Biomimetic microsystem for the generation
and detection of ratiometrically encoded
semiochemicals
Z. Racz, M. Cole. J.W. Gardner, S. Pathak
University of Warwick, United Kingdom
H. Gardeniers, W. Bula, N. Dimov
MESA+ Institute for Nanotechnology, Netherlands
D. Markovic, J. Challiss
University of Leicester, United Kingdom
5/31/2016
1 Session, 16 Sept. 2009
UKSN, iCHEM
Contents
• Fundamentals of Surface Acoustic Waves
• Chemoemission
• Atomization by acoustic waves
• Emission by micromachined device
• Wind tunnel results
• Chemodetection
• Detection by quartz crystal microbalance
• Detection by SAW device
• Outlook and applications
5/31/2016
2 Session, 16 Sept. 2009
UKSN, iCHEM
Fundamentals of Surface Acoustic Waves
Piezoelectric and reverse piezoelectric effect
Electric potential is generated in
response to mechanical stress
Mechanical deformation occurs
when electric field is applied
Surface acoustic wave generation using periodic electrodes
IDT spacing
Gold electrode
Periodic alternating
potential creates acoustic
surface wave
Piezoelectric substrate
5/31/2016
3 Session, 16 Sept. 2009
UKSN, iCHEM
Particle emission with piezoelectric-atomizer
Pheromone container
Piezoelectric aerosol nozzle
Control circuit
3 mm
5/31/2016
4 Session, 16 Sept. 2009
UKSN, iCHEM
Control of odorant droplet size
Estimated droplet diameter for water:
f [Hz] 50k 100k 500k 1M 3M
5M
10M
d [µm] 22.5 14.2
1.0
0.7
4.8
3.0
1.5
Droplet diameter [um]
25
20
15
10
5
0
0
5/31/2016
1
2
3
Atomizer frequency [MHz]
4
5
Droplet size can be
controlled by frequency but
wetting properties must be
designed carefully
5 Session, 16 Sept. 2009
UKSN, iCHEM
LabVIEW interface
USB data acquisition unit
141 kHz square wave
Ni/Co membranes on generator
piezoelectric atomizers CMOS analog switch
Microcontroller
5/31/2016
6 Session, 16 Sept. 2009
UKSN, iCHEM
Atomization by Surface Acoustic Waves
M. Alvarez et. al. Nanotechnology 19 (2008)
K. Chono et. al. IEEE Ultrasonics Symposium (2003)
5/31/2016
Provides three modes of particle
generation but frequency is fixed
7 Session, 16 Sept. 2009
UKSN, iCHEM
Micromachined device for ligand emission:
Artificial gland
• Evaporation drives emission
• Rate of emission controlled by surface morphology and temperature
Cuticular hairs of
Helicoverpa zea, showing
droplets of extraction
(Raina et al., 2000)
5/31/2016
Porous silicon
Black silicon
8 Session, 16 Sept. 2009
UKSN, iCHEM
Second generation of Artificial gland for
integration with biosynthetic microreactor
to micro reactor
heaters
membrane
biomimic: black silicon surface
membrane has tuned wettability
5/31/2016
9 Session, 16 Sept. 2009
UKSN, iCHEM
Artificial gland – fabrication results
Chip size:
20 mm x 15 mm
5/31/2016
10 Session, 16 Sept. 2009
UKSN, iCHEM
Ligand selection: Fruit volatiles and pheromones
Apple
Hawthorn
Dogwood
Chemical
butyl hexanoate
pentyl hexanoate
propyl hexanoate
butyl butanoate
hexyl butanoate
butyl hexanoate
3-methylbutan-1-ol
isoamyl acetate
4,8-dimethyl-1,3(E),7-nonatriene
ethyl acetate
dihydro--ionone
-caryophyllene
3-methylbutan-1-ol
isoamyl acetate
1-octen-3-ol
ethyl acetate
dimethyl trisulfide
GC (%)
37
5
4
10
44
0.01
4
1.5
0.09
94.3
0.10
5.8
27.5
0.9
9
54.9
1.9
(Linn et. al, 2005)
5/31/2016
11 Session, 16 Sept. 2009
UKSN, iCHEM
Ligand transfer – Volatile fluid dynamics
• Wind tunnel experiments for
evaporation rates and detection limits
(Dr. Carot)
• Mini-scale wind tunnel: odour chamber
Computer interface
Odour chamber
Inlet ports
Sensor array
5/31/2016
12 Session, 16 Sept. 2009
UKSN, iCHEM
Detection: Quartz crystal microbalances (QCMs)
Frequency shift due to mass change:
f  
2f
2
0
A q q
m f Sauerbrey equation
Sensitivity: ∆f = 7.2 Hz/ng
Gas sensitive
coating
AC
Gold
electrode
Quartz
crystal
Gold
electrode
5/31/2016
3 mm
13 Session, 16 Sept. 2009
UKSN, iCHEM
Ligand detection using QCMs
3. seq.
