NanoRelease
Task Group 1: Material Characteristics
Characteristics Relevant to Uptake and
Bioavailability
www.riskscience.org
1
TG1: Material Characteristics
CHARGE
• Provide overview of physical
and chemical attributes of
nanoparticles that may affect
their uptake in the alimentary
tract.
• Provide overview of physical
and chemical attributes of
the food matrix that may
affect nanoparticle uptake in
the alimentary tract.
www.riskscience.org
2
Task Group 1: Sub-Groups
Task Group 1
Material Characteristics
Sub-Group 1 - What is (may be) in the food chain
Sub-Group 2 – Nanomaterial properties
Matrix interactions
relevant to uptake
& bioaccessibility
www.riskscience.org
3
TG1 Members
Sub-Group 1: ‘Catalogue’
Sub-Group 2: ‘Particle Properties’
CHAIR Scott Thurmond US FDA
CHAIR Rickey Yada University of Guelph
Tim Duncan US FDA
CHAIR Neil Buck DSM Ltd
Greg Noonan US FDA (CFSAN)
Gemma Janer Leitat Technological Center
Jeff Yourick US FDA (OARSA)
Prabir Dutta Ohio State University
Jamie Oxley Southwest Research Institute
Cristina Sabliov Louisiana State University and LSU AgCenter
Iseult Lynch University College Dublin
Additional involved
members/advisors:
Anil Patri (US NIH), Jun
Jie Yin (US FDA), Kevin
Powers (U. of Florida),
Lekh Juneja (Taiyo
Kagaku Co, Japan), Sean
Linder (US FDA), Il Je Yu
(Hoseo University, S.
Korea), Jonathan Powell
(MRC Human Nutrition
Research)
Karen Tiede The (UK) Food & Environment Research Agency
Julian McClements University of Massachusetts
Chris DeMerlis ColorCon Inc.
Andy Rao Cornell Food Science
Michael Rogers Rutgers University
Mengshi Lin University of Missouri
Qingrong Huang Rutgers University
Qixin Zhong University of Tennessee
Yuan Yao Purdue University
www.riskscience.org
4
Sub-Group 1: Catalogue
Purpose of the Nanomaterial Catalogue
• Review of ENM that are purportedly in internationally marketed food products
• Provide “real time” input to NanoRelease task groups to support identification
and development of analytical detection and characterization methods
on nanomaterials used in commerce.
Collection methods
Resources:
• FoodEssentials LabelBase, Gladson Nutrition database, Mintel Global New
Products database
• U. S. Patent and Trademark Office and European Patent Office databases
• Project on Emerging Nanotechnologies consumer inventory
• Published literature and business press
• Threshold® professional literature/patent search firm
• Regional sources
www.riskscience.org
5
Sub-Group 1: Catalogue
Results
Nanomaterial
Products
Origin
www.riskscience.org
6
Sub-Group 1: Catalogue
Summary
• Catalogue is just a snapshot of what may be on the international market.
• Two nanomaterials, calcium and silver, predominate, although nano-calcium was
found only in Asia.
• Supplements (nutritional and dietary) dominate the product classes for the
incorporation of nanomaterials.
Conclusions
• Lack of labeling requirements in most countries make compilation of a
comprehensive catalogue difficult.
• Although this snapshot is focused primarily on North America and Asia, we feel
that it may be representative of food-related nanoproducts found in other regions
of the world.
• Without analytical data for the identified nanoproducts, it is impossible to confirm
that they contain nanomaterials.
www.riskscience.org
7
Sub-Group 1: Catalogue
NanoMaterials known to be present in the food chain
www.riskscience.org
8
Sub-Group 2: Material Characteristics
www.riskscience.org
9
Sub-Group 2: Material Characteristics
Particles
Metals and metalloids
Polymeric encapsulates
Emulsions, Dispersions and Powders Thereof
www.riskscience.org
10
General properties of interest
Chou, L. Y. T, K. Ming
and W. C. W. Chan.
