nanorelease task group 1: material characteristics characteristics relevant to uptake and...
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NanoRelease Task Group 1: Material Characteristics
Characteristics Relevant to Uptake and Bioavailability
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TG1: Material CharacteristicsCHARGE
• 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.
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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
Task Group 1: Sub-Groups
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CHAIR Scott Thurmond US FDA
Tim Duncan US FDA
Greg Noonan US FDA (CFSAN)
Jeff Yourick US FDA (OARSA)
CHAIR Rickey Yada University of Guelph
CHAIR Neil Buck DSM Ltd
Gemma Janer Leitat Technological Center
Prabir Dutta Ohio State University
Jamie Oxley Southwest Research Institute
Cristina Sabliov Louisiana State University and LSU AgCenter
Iseult Lynch University College Dublin
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
TG1 MembersSub-Group 1: ‘Catalogue’ Sub-Group 2: ‘Particle Properties’
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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)
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 methodson 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
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Sub-Group 1: CatalogueResults
Nanomaterial Products Origin
Calcium Primarily dairy/soy (e.g. yogurts, supplemented milk, etc.)
Various Asian countries
Silver Dietary supplements NA, Oceania
Titanium dioxide, silver, clay, ceramics
Food contact materials
NA, Europe, Asia
Nanocapsules (liposomes, micelles, cyclodextrin, etc.)
Dietary/nutritional supplements
NA, Europe
Mineral supplements
Various minerals (other than calcium)
NA, Asia,
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.
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Sub-Group 1: CatalogueNanoMaterials known to be present in the food chain
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Sub-Group 2: Material Characteristics
ParticlesMetals and metalloidsPolymeric encapsulates
Emulsions, Dispersions and Powders Thereof
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Chou, L. Y. T, K. Ming and W. C. W. Chan. Chem. Soc. Rev. 2011, 40, 233-245.
General properties of interest
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Mucus EpitheliumVasculature &
lymphatics Local tissues
Paracellular
Persorption
Transcellular
Nano Form Materials
Physical Change
Disruption to molecular components
Cytosis & accumulationSequestration &
eliminationDig
estiv
e Pr
oces
ses
& F
ood
Inte
racti
onSub-Group 2: Material Characteristics
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Sub-Group 2: Material CharacteristicsMetals 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…
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Sub-Group 2: Material CharacteristicsMetals 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.
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Sub-Group 2: Material CharacteristicsPolymeric Encapsulates
Definition and UsagePolymeric 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 CharacterisationSize, zeta potential, morphology, hydrophobicity, solubility, stability, degradation
Analytical Gaps and DifficultiesNanoparticle-food matrix interaction, nanoparticle tracing in the gut and in the bodyMatrix InteractionsLargely unknown
UncertaintiesGI fate, nanoparticle degradation, uptake through the gut, biodistribution, metabolism, excretion, toxicity
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Sub-Group 2: Material CharacteristicsEmulsions, Dispersions & Powders Thereof
Definition and UsagePreparations 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
UncertaintiesWhether 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 InteractionsExacerbation of the above due to interference from complex matricies‘Black box’ …..
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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
Summary
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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?
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Conclusion
As formulated
As manufactured
As prepared
As eaten
As passaged in GI
Ease of Analysis
Matrix Complexity
Matrix Diversity
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