AAAR 34th Annual Conference
October 12 - October 16, 2015
Hyatt Regency
Minneapolis, Minnesota, USA
Abstract View
Evaluating the Evolution of Silver Nanoparticles in Gastrointestinal Tract through Application of State-of-the-Art Methods to Simulated Gastric Fluids of Increasing Complexity
ANDREW AULT, Jessica Axson, Diana Stark, Amy Bondy, Sonja Capracotta, Justin Keeney, Andrew Maynard, Martin Philbert, Ingrid Bergin, University of Michigan
Abstract Number: 198 Working Group: Nanoparticles and Materials Synthesis
Abstract Uncertainty remains regarding the evolution and fate of ingested silver nanoparticles (AgNPs) after exposure from an array of commercial products. Thus, it is important to understand the fundamental chemical and physical processes leading to decreases (dissolution) or increases (aggregation) in AgNP size under high salt and acidic conditions of the gastrointestinal (GI) tract, as well as in the presence of proteins such as pepsin and pancreatin. In this study, particle growth was observed on the timescale of seconds-to-minutes for simulated gastric fluid (SGF) replicating the salt content and pH of the human stomach. High time resolution data from Nanoparticle Tracking Analysis (NTA) (30 second) combined with transmission electron microscopy (TEM) were used to explore the kinetics as a function of pH, size, and coating. In addition, a USP 2 apparatus was constructed and modified to study the long-term dissolution of nanoparticles in the presence of different proteins and fasted/fed conditions of the GI tract. This apparatus was then expanded to study the evolution of AgNPs using a multi-compartment system representing the stomach, duodenum, and jejunum. The resulting solutions were aerosolized with electrospray ionization to generate protein-coated AgNP aerosol for size and chemical analysis with an SMPS and single particle mass spectrometry. Taken together, the results of this multi-faceted study of AgNP evolution are providing key insights into the modification of AgNPs during passage through the GI tract.