Chem. Soc. Rev. 2011,
40, 233-245.
www.riskscience.org
11
Digestive Processes & Food Interaction
Sub-Group 2: Material Characteristics
Nano Form Materials
Physical Change
Mucus Epithelium
Vasculature &
Local tissues
lymphatics
Transcellular
Paracellular
Persorption
Disruption to molecular
components
Sequestration &
elimination
Cytosis & accumulation
www.riskscience.org
12
Sub-Group 2: Material Characteristics
Metals and Metalloids
Definition and Usage:
• Metal and metalloid particles in food are used for a wide range of applications: nutrients,
colour additives, flow agents, food contact materials. Their nano-size may be intentional
(e.g., to improve functionality as in the absorption of nutrients) or unintentional (portion of a
particle population above the nano range).
Requirements for Characterisation:
• Concentration and chemical composition (core and surface)
• Primary size (and surface are), shape, and aggregation/agglomeration/exfoliation state.
• Surface charge
Uncertainties:
• Most relevant concentration units
• At which point NM should be characterized. Prior to inclusion in food matrix, in the food
matrix, in contact with gastrointestinal fluids…
www.riskscience.org
13
Sub-Group 2: Material Characteristics
Metals and Metalloids
Analytical Gaps and Difficulties:
• How to extract nanomaterials from food matrices without altering their properties, such
as aggregation/agglomeration/exfoliation state.
• Quantitative method for metal content exist (e.g., ICP-MS) but do not inform on the
properties of the material (size, shape, surface coating).
• Methods that allow the evaluation of size, shape, and aggregation state (e.g., TEM,
RAMAN) are not quantitative, low throughput and expensive.
Matrix Interactions:
• Food matrices may affect the properties (and ultimately uptake) of nanomaterials, by changing
their aggregation/agglomeration/exfoliation state, by changing their surface properties (by
coating them), and when considering relatively soluble nanomaterials by determining their
dissolution rate into ions.
• Nanomaterials can also change the food matrix by modifying the bioavailability of some
nutrients or chemically modifying them.
www.riskscience.org
14
Sub-Group 2: Material Characteristics
Polymeric Encapsulates
Definition and Usage
Polymeric nanoparticles with a typical size range of 20-1000 nm formed by a polymeric
core, with the active component entrapped in the polymeric matrix, usually surrounded
by a surfactant layer that stabilizes the system.
Requirements for Characterisation
Size, zeta potential, morphology, hydrophobicity, solubility, stability, degradation
Uncertainties
GI fate, nanoparticle degradation, uptake through the gut, biodistribution, metabolism,
excretion, toxicity
Analytical Gaps and Difficulties
Nanoparticle-food matrix interaction, nanoparticle tracing in the gut and in the body
Matrix Interactions
Largely unknown
www.riskscience.org
15
Sub-Group 2: Material Characteristics
Emulsions, Dispersions & Powders Thereof
Definition and Usage
Preparations of water-immiscible nutrients and additives, designed for stabilisation, ease of
handling, delivery or organoleptic properties. Various preparation methods for emulsions and
dispersions in water are available, powder production involves the use of soluble biopolymer and
spray-drying or other similar method.
Requirements for Characterisation
•
•
•
Digestibility
Particle size distribution
Composition & Charge
Uncertainties
Whether there is direct absorption from the GI tract, thus circumventing normal physiological
digestion.
Analytical Gaps and Difficulties
•
•
Sample preparation: what to model (as produced, as used, as prepared, GI environment)
Representative number-size distribution, lack of analytical methods suitable for emulsions
Matrix Interactions
Exacerbation of the above due to interference from complex matricies
‘Black box’ …..
www.riskscience.org
16
Summary
Requirement
Key Points
Difficulty
Composition
-
-
Surface physico-chemistry
In what environment
Multiple-steps
Morphological aspects
Where in the food-chain to
characterise
Multiple-steps
Size (incl agglo/aggre)
Appropriate unit
Method to suit appropriate
unit
‘Sample prep’
Preparation causes change
Shape
May not be homogeneous
quantification
Digestability
Qualification &
quantification of direct
uptake?
All of the above
www.riskscience.org
17
Conclusion
o As far as can be ascertained current ‘nano-sized’ ingredients are minerals,
silver and new nutrient/additive preparations.
o Silver, ceramics and clays are used in contact materials.
o List of required measurands is limited.
o However, almost all measurands present difficulty:
 what product stage should be considered?
• matrix effects are mostly unknown.
 what method(s) is suitable for sample preparation and analysis?
www.riskscience.org
18
Conclusion
As
manufactured
As formulated
As prepared
As eaten
As passaged in
GI
www.riskscience.org
19