R.I. MacCuspie, N. Patel, K. Marchionda
Natural Immunogenics Corp,
Keywords: silver nanoparticles, measurements
Summary:Silver nanoparticles (AgNPs) exist in a cycle of transformations under environmentally and biologically relevant conditions. As these conditions vary, the equilibrium of these cycles between AgNP and ionic forms are shifted, presenting measurement challenges. These challenges can lead to nanoecotoxicity measurement artifacts, however these artifacts canoften be avoided with proper planning . A significant portion of this talk will focus on recent advances have led to consensus methods and numerous datasets. For example, NIST Special Publication NIST SP-1200-13 describes UV-vis measurements of particle concentrations enables measurements of AgNP dissolution kinetics without processing or separation as validated by chemical analysis. Additionally standardized sample preparation methods for specific applications such as textiles now exist [NIST SP-1200-8]. Example data on consumer products including commercially available dietary supplements will also be included, especially for colloidal silver products. References: 1. Akaighe, N., et al., Humic Acid-Induced Silver Nanoparticle Formation Under Environmentally Relevant Conditions. Environmental Science & Technology, 2011. 45(9): p. 3895-3901. 2. MacCuspie, R.I., et al., Challenges for physical characterization of silver nanoparticles under pristine and environmentally relevant conditions. J Environ Monit, 2011. 13(5): p. 1212-26. 3. Petersen, E.J., et al., Identification and Avoidance of Potential Artifacts and Misinterpretations in Nanomaterial Ecotoxicity Measurements. Environmental Science & Technology, 2014. 48(8): p. 4226-4246. 4. Zook, J.M., et al., Measuring agglomerate size distribution and dependence of localized surface plasmon resonance absorbance on gold nanoparticle agglomerate size using analytical ultracentrifugation. ACS Nano, 2011. 5(10): p. 8070-9.