-BSB
51 Newton Road
Iowa City, IA 52242
david-sheff@uiowa.edu
Herman Snyder
Nektar Therapeutics
150 Industrial Road
San Carlos, CA 94070
hsnyder@nektar.com
Boris Shekunov
Ferro Pfanstiehl Labs
7500 E. Pleasant Valley Road
Independence, OH 44131
shekunovb@ferro.com
Igor Sokolov
Clarkson University
6 Wellings Drive
Potsdam, NY 13676
isokolov@clarkson.edu
Robert Sievers
University of Colorado
Aktiv-Dry LLC
6060 Spine Road
Boulder, CO 80301
bob.sievers@colorado.edu
Ponisseril Somasundaran
Columbia University
Henry Krumb School
th
500 West 120 Street
New York, NY 10027
ps24@columbia.edu
Ravil Sitdikov
University of New Mexico
Chemical & Nuclear Engineering
MSC01-1120, 1 UNM
Albuquerque, NM 87131-0001
sitdikov@unm.edu
Ana Raquel Sousa
IBET
av da Republica, EAN, qta do Marque
Oeiras, 2781-901, Portugal
rsousa@itqb.unl.pt
Gary Slater
Eastman Kodak Company
Lake Avenue
Rochester, NY 14650
gary.slater@kodak.com
Lisa Slater
Eastman Kodak Company
Lake Avenue
Rochester, NY 14650
lisa.slater@kodak.com
Monique Smaïhi
CNRS-IEM UMR 5635
1919 route de Mende
34293 Montpellier Cedex 5, France
smaihi@iemm.univ-montp2.fr
Alex Smirnov
North Carolina State University
Dept Chemistry
Campus Box 8204
Raleigh, NC 27695-8204
alex_smirnov@ncsu.edu
298
Howard Stamato
Bristol-Myers Squibb
PO Box 191
New Brunswick, NJ 08903-0191
howard.stamato@bms.com
Natasha Starostina
Pacific Nanotechnology Inc.
17981 Sky Park Circle, Suite J
Irvine, CA 92614
nstarostina@pacificnanotech.com
Stefan Steigerwald
Sympatec Inc.
9 Princess Road, Suite A
Lawrenceville, NJ 08648
ssteigerwald@sympatec.com
Vicki Stone
Napier University
School of Life Sciences
Merchiston Campus
Edinburgh, EH10 5DT, United Kingdom
v.stone@napier.ac.uk
Preregistered Conferees
Julie Straub
Acusphere, Inc.
500 Arsenal Street
Watertown, MA 02472
julie.straub@acusphere.com
Jim Talton
Nanotherapeutics, Inc.
12085 Research Drive
Alachua, FL 32615
jtalt@nanotherapeutics.com
Sean Sullivan
University of Florida
Pharmaceutics Dept
Box 100494, JHMHC
1600 SW Archer Road
Gainesville, FL 32610
sullivan@cop.ufl.edu
Wee Beng Tan
National University of Singapore
Blk 723 Jurong West Avenue 5, #10-140
640723 Singapore
nnitwb@nus.edu.sg
Besik Surguladze
Center of Clinical Medicine
6/10 Baratashvili Str.
Tbilisi 0105, Georgia
ATT.BVS@ti.net.ge
Andreas Taubert
University of Basel
Dept Chemistry
Klingelbergstrasse 80
4056 Basel, Switzerland
andreas.taubert@unibas.ch
Sonke Svenson
Dendritic NanoTechnologies
2625 Denison Drive
Mount Pleasant, MI 48858
svenson@dnanotech.com
Wyatt Tenhaeff
Massachusetts Institute of Technology
Chemical Engineering
25 Ames Street, Room 66-419
Cambridge, MA 02129
tenhaeff@mit.edu
Hulda Swai
CSIR
Meiring Naude Road, Bldg 14C
Lynwood
Pretoria, Gauteng, 0002, South Africa
hswai@csir.co.za
John Texter
Eastern Michigan University
Coatings Research Institute
430 West Forest Avenue
Ypsilanti, MI 48197
jtexter@emich.edu
Janos Szebeni
Walter Reed Army Institute of Research
1600 East Gude Drive
Rockville, MD 20850
jszebeni@hivresearch.org
Nguyen Thi Kim Thanh
University of Liverpool
Dept Chemistry
Crown Street
Liverpool, L69 7ZD, United Kingdom
ntkthanh@liv.ac.uk
Francis Szoka
University of California at San Francisco
Depts Biopharmaceutical Sciences &
Pharmaceutical Chemistry
San Francisco, CA 94143-0446
szoka@cgl.ucsf.edu
Eriko Takeko
Sumitomo Chemical Co., Ltd.
