Poster abstracts
Poster number 37 submitted by Brian Scarpitti
Single particle imaging to monitor subcellular delivery of gold nanoparticles
Brian T. Scarpitti (OSBP), Sanjun Fan (Department of Chemistry and Biochemistry, The Ohio State University), Zachary D. Schultz (Department of Chemistry and Biochemistry, The Ohio State University)
Abstract:
Gold nanoparticles (NPs) have utility in biology as both therapeutics and sensors due to their biological stability, low cytotoxicity, and biocompatibility. For example, gold NPs are currently under clinical trial for use as anticancer agents via photothermal therapy and drug delivery (e.g., AuroLase® Therapy by Nanospectra, CYT-6091 (Aurimune™) by CytImmune Sciences). Gold NPs are also uniquely suitable for multimodal and intraoperative imaging of tumors, and as cellular sensors of pH or specific biomarkers. To better apply gold NPs in the clinic, we seek to understand the uptake and subcellular distribution of these NPs.
Sensing and therapeutic applications of NPs would be improved and expanded by ensuring NPs reach subcellular targets efficiently. However, rapid and quantitative methods for subcellular localization of physiologically relevant numbers of NPs remains challenging. Fluorescence is affected by the optical properties of the gold NPs, leading to high variability of signal from single fluorescently labeled particles. Fortunately, these same optical properties enable bright Raman scattering signals. Our recent work shows that Raman spectroscopy can provide reproducible, sharp, and photostable spectral features for NP quantification. Our direct method of quantification enables diffraction-limited imaging of gold NPs and reliable colocalization with fluorescent organelle labels. Future work includes colocalization experiments using a novel super-resolution Raman imaging approach to characterize the subcellular distribution of gold NPs. The goal of these future experiments will be to assess and optimize endosomal escape through surface functionalization of the NPs.
Keywords: Raman imaging, gold nanoparticles, cellular delivery