In situ crosslinked injectable chondroitin sulfate hydrogel for preventing postoperative adhesion

Postoperative adhesion is a common clinical disease caused by surgical trauma, accompanying serious subsequent complications. Current non-surgical drug therapy and biomaterial barrier administration have limited therapeutic effects due to their inherent deficiencies. Therefore, developing a simple, effective, and feasible method to effectively prevent postoperative adhesions after surgical procedures remains a challenge. An injectable chondroitin sulfate complex hydrogel was prepared based on aldehyde-modified chondroitin sulfate (ChS-CHO) and hydrazine-modified chondroitin sulfate (ChS-ADH). The hydrogel showed enhanced strength and good self-healing ability. By using the Schiff base reaction principle that aldehyde group reacts with hydrazide to form hydrazone bond, C-A hydrogel physical barrier is formed at the wound site to reduce the occurrence of postoperative adhesion. There is no use of chemical crosslinkers in the whole reaction system to prepare C-A hydrogel, which has excellent biocompatibility and is safe and non-toxic. The results showed that C-A hydrogel showed excellent mechanical properties, good self-healing, and biocompatibility. The cecal-abdominal wall adhesion model and hepatic adhesion model of rats were constructed respectively to evaluate its preventive effect on postoperative adhesion. The results showed that C-A hydrogel had a more significant preventive effect on postoperative adhesion, and appears to be a promising candidate for postoperative adhesion.