Fig. 3From: Chitosan-capped enzyme-responsive hollow mesoporous silica nanoplatforms for colon-specific drug deliverya The corresponding ξ potentials of HMSS, HMSS–NH2, HMSS–N=N–COOH, and HMSS–N=N–CS; b The TGA curves of HMSS–NH2, HMSS–N=N–COOH, and HMSS–N=N–CS (the inset: the photograph of (a) HMSS–N=N–COOH and (b) HMSS–NH2); c Size distribution of HMSS, HMSS–NH2, and HMSS–N=N–CS inset: the corresponding PDI values of nanoparticles; and d FT-IR spectra of HMSS–NH2, HMSS–N=N–COOH, HMSS–N=N–CS, and CSBack to article page