D. Jones, R. Merrifield, J. Lead, C. Stephan
Keywords: single cell ICP-MS, nanoparticles, biouptake, bioavailability
Summary:Single cell ICP-MS (SC-ICP-MS) is a new ICP-MS technique based on single particle (SP)-ICP-MS, which allows for the measurement of the metal content of individual single celled organisms. SC-ICP-MS allows for the quantification of both of the amount of metal within the cell and the number of cells containing the metal, permitting for the measurement of intrinsic metal as well as the uptake of ionic and NP metallic contaminants. Freshwater algae were exposed to gold and silver nanoparticles over a period of four days. The amount of NPs in suspension (exposure) and the amount of metal taken up by the cells (dose) were measured by SC-ICP-MS and the toxicity (biological response) was measured at various time points. We show that the percentage of the cell population containing metal NPs increases with both time and initial exposure concentration. The uptake of multiple NPs into individual cells was observed for higher concentration exposures along with evidence for intercellular interactions with the NPs.