PhD, University of Cincinnati, 2020, Arts and Sciences: Chemistry

Noble metal nanoparticles have been used as sensors utilizing the phenomenon localized surface plasmon resonance (LSPR). LSPR based sensors are competitive because of the high sensitivity and can be made label-free. LSPR sensors have great potential as diagnostic tools for point-of-care and in-field scenarios. In this work, I have developed three unique sensors that utilizes LSPR. First, a nanoparticle-based localized surface plasmon resonance (LSPR) assay to detect copper ions in biological samples in vitro was developed. After reducing the cellular Cu2+ ions to Cu+ ions using ascorbic acid, a `click' reaction is carried out to covalently couple a dye to the surface of a gold nanoparticle array. Then utilizing the ability to fabricate LSPR arrays on substrates we developed durable flexible nanoparticle substrates for point-of-care sensing. Second, I developed a rapid, LSPR based diagnostic test for chlamydia without the need for amplification. This technique can be developed into a strip and be used for other STIs in a multiplexed manner. Last, a flexible plastic, sensitive sensor for cortisol and neuropeptide y was developed. These sensors show low limits of detection, good reproducibility, and good selectivity in complex biological samples. Moreover, they all show excellent promise as point-of-care sensors which can greatly expand medical diagnostics for at-home and in the field use.

Committee: Laura Sagle Ph.D. (Committee Chair); Peng Zhang Ph.D. (Committee Chair); In-Kwon Kim Ph.D. (Committee Member); Pearl Tsang Ph.D. (Committee Member) Subjects: Analytical Chemistry