▎ 摘　　要

Graphene oxide (GO) is well known for its photo-reactivity with potential reduction under ultraviolet (UV) radiation. GO induces cytotoxicity in cancer cells even though the mechanism involved has not been firmly established when exposed to cancer cells. Therefore, to investigate the potential interaction of GO with UV and their impact on cancer cells, MCF-7 human breast cancer cells were exposed to GO, UV, or in combination, and the cellular impacts associated with these exposures have been identified. UV-irradiated GO showed differences in appearance, UV-absorbance, FTIR, and Raman spectra, indicating substantial changes in UV-irradiated GO structure compared to the non-irradiated GO. Furthermore, UV-irradiated GO reduced the cell viability of MCF-7 cells and increased the cellular level of ROS in the cancer cells that were dependent on the UV exposure time and GO concentration, respectively. Moreover, a synergistic increase in cellular ROS was observed when MCF-7 cells were treated with different GO concentrations followed by UV-irradiation. The synergistic interaction of GO and UV induced apoptotic cell death in MCF-7 cells as evidenced by the increases in MCF-7 cells exhibiting round cell morphology, nuclei condensation, activation of BAX and Caspase as well as the release of Cyt. C from mitochondria, suggesting the potential of UV-irradiated GO in cancer treatment.