Abstract:The reactive oxygen species (ROS) like hydrogen peroxide (H2O2) generate commonly during the process of metabolism and the increased level of H2O2in tumor cells can be up to 0.5 nmol/104 cells/h comparing with normal cells, which provide a possibility for the usage of oxidation-responsive hydrogels in biological system. Herein, di-(1-hydroxylundecyl) diselenide was prepared by the nucleophilic substitution reaction between Na2Se2 and11-bromoundecanol and then used to react with IPDI to prepare an isocyanate-terminated diselenide crosslinker. Finally, a diselenide dextran hydrogel was fabricated by crosslinking dextran with the diselenide agent. The structure, swelling property, oxidation-responsive ability, rheology property and in vitro drug release behaviors of the diselenide dextran hydrogel were characterized and studied by 1HNMR, FT-IR, GPC, Raman spectrum, Rotational Rheometer and UV-vis respectively. The result showed that the hydrogel with lower crosslinking degree was higher in swelling ratio. Besides, the dissolution process was visually observed after H2O2 solution was added into the gel due to the decomposition of diselenide bonds in the polymer network, showing that the resultant hydrogel could be in response to the oxidation stimulus. Furthermore, in vitro drug release experiments were carried out by using rhodamine B (RhB) as a model drug and the results showed that the hydrogel could only release 45% of the loaded drug in 24 h without H2O2 and 90% of the loaded drug could be released in 14 h under an oxidizing environment (0.2wt% H2O2), indicating that the diselenide dextran hydrogel was a promising candidate for drug release.