A fast and dual crosslinking hydrogel based on vinyl ether sodium alginate

Abstract Optimal modification and gelation strategies of polysaccharide hydrogels have been developed for biomedical applications. Herein, a kind of fast crosslinking alginate hydrogel with superior gel properties was prepared for the first time combining dual crosslinking mechanisms. Firstly, sodium alginate (SA) was modified by vinyl ether side chains through one-step amidation reaction with aminopropyl vinyl ether (APVE) catalyzed by EDC/NHS. Just within 10 s, the grafting product of SA-VE was demonstrated to form hydrogen bonded hydrogel SA-VE/H2O spontaneously. Based on this mechanism, a dual crosslinking alginate hydrogel SA-VE/DTT was fabricated through introducing thiol-ene click chemistry reaction with dithiothreitol (DTT) under UV exposure. According to rheological results, the photo-crosslinking process was completed within 5–9 min. Combining hydrogen bonding and thiol-ene click chemistry, the dual crosslinking mechanism was proved to bring the hydrogel system not only fast gelation but also superior storage modulus up to 13373 Pa and excellent stability of over 1 month. All the hydrogels exhibited non-cytotoxicity towards NIH-3T3 fibroblasts. Furthermore, the 26 s rapid hemostasis behavior of SA-VE exhibited in rat tail hemostasis experiment reveals its potential application in wound dressing materials.