2. seq.
1. seq.
Odorant
3m
HB
EA
BH
BH
HB
EA
3m
3m
HB
BH
EA
PSF
137
127
136
134
59
98
157
90
80
82
69
130
PSB
144
103
57
87
77
127
28
39
39
138
118
33
PEG
110
58
35
33
26
31
59
46
49
57
53
31
PMMA
42
29
28
32
15
14
26
18
16
24
22
22
4
DF2: 30.9%
3m
0
-2
BH
HB
-4
-4
5/31/2016
EA
2
-2
0
2
DF1: 40.3%
4
6
14 Session, 16 Sept. 2009
UKSN, iCHEM
Blend Coding for Fruit Components
3:1
1:1
1:3
Plots showing the concept of ratiometric coding using two chemical
components (a) and the target results of such an experiment (b).
5/31/2016
15 Session, 16 Sept. 2009
UKSN, iCHEM
Output from first prototype system
Frequency change of PCL coated QCM vs. Frequency change of PSB coated QCM in
response to a randomized sequence of 36 injections of an ethyl acetate/3-methylbutan-1ol mixture of varying concentration and mixing ratio
5/31/2016
16 Session, 16 Sept. 2009
UKSN, iCHEM
Detection II: SAW Delay Line Device
Similar principle of operation as QCMs:
Input IDT
Output IDT
Launched surface wave
Sensing area
Piezoelectric substrate
Output: attenuation and phase
a)
5/31/2016
f v  f p cv K /  p
• Very sensitive to mechanical
and electrical perturbations
• Simple, robust design
• Uniform sensing area
• Large sensing area
b)
17 Session, 16 Sept. 2009
UKSN, iCHEM
Principle of SAW bio-probe
25 MHz SAW
penetrates yeast cells
Nucleus
PDL
Bilipid layer
Cell edge
5 GHz SAW penetrates
10 nm coating
LiTaO3 substrate
Poly-D-lysine
Thickness Frequency Feature size
ardb.bjmu.edu.cn
[nm]
[MHz]
[nm]
15
39,901
26 GHz for GPCR or antibodies
Bilipid layer
22.5
26,600
39
Edge of cell
615
973
1,069
7,515
80
13,064
15,015
40
26,102
Middle of cell
Upright cell
5/31/2016
www.bio.miami.edu
www.unm.edu
18 Session, 16 Sept. 2009
UKSN, iCHEM
Dual SAW biosensor output
Cell + OR22a + ligand
Cell + ligand
SAW sensor
=
SAW sensor
FREE DUAL SAWs
 fOR22a  f 0    ( cell ,  r , mcell , cell ,...)
SHORTED DUAL SAWs
 f OR22a 
5/31/2016
f 0    (mcell , cell ,...)
19 Session, 16 Sept. 2009
UKSN, iCHEM
Simplified Artificial Antennal Lobe!
Cell + OR22a + ligand
Cell + ligand
SAW sensor
Cell + OR67d + ligand
Cell + ligand
SAW sensor
Cell + OR83b + ligand
SAW sensor
Cell + ligand
SAW sensor
5/31/2016
FPGA with neuromorphic model
SAW sensor
Interface circuitry
-
SAW sensor
20 Session, 16 Sept. 2009
UKSN, iCHEM
HEK cell coated SAW sensors
Cell deposition
SAW device
Liquid chamber
HEK cells on SAW device
HEK cells on SAW device
20 μm
5/31/2016
2.5 μm
21 Session, 16 Sept. 2009
UKSN, iCHEM
Biosensor characterization setup
Real time cell
monitoring
SAW Sensor with
HEK293 cells
Optical
Microscope
Network
Analyser
Dry-Block Heater
for Temperature
Control
5/31/2016
22 Session, 16 Sept. 2009
UKSN, iCHEM
Prototype Infochemical System
QCM interface
Receiver
Emitter
Gland
interface
Pump
5/31/2016
23 Session, 16 Sept. 2009
UKSN, iCHEM
Summary
• Piezoelectric chemoemitter and microevaporator presented
• Cell based piezoelectric chemodetector with
insect ORs designed
• Prototype infochemical system shown
• Ratiometrically encoded food volatiles
discussed
• Pheromone bioreactor under construction
5/31/2016
24 Session, 16 Sept. 2009
UKSN, iCHEM
Outlook
• Integrate artificial gland and
biosensors into CMOS compatible
microsystem
• Real world applications:
• platform to explore semiochemistry)
• insect semiochemistry (interference
with insect communication, crop
protection)
5/31/2016
25 Session, 16 Sept. 2009
UKSN, iCHEM
Acknowledgements
• Financial support from EU FP6 FET programme
– iCHEM project
• See: www.warwick.ac.uk/go/iCHEM
5/31/2016
26 Session, 16 Sept. 2009
UKSN, iCHEM