An injectable and rapidly degraded carboxymethyl chitosan/polyethylene glycol hydrogel for postoperative antiadhesion

Postoperative peritoneal adhesion will result in serious complications for patients and increase their hospitali-zation costs. The critical period for postoperative adhesion formation is 3-5 days after surgery. Constructing a simple, safe and rapidly degradable material for postoperative antiadhesion is still a great challenge. Herein, an injectable and biocompatible hydrogel was fabricated via Schiff base reaction between carboxymethyl chitosan (CMC) and dialdehyde-functionalized polyethylene glycol (DF-PEG), which exhibited wet tissue adhesion, self-healing property and attractive rapid degradation performance within one week. The CMC/DF-PEG hydrogel can cover irregular wounds and fix on the targeted tissue in situ, generating physical barrier for antiadhesion. In the cecum-sidewall abrasion model, the CMC/DF-PEG hydrogel powerfully reduced the severity of peritoneal adhesion. Notably, the mechanism of antiadhesion was associated with its ability to balance the extracellular matrix (ECM), fibrinolytic system and inhibit inflammatory responses during the healing of peritoneal injuries. Thus, the matched degradation performance and barrier effect make the CMC/DF-PEG hydrogel a promising solution for postoperative antiadhesion in surgery.