Controlled Aggregation, Stabilization, and Phase Transfer of Gold Nanoparticles

Presenter: Jared Iversen

Presenter Status: Undergraduate student

Academic Year: 22-23

Semester: Spring

Faculty Mentor: Bogdan Negru

Department: Chemistry

Funding Source/Sponsor: McNair

President's Strategic Plan Goal: Sustainability and Environmental Inquiry

Screenshot URL: https://drive.google.com/uc?id=1H0ZPEFonX2e1JC9m0jwIL26bRQ3jRklP

Abstract:
Throughout the last 50 years, gold nanoparticle solutions have been used to explore a plethora of chemical and physical phenomena. The size control of nanoparticles is accomplished through synthesis and subsequent aggregation. Aggregation describes the process of bringing gold monomers together in solution to form dimers, trimers, and oligomers with commonly available chemical agents. To stabilize the resulting analyte and halt the aggregation process, a polymer can be used to coat the surface of the suspended nanoparticles. Our research group uses polyvinylpyrrolidone (PVP), a water soluble polymer, to stabilize the aggregate at an appropriate time. The current literature suggests that functionalization of the gold surface after stabilization with PVP is possible. We are in the process of finding the minimum amount of PVP needed to coat nanoparticles of the size and shape commonly used by our lab. To monitor the process of aggregation and polymer stabilization, we use UV-Vis spectroscopy. The ultimate goal of this research is to functionalize the surface of the nanoparticles and examine the impacts of these changes to chemical detection using Surface-Enhanced Raman Spectroscopy (SERS).