▎ 摘　　要

Exposure to graphene is increasing with the extensive application and production of graphene and its derivatives. Graphene may be exposed to a variety of biomicroenvironments, in which the concentrations of bio-macromolecules vary. Thus, it is essential to study the toxic behaviors of graphene in different biomicroenvironments. In the present study, we investigated the toxic behaviors caused by graphene oxide (GO) in different biomicroenvironments and its potential mechanisms. Our results revealed that GO injured cells through reactive oxygen species (ROS) induction and induced apoptosis in protein-free microenvironment. However, GO-induced cytotoxicity was weakened remarkably in the presence of protein, which attributed to the reduction of GO internalization and ROS generation. GO induced cell cycle arrest in the G0/G1 phase when the protein concentration is low but had no remarkable cytotoxicity when the protein concentration was high. Our findings provide a basis for the prevention graphene toxicity.