Retinal pigment epithelial cells, imaged in a confocal microscope, incorporate functionalized Au NP. The nuclei are stained blue with Hoechst and the mitochondria in the cytoplasm are stained with Mitotracker Red. The reflection channel (gray spots, arrows) indicate aggregated NP in the cytoplasm

A Nanoparticle-Based Sensorof Oxidative Stress

DMR-0934218

Optical absorption of functionalized gold NP at 520 nm (disaggregated) and 620 nm (aggregated), as measured by photoacoustic spectroscopy. Introduction of FeCl3 (an oxidizer) causes the NP to aggregate, increasing the signal at 620 nm.

Oxidative stress is a critical process in biological systems, involved in both normal and pathological functions; thus it is a commonly measured endpoint. Current methods for measuring oxidative stress are affected by artifacts, such as auto-oxidation. We are developing a new measurement approach based on the aggregation of functionalized gold NP in the presence of reactive oxygen species.

Students: Yuan-Hao Lee (UTHSCSA), Zannatul Yasmin (UTSA); Advisors: Randolph D. Glickman (UTHSCSA), Kelly Nash (UTSA)