Fabrication of autofluorescent porous silica nanoparticles for redox-responsive drug release

Porous silica nanoparticles were prepared by emulsion-condensation route. The silica nanoparticles with diameter of 50 nm have both accessible center-radial large pore channels (19.9 nm) and small pore size of 3.5 nm. The hierarchical porous structure endows them large pore volume for loading drugs and sustained release property. The silica nanoparticles were further modified with glucose-oxidized glutathione. The formulated Schiff base and disulfide bonds render the silica nanoparticles auto-fluorescent and redox-responsive properties. The cleavage of disulfide bonds caused by reactive thiols facilitates aminomethylbenzoic acid (AMA) release. The release of drug leads to the loss of fluorescence, which would be used to monitor the drug delivery and carrier distribution.