Cytotoxicity of gold nanoclusters in human liver cancer cells

Abstract

Yanjie Yang,1,2 Jing Nan,3 Jianwen Hou,3 Bianfei Yu,1 Tong Zhao,1 Shuang Xu,1 Shuangyu Lv,2 Haixia Zhang1 1Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, Lanzhou University, Lanzhou, 2School of Medicine, Henan University, Kaifeng, 3School of Life Sciences, Lanzhou University, Lanzhou, People’s Republic of China Abstract: In this study, we synthesized water-soluble fluorescent gold nanoclusters (Au NCs) stabilized with dihydrolipoic acid (DHLA). The cytotoxicity of these Au NCs was then assessed in the normal human hepatic cell line (L02) and the human hepatoma cell line (HepG2) at different exposure times. Cell viability was normal in both cell lines at 24 hours and 48 hours; however, the growth of HepG2 cells was significantly inhibited at 72 hours. The change in lactate dehydrogenase level was strongly correlated with cell viability after 72 hours incubation with DHLA–capped Au NCs, and the increase in cellular reactive oxygen species may be related to the decrease in cell viability. Growth inhibition of HepG2 cells was possibly due to difficultly passing the checkpoint between G1 phase and S phase. The anticancer activity of DHLA–capped Au NCs should be considered when used in biomedical imaging and drug delivery. Keywords: gold nanocluster, cytotoxicity, cell viability, reactive oxygen species, cell cycle