Fig. 5. TiO₂ NPs inhibited the growth of HepG2 cells. L02 and HepG2 cells were added to 6-well plates and co-cultured with different concentrations of TiO₂ NPs for 48 h for cell counting. (A) After co-culturing with TiO₂ NPs for 48 h, the number of L02 cells underwent no clear change. (B) When HepG2 cells were co-cultured with TiO₂ NPs for 48 h, the number of cells decreased. All data are presented as mean ± standard error of the mean. *p < 0.05, **p < 0.01.