Silver nanoparticle behavior, uptake and toxicity in Caenorhabditis elegans: Effects of natural organic matter and temperature

Tuesday, December 4, 2012

12:00 pm to 1:00 pm


Xinyu (Candy) Yang

Xinyu (Candy) Yang is a doctroal student at Nicholas School of the Environment.

Abstract: We exposed the nematode Caenorhabditis elegans to silver nanoparticle (Ag NP) suspensions with or without natural organic matter (NOM). We found that NOM (Suwannee River and Pony Lake fulvic acids) reduced Ag NP toxicity, and that Pony Lake fulvic acid (PLFA) rescued toxicity more effectively. Tissue total silver measurements indicated that PLFA reduced silver uptake upon ionic silver exposure, however, the tissue uptake upon citrate-coated Ag NP (CIT) exposure was not altered by PLFA . We found formation of NOM-Ag NP composites inside nematodes, and reduction of intracellular Ag NP uptake. Uptake was identified by the localization of electron-dense particles within lysosome-like structures in CIT exposure without PLFA, and was reduced in the context of PLFA co-exposure.