Hydrogel Bioadhesives with Extreme Acid‐Tolerance for Gastric Perforation Repairing

Abstract Hydrogel bioadhesives have emerged as one of the most promising alternatives to sutures and staples for wound sealing and repairing, owing to their unique advantages in biocompatibility, mechanical compliance, and minimally invasive manipulation. However, only a few hydrogel bioadhesives have been successfully used for gastric perforation repair, due to their undesirable swelling when in direct contact with extremely acidic gastric fluids, and are thereby accompanied by a gradually deteriorating adhesion performance. Herein, an acid‐tolerant hydrogel (ATGel) bioadhesive is developed, which integrates two distinct components, an acid‐tolerant hydrogel substrate and an adhesive polymer brush layer. The ATGel bioadhesive can form instant, atraumatic, fluid‐tight, and sutureless sealing of gastric perforation, and enable robust biointerfaces in direct contact with gastric fluids, addressing the key limitations with sutures and commercially‐available tissue adhesives. Moreover, in vivo investigation on gastric perforation of rat model validates the proposed acid‐tolerant bioadhesion, and identifies the mechanisms for accelerated gastric perforation repair through alleviated inflammation, which suppresses fibrosis and enhances angiogenesis.