2-1, Takatsukasa 4-chome
Takarzuka, Hyogo, 665-8555, Japan
isee@sc.sumitomo-chem.co.jp
Yashushi Takemura
Yokohama National University
79-5 Tokiwadai, Hodogaya
Yokohama, 240-8501, Japan
takemura@ynu.ac.jp
Dave Thomas
Brightwell Technologies Inc.
195 Stafford Road West
Ottawa, Ontario, K2H 9C1, Canada
dthomas@brightwelltech.com
David Thompson
Purdue University
Dept Chemistry
560 Oval Drive
West Lafayette, IN 47907
davethom@purdue.edu
Arjen Tinke
Johnson & Johnson Pharmaceutical R&D
Turnhoutseweg 30
Beerse, 2340, Belgium
atinke@prdbe.jnj.com
299
Preregistered Conferees
Giovana Radomille Tofoli
State University o fCampinas
Dept Biochemistry
Cidade Universitária Zeferino Vaz s/n
Campinas, SP, 13083-970, CP6109, Brazil
giovanatofoli@fop.unicamp.br
Ijeoma Uchegbu
University of Strathclyde
Pharmaceutical Science
27 Taylor Street
Glasgow, Scotland, G4 0NR, United Kingdom
i.f.uchegbu@strath.ac.uk
Maria Toler
Pfizer Inc.
7000 Portage Road
PORT-259-277
Kalamazoo, MI 49001
maria.r.toler@pfizer.com
Mohammad Shahab Uddin
National University of Singapore
Chemical & Biomolecular Engineering
4 Engineering Drive 4
117576 Singapore
cheshahb@nus.edu.sg
Vladimir Torchilin
Northeastern University
360 Huntington Avenue, Mugar R312
Boston, MA 02115
v.torchilin@neu.edu
Jasna Urbanija
University of Ljubljana
Faculty of Medicine
Lipiceva 2
1000 Ljubljana, Slovenia
jasna.urbanija@fe.uni-lj.si
Dieter Trau
National University of Singapore
9 Engineering Drive 1
117576 Singapore
bietrau@nus.edu.sg
Chi-Ming Tseng
3M Company
236-3A-01 3M Center
St. Paul, MN 55144
ctseng2@mmm.com
Robert Tshikhudo
University of Liverpool
Nanoscale Science Centre
Chemistry Dept, Oxford Street
Liverpool, NW, L73BX, United Kingdom
t.r.tshikhudo@liv.ac.uk
Bill Turnell
MediVas, LLC
6275 Nancy Ridge Drive
San Diego, CA 92121
bturnell@medivas.com
Hsien-Hsin Tung
Merck Company
PO Box 2000
Rahway, NJ 07065
hsien_hsin_tung@merck.com
Charlotta Turner
Uppsala University
Physical & Analytical Chemistry
PO Box 599
Uppsala, SE-75124, Sweden
charlotta.turner@kemi.uu.se
300
Martine Usdin
Médecins Sans Frontières
78, rue de Lausanne
PO Box 116
1211 Geneva 21, Switzerland
sarah.neerman@msf.geneva.com
Neal Vail
Southwest Research Institute
6220 Culebra
San Antonio, TX 78238
nvail@swri.org
Hubert van den Bergh
Swiss Federal Institute of Technology (EPFL)
LPAS – Station 6
1015 Lausanne, Switzerland
hubert.vandenbergh@epfl.ch
Cornelus van Nostrum
Utrecht University
Dept Pharmaceutics
Sorbonnelaan 16
3584 CA Utrecht, The Netherlands
c.f.vannostrum@pharm.uu.nl
Tinneke Van Thienen
University Ghent
Lab General Biochemistry &
Physical Pharmacy
Harelbekestraat 72
B-9000 Ghent, Belgium
tinneke.vanthienen@ugent.be
Frank van Veggel
University of Victoria
Dept Chemistry
PO Box 3065
Victoria, BC, V8W 3V6, Canada
fvv@uvic.ca
Preregistered Conferees
Tim Vander Wood
MVA Scientific Consultants
3300 Breckinridge Blvd, #400
Duluth, GA 30096
tvanderwood@mvainc.com
Natalia Varaksa
National Institute of Standards
and Technology
325 Broadway Street
Boulder, CO 80305
varaksa@boulder.nist.gov
Sebastein Vasseur
University of Bordeaux
Institute of Condensed Matter
Chemistry (ICMCB)
87 ave Dr. Schweitzer
33608 Pessac Cedex, France
vasseur@icmcb-bordeaux.cnrs.fr
Omid Veiseh
