A redox and pH dual-triggered drug delivery platform based on chitosan grafted tubular mesoporous silica

Abstract Tubular mesoporous silica (T-mSiO2) was facilely synthesized through a co-template method by using cetyltrimethylammonium bromide and α-Fe2O3 as the dual templates, and then disulfide (–SS–) bonds and carboxyl groups (–COOH) were introduced to the resultant T-mSiO2 via the reaction with 2-carboxyethyl 2-pyridyl disulphide. The obtained –SS– grafted T-mSiO2 (SS-T-mSiO2) was then grafted with chitosan (CS) via the amidation reaction between the –COOH groups on SS-T-mSiO2 and the –NH2 groups on CS. The CS grafted SS-T-mSiO2 (CS-SS-T-mSiO2) was fully characterized by various technologies such as transmission electron microscopy, energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. Finally, the as-synthesized CS-SS-T-mSiO2 was used as the carrier for redox and pH dual-triggered delivery of 5-fluorouracil (5-FU), an anti-cancer drug, and the results indicate that the developed CS-SS-T-mSiO2 might be a potential responsive carrier for redox and pH dual-triggered drug delivery.