A. Montgomery, S. Bawage, A. Chaudhary, S.R. Singh, K. Vig
Alabama State University,
Keywords: gold nanoparticles, miRNA, gene expression
Summary:Gold Nanoparticles are popular because of their use in drug delivery and other biomedical applications. However, not much is known about their toxicity. The purpose of the present study was to evaluate the toxicity of GNRs to HEp-2 cells. In the present study, 20nm GNRs were used. GNRs toxicity to the cells was tested using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Trypan Blue Cell Exclusion assay. MTT results showed 90% cell viability at 10 µg/mL compared to 56.4% at 50 µg/mL in 72 hours. The Trypan Blue Assay showed results in cell viability with 77.8% at concentrations of 10µg/mL and 55% at concentrations of 50µg/mL. We synthesized fluorescein isothiocyanate (FITC)-conjugated GNRs and investigated its localization in the cells. With the use of immunofluorescence microscopy, we observed that the GNRs entered the cells at 4 hours. We furthermore investigated the effect of GNRs on gene expression by miRNA expression analysis of cells. microRNA (miRNA) was extracted from the cells using miRNeasy kit (Qiagen). cDNA was synthesized and PCR array was done using miScript miRNA PCR Array (Qiagen). miRNA PCR array revealed upregulation of majority of genes in response to GNRs and showed a decrease in the average ΔCt values with GNRs treatment. The purpose of this study was to assess how the GNRs affected the cells at the molecular level to facilitate prospective applications. This work was supported by NSF-REU (DBI-1358923) to Dr. Komal Vig (PI) and by NSFCREST (HRD-1241701) to Dr. Shree S. Singh (PI).