Figure 4. CdSe/ZnS QDs induced oxidative damage in NRK cells. (A) Measurements of several oxidative damage indicators, including malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px), in NRK cells treated with CdSe/ZnS QDs and/or N-acetylcysteine (NAC, antioxidant) using the commercial kits. (B) Reactive oxygen species (ROS) content in NRK cells treated with CdSe/ZnS QDs and/or NAC using the commercial kit. *P < 0.05 vs. control group; #P < 0.05 vs. CdSe/ZnS group.