Borate-Crosslinked Bioadhesives With Double Network Fabricated Using Dopamine-Conjugated Gelatin and Polyvinyl Alcohol Incorporating Catechin Acid: Potential in Biomedical Applications

The hydrogel bio-adhesive has demonstrated outstanding potential in regenerative wound care. Here, we prepared borate-crosslinked bioadhesive hydrogels (PPGB) composed of dopamine-conjugated gelatin (Gel-DA), polyvinyl alcohol (PVA), and catechin acid. Scanning electron microscopy revealed an interconnected porous microstructure within the PPGB matrix. Rheological characterization confirmed typical viscoelastic solid behavior, favorable injectability, and excellent self-healing capability, the latter of which was also supported by macroscopic observations. Antioxidant activity was validated through ABTS and DPPH radical scavenging assays. The PPGB adhesives exhibited strong adhesion to various material surfaces and moist organic tissues. Antibacterial testing demonstrated efficient activity against the typical Gram-positive and Gram-negative bacteria. Biocompatibility evaluation using CCK-8 assays and DAPI/phalloidin staining of NIH 3 T3 fibroblasts exposed to hydrogel extracts indicated good cytocompatibility. Furthermore, a scratch wound healing assay confirmed enhanced cell migration. Collectively, these findings present a straightforward strategy for engineering multifunctional hydrogel bio-adhesives with potential for biomedical applications. Highlights Dopamine-conjugated gelatin was synthesized. Borate-crosslinked PPGB hydrogels were fabricated as bioadhesives. PPGB hydrogels displayed good antioxidant activities. PPGB hydrogel bioadhesives exhibited strong adhesion to various materials and organs. PPGB hydrogels exhibit suitable cytocompatibility and cell-promoted migration.