Preparation and Cytotoxicity of High-aspect-ratio Gold Nanorods at Single Cell Level
We have synthesized high-aspect-ratio gold nanorods(GNR) by using a three-step seed-mediated growth method.The aspect ratio of the GNRs is approximately 14.The modification of the GNRs was achieved by replacing the CTAB molecules on the surface of gold nanorods with the 11-mercaptoundecanoic(MUDA) molecules.The cytotoxicity of the as-prepared GNRs and their effects on endocytosis,adhesion,proliferation,intracellular reactive oxygen species(ROS) level and cytoskeleton of the cells were studied.Interestingly,by using the 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyl-tetrazolium bromide(MTT) assay,the GNRs did not show a significant toxicity to HeLa cells.However,single cell viability assays showed that GNR uptake could influence the cell adhesion at the early stage,though the effect was not much,and the cell proliferation was promoted to some degree.Moreover,large amounts of GNR uptake will lead to increased intracellular ROS level and impaired the cell skeleton.