Fig. 6

ZnO NPs induced alterations in cells viability and were taken up by BV2 and PC12 cells. BV2 (a) and PC12 (b) cells were treated with ZnO NPs at doses of 0, 5, 10, 15, 20, 30, 40 or 50 μg/mL for 1, 3, 6, 12, 24 or 48 h. Cell viability was determined using the MTT assay. The LDH level in cell culture medium of BV2 (c) and PC12 (d) cells. (e)TEM images of BV2 and PC12 cells exposed to ZnO NPs (30 μg/mL) for 1 h. ZnO NPs were taken up by PC12 cells and located in the vesicles. What’s more, a sunken with ZnO NPs in the cytomembrane was observed in BV2 cells. However, numerous vacuoles but not granular NPs were observed in the cytoplasm of BV2 cells. The red arrows show the internalization and localization of ZnO NPs. The yellow arrows show the empty vesicles. Results shown as means ± SD from three independent experiments, compare with control group, *P < 0.05, **P < 0.01. Abbreviations: ZnO: zinc oxide nanoparticles; MTT: 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; LDH: lactic dehydrogenase; TEM: transmission electron microscopy; SD: Standard deviation