Nanocrystalline Cellulose: International Standardization & Metrological Approaches Alan Steele National Research Council Institute for National Measurement Standards TAPPI International Conference on Nano for Renewable Materials Workshop on International Standards June 9, 2011
Nanotechnology What is it? SI Unit of Length: 1 nm = 10-9 m Atomic sizes and lattice spacings are smaller particle ~ 10 fm neutral He atom ~ 30 pm neutral Fe atom ~ 150 pm lattice ~ 0.2 nm to 0.8 nm Biological size range proteins ~ 1 to 10 nm DNA radius ~ 2.5 nm viruses ~ 10 to 100 nm cells ~ 1 μm to 100 μm
Policy, Standards and Metrology Many countries are participating in international development of policy, standards and metrology for nanotechnologies through established channels and organizations
OECD : Intergovernmental Policy Organisation for Economic Cooperation and Development governmental organization working to ensure that that potential safety issues are being addressed at the same time as nanotechnology is developing Working Party on Nanotechnology advising on emerging policy issues Working Party on Manufactured Nanomaterials focus on testing ti and assessment methods
Nine projects currently active: database on EHS research research strategies on manufactured nanomaterials safety testing of a representative set of manufactured nanomaterials environmental applications OECD : WPMN manufactured nanomaterials and test guidelines co-operation on voluntary schemes and regulatory programmes exposure measurement and exposure mitigation alternative methods in nanotoxicology co-operation on risk assessment
OECD : WPMN Sponsorship Program NANOMATERIALS (13) fullerenes (C60) single-walled carbon nanotubes multi-walled carbon nanotubes silver nanoparticles gold nanoparticles iron nanoparticles carbon black titanium dioxide cerium oxide zinc oxide silicon dioxide dendrimers nanoclays END POINTS information / identification 9 parameters physical-chemical properties and material characterization 17 parameters environmental fate 15 parameters environmental toxicology 6 parameters mammalian toxicology 9 parameters material safety 3 parameters
ISO : Documentary Standards Technical Committee 229: Nanotechnologies supporting sustainable and responsible development of nanotechnologies improving quality, safety, security, consumer and environmental protection involves experts from about 40 countries formal working liaisons with another 18 ISO TCs and 7 international organizations including OECD, BIPM, EU, IRMM, VAMAS
ISO TC229 Working Group Structure JWG1 Terminology & Nomenclature (Canada) core term definitions JWG2 Metrology & Characterization (Japan) experimental techniques and protocols WG3 Health, Safety, Environment (USA) human and environmental toxicology protocols WG4 Material Specifications (China) heading down the path to product specs
nanoscale (Draft) Definitions from ISO one or more spatial dimensions in the range from 1 nm to 100 nm nanoscience the systematic study and understanding of matter, properties and phenomena related to the nanoscale nanotechnology the application of scientific knowledge to control and utilize matter at the nanoscale, where sizerelated properties and phenomena can emerge
TC229 Metrology Checklist Simple Questions: Clear material description Clear measurand Measurement unit Traceable measurements Defined method Validated method Available instrumentation Quality assurance tools Uncertainty budget
Pre-Normative Metrology Research Publication on SWCNT sample preparation protocols for 10 analytical techniques by NRC, NIST, NPL
TC229 WG3 Project 5 : Measurands NANOMATERIALS (8) Fullerenes Carbon nanotubes Titanium dioxide Calcium carbonate Zinc oxide Silicon dioxide Nickel Quantum dots CHARACTERISTICS (9) Agglomeration state Surface area Composition Surface chemistry Particle size distribution Shape Purity / Impurity Solubility Stability
Reference Materials Reference materials will be an important method to bring metrology and quality to the nanoscale ISO Guide 34 is the standard for producers homogeneity and stability are essential both physical and chemical properties important objective is reproducibility and process control Certified reference materials go even further validated uncertainty statements enable use as check standards or process calibration
Reference Material Defined Material, sufficiently homogeneous and stable with respect to one or more specified properties, which has been established to be fit for its use in a measurement process ISO Definition of Reference Material NIST offers over two thousand RM and SRMs includes nanoscale reference materials such as gold nanoparticles and single-walled carbon nanotubes
Reference Material Production Produce a homogeneous source of material Develop characterization tests and measurements Evaluate optimal packaging and storage conditions Prepare sufficient material for current / future needs Make material available to industry and toxicologists
NRC and FPInnovations: NCC RM Candidates Nanocrystalline cellulose (both dry and in solution) Homogenization and bottling Radiation sterilization with 10 kgy gamma rays Homogeneity testing Characterization testing with collaborators Data analysis, review and reporting
Nanocrystalline Cellulose Reference Materials NCC-1: 1 g bottles dry powder NCCS-1: 20 ml bottles 6% solution Measurands: crystal structure particle size distribution molecular weight elemental analysis carboxylic acid content zeta potential (solution only) surface characterization
Nanocrystalline Cellulose Reference Materials NCC-1: 1 g bottles dry powder NCCS-1: 20 ml bottles 6% solution Collaborators: FPInnovations NRC NIST NCI Virginia Tech Tokyo University McGill University INP-Pagora Grenoble INNVENTIA AB Stockholm North Carolina State University
Toxicology Studies on NCC Toxicity risk assessment is being conducted by FPInnovations under Canada s New Substances Notification Regulations (Health & Environment)
Conclusions One major obstacle to adequate characterization of engineered nanoparticles is the lack of scientifically credible nanoscale reference materials useful for validation and development of exposure assessment tools (instruments, protocols, methods) essential for standardization of toxicological evaluations (materials, protocols). A comprehensive approach to metrology and standardization will benefit NCC commercialization
Some things I didn t talk about International Metrology Workshops www.bipm.org Coordinated EU effort in nanoscale metrology www.co-nanomet.eueu Reference Material Database http://www.nano-refmat.bam.de Minimum characterization suite for toxicity http://characterizationmatters.org
SWCNT: Reference Material / OECD Sample NRC has early-stage reference material for high quality laser-produced single wall carbon nanotubes kg quantities of material known to be homogeneous oge eous for use in toxicity testing are required by OECD 300 120 mg bottles of material in powder form are being characterized by ICPMS, TGA, Raman, etc. in an international collaboration led by INMS
Gold Nanoparticles NIST offers 3 reference materials for gold nanoparticles: 10 nm, 30 nm and 60 nm diameter Mean GNP diameter is characterized using six techniques Summary ypresentation by Vince Hackley available at www.nist.gov 60 nm gold nanoparticles Atomic Force Microscopy Scanning Electron Microscopy Transmission Electron Microscopy Dynamic Light Scattering Electrospray-Differential Mobility Analysis Small Angle X-Ray Scattering
Gold Nanoparticle RM Data
Gold Nanoparticle RM Data The six different measurement techniques give nominal diameters that do not agree within their expanded uncertainties! This is VERY GOOD SCIENCE!! This is VERY GOOD SCIENCE!! These are VERY DIFFERENT MEASURANDS!!!