Dynamic boronate ester crosslinked hydrogel with robust wet adhesion for regeneration-matched full-thickness corneal...

Full-thickness corneal perforation threatens vision, yet sutures and adhesives cause trauma and poor repair. Developing a hydrogel that combines wet adhesion, matched degradation, transparency, and biocompatibility remains challenging. We report a dynamic hydrogel built upon an alginate polysaccharide derivative (3-Aminophenylboronic Acid-Modified Sodium Alginate, SA-3APBA) as the component. This polysaccharide backbone forms reversible boronate ester crosslinks with polyvinyl alcohol (PVA) via its boronic acid groups, while its carboxyl/hydroxyl groups and chain entanglements provide hydrogen bonds. These features endow the material with mechanical compliance, controllable degradation, and strong wet tissue adhesion. The optimized 2 wt% SA-3APBA/4 wt% PVA hydrogel exhibits a storage modulus (G') of 0.04-0.6 kPa matching native cornea, a normalized mass change of 27.5%, and complete degradation within 12 days, aligning with the 10-14 day corneal regeneration window. It achieves wet adhesion of 17-26 kPa, which gradually decays during degradation to avoid damaging regenerated tissue. The hydrogel shows >90% transmittance and no cytotoxicity. In a rabbit full-thickness perforation model, it seals wounds within 24 hours, restores anterior chamber stability, and promotes orderly epithelial and stromal regeneration within 14 days without inflammation or neovascularization. This alginate polysaccharide-based strategy provides a promising path for corneal defect repair by synergizing adhesion, degradation, and regeneration.