Development of an Injectable Antibacterial Adhesive Sealant for Sutureless Repair of Corneal Injuries

Corneal injuries and infections pose a serious threat to vision worldwide. Current corneal repair strategies face challenges associated with donor shortages, complex surgical procedures, and inadequate performance of existing sealants, including poor wet adhesion, excessive swelling, insufficient mechanical stability, and lack of intrinsic antibacterial activity. Herein, we developed an in situ injectable and intrinsically antibacterial hydrogel sealant (TAE) for sutureless corneal repair by integrating NHS-functionalized tetra-poly(ethylene glycol), amine-modified gelatin, and ε-polylysine. Upon delivery through a dual-barrel syringe, rapid covalent crosslinking between NHS esters and amine groups enabled fast gelation, conformal defect filling, and stable adhesion under wet physiological conditions. The optimized TAE hydrogel exhibited high optical transparency, restrained swelling behavior, strong wet-tissue adhesion, suitable mechanical properties, high burst pressure, and controlled degradation. In vitro studies demonstrated that the hydrogel supported corneal epithelial cell proliferation with favorable cytocompatibility while providing broad-spectrum antibacterial activity. In a rabbit lamellar stromal defect model, the TAE hydrogel promoted corneal regeneration by facilitating re-epithelialization, restoring transparency, and improving stromal organization while attenuating inflammatory responses and fibrosis-associated stromal remodeling compared with the untreated control group. These findings highlight TAE as a promising hydrogel sealant for sutureless corneal repair.