A thermosensitive chitosan-based hydrogel barrier for post-operative adhesions' prevention

Post-operative peritoneal adhesions are common and serious complications for surgeons. They can cause pelvic pain, infertility, and potentially lethal bowel obstruction. We synthesized injectable hydrogels that formed by chemical modification through grafted hydrobutyl groups to chitosan chains. Gelation of hydroxybutyl chitosan (HBC) occurs in less than 60 s. Once formed, it can also be recovered completely. The residue time of hydrogels can extend to 4 weeks in Kunming mice. HBC hydrogels showed mild cytotoxicity to mice fibroblast cell (L929) and human vascular endothelial cell (ECV-304) in vitro and were biocompatible in the murine muscles, causing no adhesions for 4 weeks. HBC gels can form a durable barrier between defected cecum and abdominal wall. In a mice sidewall defect-bowel abrasion model, HBC gels showed significant efficacy in reducing adhesion formation.