Understanding Toxicity Effects of Nanostructures
Wednesday, October 12, 2016
Danielle Gorka is a graduate student in the Department of Chemistry
Astract: Nanomaterials are increasingly being used in consumer products due to their unique optical, electronic, and antibacterial properties. However, proliferated use of nanomaterials will lead to increased entrance into the environment where toxicity can occur to plants and other organisms. The focus of my research is to understand the origin of this organismal toxicity and methods for its reduction through engineering. Nano silver was chosen as the subject of study due to its prevalent use in consumer products. Specifically, the effect of three silver nanomaterials (silver nanoparticles, silver nanocubes, and silver nanowires) was examined in environmentally relevant and model organisms including Lolium multiflorum, Danio rerio, Caenorhabditis elegans, and several bacterial strains. Shape was shown to affect the toxicity of silver nanomaterials to L. multiflorum; this effect was not found in other species. To further understand the shape-specific toxicity, dissolution was studied. While it is often assumed to be the cause of silver nanomaterial toxicity, we concluded that dissolution alone did not account for all of the toxicity shown. Instead, physical contact between the nanomaterial and plant was found to be necessary for shape-based phytotoxicity. This work will help determine methods of engineer nanostructures to reduce environmental toxicity while retaining functional properties.