Engineered nanoparticles (ENP) are increasingly used in manufacturing processes and as additives to consumer products to enhance product properties. Understanding the environmental fate and impact of ENPs relies on the ability to characterize them at relatively low levels in complex media, which often contains additional naturally occurring nanoparticles. We present the application of single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) and a recently developed hyphenated technique combining electrospray aerosol generation, particle size selection using differential mobility analysis (DMA), and elemental analysis using inductively coupled plasma mass spectrometry (ICP-MS) to characterize gold and silver nanoparticles in aqueous media. These methods are capable of detecting nanoparticles of 20-100 nm diameter at part-per-billion (ppb) levels in environmentally relevant aqueous solutions. These methods were used in an inter-comparison of NIST standard reference materials (SRMs). Following instrument characterization, the DMA-ICP-MS and sp-ICP-MS was used to assess the fate of gold nanoparticles in a solution containing daphnia magna. Insights into dose verifications obtained by DMA-ICP-MS and sp-ICP-MS will be discussed, as well as their performance for the analysis of the NIST SRMs.
See more of this Group/Topical: Transport and Energy Processes