Figure 10.

Chitosan-gated fluorescent mesoporous silica nanoparticles (FMSNs). (i) Schematic illustration of the design of chitosan-gated MSNs for monitoring drug release in vitro. The as-synthesised nanoparticles are composed of naphthalimide-dye-functionalised chitosan (Cs-Nac) as the gatekeeper, an MSN nanoparticulate scaffold and Rhodamine 6G (R6) as the model cargo agent. On glutathione (GSH) addition two fluorescent emissions corresponding to the release of R6 and cleaved Cs-Nac are observed. (ii) A TEM image of as-synthesised MSNs. (iii) Fluorescence images of MRC–5 cells with different GSH concentration. (A) The as-synthesised MSNs with low GSH concentration. (B) MSNs in MRC-5 without any other treatment. (C) MSNs with high GSH concentration. Adapted with permission from reference [126]. Copyright (2020) American Chemical Society.