Research Paper Volume 13, Issue 19 pp 23119—23132

Figure 1. ZnO NPs induce cytotoxicity and ROS production in A549 cells. (A) Transmission electron microscopy image of ZnO NPs and the analysis of size distribution. (B) A549 cells were incubated with ZnO NPs at different concentrations for 24 h and cell viability was determined using CCK-8 assay. Data were presented as the mean ± SEM. ^**P < 0.01 (n = 3, t-test). (C) Cell apoptosis was monitored by annexin V-FITC staining and flow cytometry analysis. Annexin-V positive cells were presented as the mean ± SEM. ^**P < 0.01 (n = 3, t-test). (D) A549 cells were incubated with ZnO NPs at different concentrations for 6 h. Intracellular ROS generation was detected by DCFH-DA fluorescent probe and flow cytometry. All the data were presented as the mean ± SEM. ^**P < 0.01 (n = 3, t-test).