Oxidative Stress Mediates the Effects of Raman‐Active Gold Nanoparticles in Human Cells

• DOI: 10.1002/smll.201001466
• Publication Date: 2010-11-22T09:43:04Z
• Authors: Avnesh S. Thakor; Ramasamy Paulmurugan; Paul Kempen; Cristina Zavaleta; Robert Sinclair; Tarik F. Massoud; Sanjiv S. Gambhir
• Keywords: Dichlorofluorescein; Viability assay; HeLa

Abstract Polyethylene glycol (PEG)ylated Raman‐active gold nanoparticles (PEG‐R‐AuNPs) consist of an interchangeable Raman organic molecule layer held onto a nanocore by silica shell. PEG‐R‐AuNPs have been shown preclinically to increase the sensitivity and specificity spectroscopy, with picomolar multiplexing capabilities. Although clinical trials are being designed use functionalized in various applications (e.g., target dysplastic bowel lesions during colonoscopy), effects these on human cells remain unknown. The occurrence mechanisms underlying any potential cytotoxicity induced (0–1000 PEG‐R‐AuNPs/cell) investigated immortalized HeLa HepG2 cell lines at several time points (0–48 h) after exposure. Using fluorometric assays, viability (MTT), reactive oxygen species (ROS) generation (dichlorofluorescein diacetate), protein oxidation (protein carbonyl content), total cellular antioxidant concentrations (metmyoblobin‐induced ABTS) assessed. Analysis lipid using enzyme immunoassay (8‐isoprostane concentrations), gene expression enzymes quantitative reverse transcription polymerase chain reactions, intracellular location transmission electron microscopy is also undertaken. cause no either or acute setting as ROS balanced upregulation. Following prolonged exposures (48 relatively high (1000 PEG‐R‐AuNPs/cell), found within vesicles inside cells. Under conditions, minimal amount seen both owing increases oxidative stress, most likely due overwhelming defenses. Evidence stress‐induced damage includes increased oxidation. further vivo toxicity studies necessary, initial encouraging results show that setting, which bodes well for future living subjects.