Preparation and properties of a novel thermo-sensitive hydrogel based on chitosan/hydroxypropyl...

Chitosan-based thermosensitive hydrogels are known as injectable in situ gelling thermosensitive polymer solutions which are suitable for biomaterials. In this study, a novel thermosensitive hydrogel gelling under physiological conditions was prepared using chitosan together with hydroxypropyl methylcellulose and glycerol. Hydroxypropyl methylcellulose is to facilitate the thermogelation through large amounts of hydrophobic interactions. Glycerol in heavy concentration destroys the polymer water sheaths promoting the formation of the hydrophobic regions, and lowering the phase transition temperature. The thermosensitive hydrogels showed a physiological pH ranging from 6.8 to 6.9 and gelation time within 15min at 37°C. The prepared hydrogels were characterized by FT-IR, XRD, SEM, and rheological studies, mechanical studies and contact angle studies. The properties of degradability, cytotoxicity and protein release behaviors of the hydrogels were investigated. The results indicate this thermosensitive hydrogel possess good fluidity, thermosensitivity and biodegradability, as well as low-cytotoxicity and controlled release, showing the potential use in biomedical applications.