University of Washington
Materials Science & Engineering
Box 352120
Kirkland, WA 98195-2120
omid@u.washington.edu
Orlin Velev
North Carolina State University
Chemical & Biomolecular Engineering
EB 1.911 Partners Way
Raleigh, NC 27695-7905
odvelev@unity.ncsu.edu
Krassimir Velikov
Unilever R&D Vlaardingen
Olivier van Noortlaan 120
Vlaardingen, 3133 AT, The Netherlands
krassimir.velikov@unilever.com
Geert Verreck
Johnson & Johnson
Pharmaceutical R&D
Turnhoutseweg 30
2340 Beerse, Belgium
gverreck@prdbe.jnj.com
Brigitte von Rechenberg
University of Zurich
Equine Hospital
Musculoskeletal Research Unit
Winterthurerstrasse 260
8057 Zurich, Switzerland
bvonrechenberg@vetclinics.unizh.ch
Tania Vu
Oregon Health & Sciences University
Biomedical Engineering
20000 NW Walker Road
Beaverton, OR 97006-8921
tvu@bme.ogi.edu
Amy Waligorski
Chemimage
7301 Penn Avenue
Pittsburgh, PA 15208
waligorskia@chemimage.com
Jinping Wan
Guidant Corp.
3200 Lakeside Drive
Santa Clara, CA 95054
jwan@guidant.com
Qiangbin Wang
Arizona State University
Chemistry & Biochemistry
Tempe, AZ 85287-1604
qiangbin.wang@asu.edu
Changchun Wang
Fudan University
Micromolecular Science
Shanghai 200433, China
ccwang@fudan.edu.cn
Weimin Wang
Sirna Therapeutics, Inc.
2950 Wilderness Place
Boulder, CO 80301
wangw@sirna.com
Yongxian Wang
Chinese Academy of Sciences
Shanghai Institute of Applied Physics
No. 2019 Jialuo Road
Jiading, Shanghai 201800, China
yongxianw@163.com
Kevin Ward
Alkermes, Inc.
88 Sidney Street
Cambridge, MA 02139
kevin.ward@alkermes.com
Clive Washington
AstraZeneca
PU6, Lab Block
Silk Road Business Park
Maclesfield, Cheshire, SK10 2NA
United Kingdom
clive.washington@astrazeneca.com
301
Preregistered Conferees
Drew Wassel
Hough Ear Institute
3400 NW 56 Street
Oklahoma City, OK 73112
drewwassel@gmail.com
Daniel Watts
New Jersey Institute of Technology
Otto York Center for Environmental
Engineering & Science
323 Martin Luther King Blvd
Newark, NJ 07102
watts@njit.edu
Wolfgang Weber
LUM Corporation
200 Boston Avenue, Suite 2900
Medford, MA 02155
wolfgang@lumanalytical.com
Karsten Wegner
Swiss Federal Institute of Technology
ETH Zentrum ML F22
Sonneggstrasse 3
CH-8092 Zurich, Switzerland
wegner@ptl.mavt.ethz.ch
Janet Wendorf
Novartis Vaccines & Diagnostics
4560 Horton Street, M/S 4.3
Emeryville, CA 94530
janet_wendorf@chiron.com
Per Wessman
Uppsala University
Physical & Analytical Chemistry
Box 579
SE-75123 Uppsala, Sweden
per.wessman@fki.uu.se
Anthony West
Innovata plc
One Mere Way
Ruddington, Nottinghamshire NG11 6JS
United Kingdom
awest@innovataplc.com
Nicola Whitfield
Innovata plc
One Mere Way
Ruddington, Nottinghamshire NG11 6JS
United Kingdom
nwhitfield@innovataplc.com
P. Stephen Williams
Cleveland Clinic
Biomedical Engineering
9500 Euclid Avenue
Cleveland, OH 44195
willias3@ccf.org
302
Roel Wirix-Speetjens
IMEC
MCP NEXT-ART
Kapeldreef 75
3001 Heverlee-Leuven, Belgium
wirixsp@imec.be
Martin Woodle
Intradigm Corp.
12115 K Parklawn Drive
Rockville, MD 20852
mwoodle@intradigm.com
James Worden
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway, Suite 400
Orlando, FL 32826
pkrfan@gmail.com
Shirley X.Y. Wu
University of Toronto
19 Russell Street
Toronto, Ontario, M5S 2S2, Canada
xywu@phm.utoronto.ca
Yi Wu
Pfizer Inc.
