Using single particle ICP-MS as a tool for understanding metallonanoparticles transformation during nanotoxicity assays

M.E. Johnson, S.K. Hanna, E.J. Petersen, B.C. Nelson, L.L. Yu
National Institute of Standards and Technology, US

Keywords: single-particle-ICP-MS, C. elegans, gold nanoparticles, quantification

Summary:

The work presented will establish a method for employing SP-ICP-MS toward the characterization of ENPs following their exposure to a model organism, C. elegans. Sample preparation, SP-ICP-MS analysis, data processing, particulate transport efficiency evaluation, and critical calculations will be discussed. This work combines a SP-ICP-MS technique and tissue digestion toward the characterization of ENPs in biological exposures. A SP-ICP-MS method was first developed for sizing Au ENPs using a well-characterized nanomaterial, NIST RM 8012 and 8013, and then implemented for the characterization of nanoComposix Au ENPs of the following sizes: 30, 60, 80, and 100 nm. Alkaline digestion of biological tissue has been successfully used to liberate ENPs from tissue, therefore C. elegans digestion was optimized by testing increasing concentrations of tetramethylammonium hydroxide (TMAH). Nanoparticulate body burdens were measured for each Au ENP uptake condition. Finally, size distributions and particle number concentrations were determined for all ENPs dispersed in water, ENPs dispersed in exposure media, and C. elegans along with body burdens for each Au ENP uptake condition.