▎ 摘　　要

Context: The use of graphene oxide (GO) in biomedicine and cancer therapy has increased significantly owing to its unique physical and chemical properties. As a consequence, the toxicity of GO in the environment and in humans has garnered more and more attention. Objective: In this paper, we studied the potential cytotoxicity of GO nanosheets via examining the effect of GO on the viability, cellular colony formation and proliferation of a human breast cancer MDA-MB-231 cell line, which was an ideal model used to study breast disease in vitro. Methods and results: The results suggested that higher concentrations of GO (>= 100 mu g/mL) exhibited time-and dose-dependent cytotoxicity against MDA-MB-231 cells, suppressed the colony-forming capacity and cellular proliferation. Moreover, higher concentrations of GO increased the proportion of G0/G1 phase cells and induced the LDH release, as well as the generation of intracellular ROS which was also remarkably increased and may directly related with cytotoxicity. Conclusion: Together, the above results suggested that GO can induce cytotoxicity against human breast cancer MDA-MB-231 cells probably due to the cellular ROS generation, which providing useful toxicity and mechanism information that can help to better inform safety assessments of GO.