Fig. 3.

(a) TEM images, (b) hydrodynamic size analysis and (c) absorption spectra of MnO₂ and MnO₂@PD1-CM; (d) zeta potential and (e) Coomassie brilliant blue staining of PD1-CM, MnO₂ and MnO₂@PD1-CM; (f) immunoprecipitation and western blot analysis to examine the orientation of PD-1 on PD1-CM and MnO₂@PD1-CM; (g) oxygen generation from the reaction of MnO₂ with H₂O₂ in 10 ​mM PBS buffer (pH ​= ​6.5); (h) absorption spectra of MnO₂ and the solution after reacted with 10 ​mM GSH, the insert was the concentration of Mn²⁺ in corresponding solution; (i) absorption spectra of methylene blue (MB) after reacted with H₂O₂ or GSH-treated MnO₂.