Tissue-adhesive, antibacterial and antioxidant hydrogel sealant for sealing colorectal anastomotic leakage and preventing postoperative adhesion

Surgical treatment of colorectal diseases typically involves excising the diseased portion of the bowel and anastomosing the remaining sections to re-establish continuity. Surgical suturing has limitations in preventing anastomotic leakage and postoperative adhesion. To address these challenges, a tissue-adhesive, antibacterial, and antioxidant hydrogel was designed to cover and seal colorectal anastomotic wounds. The hydrogel was formed in situ by simply mixing oxidized hyaluronic acid (OHA), adipic acid dihydrazide-modified hyaluronic acid (HA-ADH), ε-poly-L-lysine (ε-PLL), and tannic acid (TA). The hydrogel exhibited a rapid gelation rate and self-healing ability. Compared with commercial fibrin glue, the hydrogel had superior tissue adhesive strength and wound sealing performance. The hydrogel displayed potent reactive oxygen species scavenging ability and antibacterial activity against both gram-positive and gram-negative bacteria. The hydrogel also exhibited good biodegradation and biocompatibility. In a cecum-abdominal wall adhesion model in rats, the hydrogel attached firmly to the injured tissues and served as a physical barrier to prevent adhesion formation. In anastomotic leakage models after colon resection in rats and rabbits, the hydrogel effectively sealed the anastomotic leakage, prevented postoperative adhesion, and promoted anastomotic healing. Thus, this multifunctional hydrogel has strong clinical potential for preventing anastomotic leakage and adhesion formation after colorectal surgery.