Professor Kathryn Riley of Swarthmore College

"Direct electrochemical speciation and quantitation of Ag(I) and AgNPs released from textiles"

The unique properties of engineered nanomaterials (ENMs) have enabled their increased use for a range of environmental, medicinal, and commercial applications. However, ENMs can undergo many dynamic processes in environmental and biological matrices (e.g., dissolution, aggregation, adsorption of small molecules, etc.), which alter their physicochemical properties. To fully characterize ENM properties in relevant matrices, in situ analytical tools are needed, which our group has addressed through the development of several electroanalytical methods. First, we optimized a highly reproducible linear sweep stripping voltammetry (LSSV) method to quantify silver nanoparticle (AgNP) dissolution kinetics in real-time. Separately, we have developed a technique that utilizes a single nanoparticle electrochemistry technique, particle-impact voltammetry (PIV), to monitor AgNP aggregation. More recently, we coupled our LSSV and PIV techniques to speciate dissolved Ag(I)(aq) and in-tact AgNPs released from AgNP-containing textiles in real-time. Specifically, since AgNPs are frequently included in sports-performance clothing, we evaluated silver release from cotton fabrics exposed to simulated sweat solutions to mimic a release and human exposure scenario. This talk will explore the development and application of each electroanalytical technique, as well as opportunities for future development.