10646 Science Center Drive (CB4)
San Diego, CA 92121
grace.wu@pfizer.com
Zemin Wu
Starpharma
75 Commercial Road
Melbourne, Victoria, 3004, Australia
zemin.wu@starpharma.com
Shy Chyi Wuang
National University of Singapore
Chemical & Biomolecular Engineering
4 Engineering Drive 4, E5 04-07
117576 Singapore
g0403162@nus.edu.sg
Tian-Xiang Xiang
University of Kentucky
College of Pharmacy
725 Rose Street, Room 501
Lexington, KY 40536-0082
kharvey@email.uky.edu
Hiroshi Yamakose
Sankyo Co., Ltd.
1-2-58 Hiromachi, Shinagawa-ku
Tokyo 140-8710, Japan
hyamak@sankyo.co.jp
Preregistered Conferees
Yuichi Yamasaki
The University of Tokyo
7-3-1 Hongo
Bunkyo, Tokyo 113-8656, Japan
yamasaki@bmw.t.u-tokyo.ac.jp
Hong Yang
University of Rochester
Chemical Engineering
206 Gavett Hall
Rochester, NY 14627
hongyang@che.rochester.edu
Xiqiang Yang
Eastman Kodak Company
Lake Avenue
Rochester, NY 14650
xiqiang.yang@kodak.com
Matthew Yates
University of Rochester
Chemical Engineering
Rochester, NY 14627
myates@che.rochester.edu
Ji Youn Yoo
Chung-ang University
221 Heukseok-dong, Dongjak-gu
Seoul 156-756, Korea
jonghwi_lee@yahoo.co.kr
Hidekazu Yoshizawa
Okayama University
3-1-1 Tsushima-Higashi
Okayama 700-8530, Japan
yhide@cc.okayama-u.ac.jp
Ji-Hun Yu
Korea Institute of Machinery & Materials
66 Sangnam
Changwon, Gyeongnam 641-010, Korea
jhyu01@kmail.kimm.re.kr
Kui Yu
National Research Council of Canada
100 Sussex Drive
Ottawa, Ontario, K1A 0R6, Canada
kui.yu@nrc.ca
Jimmy Yun
NanoMaterials Technology Pte Ltd
28 Ayer Rajah Crescent #03-03
139959 Singapore
jimmy.yun@nanomt.com
Aleksandra Zajak
Moffitt Cancer Center
12902 Magnolia Drive
MRC-Cancont
Tampa, FL 33612
zajaca@moffitt.usf.edu
Guifang Zhang
University of Minnesota
308 Harvard St SE, 9-177 WDH
Minneapolis, MN 55455
zhang337@umn.edu
Huixiang Zhang
Alcon Research Ltd
6201 South Freeway R1-26
Fort Worth, TX 76134
huixiang.zhang@alconlabs.com
Jin Zhang
University of California at Santa Cruz
Dept Chemistry
156 High Street
Santa Cruz, CA 95064
zhang@chemistry.ucsc.edu
Shi-Wei Zhang
Saoirse Corporation
300 Technology Square
Cambridge, MA 02139
szhang@saoirse.com
Shiying Zheng
Eastman Kodak Company
1999 Lake Avenue
Rochester, NY 14530
shiying.zheng@kodak.com
Tao Zheng
Avon Products, Inc.
One Avon Place
Suffern, NY 10901
tao.zheng@avon.com
Tatyana Zhukov
Moffitt Cancer Center
12902 Magnolia Drive
MRC-Cancont
Tampa, FL 33612
zhukovta@moffitt.usf.edu
Jianhua Zou
University of Central Florida
Nanoscience Technology Center
12424 Research Parkway, 4th fl.
Orlando, FL 32826
jhzou1979@yahoo.com
Louis Zumstein
Introgen Therapeutics
2250 Holcombe Blvd
Houston, TX 77030
l.zumstein@introgen.com
303
Notes
304
Notes
305
Notes
306
Notes
307
Notes
308
309
Receipt
This receipt acknowledges payment of _______________________
from __________________________________________________ by
____________________________________________________ for
the conference registration fee for Particles 2006 held 13-16 May 2006 at
the Wyndham Resort Hotel, Orlando, Florida, USA
________________________________________________
On behalf of:
Particles Conference
265 Clover Street
Rochester, NY 14610-2246, USA
EIN No. 16-1565388
Tel: 1-585-288-5913
Fax: 1-585-482-7795
310