Fig. 4
Multiple enzyme-like activities and cytoprotection against ROS of PBNPs. (A) CAT-like activity of PBNPs determined by TPA-Na. (B) POD-like activity of PBNPs utilizing guaiacol as the chromogenic substrate. (C) SOD-like activity of PBNPs determined by an SOD assay kit. (D) H2O2 depletion of PBNPs determined by titanium sulfate method. (E) OH· depletion capacity of PBNPs determined by EPR. (F) O2·− depletion of PBNPs determined by EPR. (G) ROS in HaCaT cells was detected by flow cytometry combined with DCFH/DCF ROS detecting system. (n = 3; mean ± s.d.; ns, not statistically significant; *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001)