Fig. 5
Enhanced inhibitory effect on tumor spheroids. a Dose-dependent inhibitory effect of Ru@SiO2 or Ru@SiO2-PA on tumor spheroids. SGC-7901 cells (6 × 105 cells/well) were seeded in ultra-low attachment 6-well plate and cultured for 2 days. Then, tumor spheroids were treated with Ru@SiO2 or Ru@SiO2-PA for 72 h, and imaged under a fluorescent microscope (magnification, 100 ×). b Quantitative analysis of tumor spheroids volume. c Real-time images of superoxide anion. SGC-7901 tumor spheroids cultured for 5 days were pre-incubated with DHE probe and treated 20 μg/ml Ru@SiO2 or Ru@SiO2-PA for 10–120 min. The Real-time generation of superoxide anion was imaged under a fluorescent microscope (magnification, ×100). d Quantitative analysis of superoxide anion. Bars with “*” or “**” represents P < 0.05 or P < 0.01 level, respectively