Figure 20.

Effect of embedded and non-embedded N-doped, Fe-doped, and Fe, N-doped TiO₂ nanoparticles (0.4 mg/mL) on (a) MCF-7 and (b) MDA-MB-231 GSSG-to-GSH ratio. Cells treated for 24 h with H₂0₂ (1 mM) were used as a positive control of the experiments, untreated used cells as a negative control, and cells treated with visible light without TiO₂ as an additional negative control. * p < 0.05 compared to negative control (untreated) cells. Data represent means ± standard deviation from five independent experiments.