Biomimetic Design of Underwater Adhesives Based on Tea Polyphenol-Modified Gelatin

Although many tissue adhesives with good biocompatibility are currently available, their lack of wet adhesion capacity significantly hinders their clinical application. Therefore, further development and exploration of new medical adhesives are necessary. Inspired by the adhesion mechanism of marine mussels, through modifying gelatin protein with gallic acid (GA) for wet adhesion and cross-linking gelatin (Gel) molecular chains with tea polyphenols (TP), the adhesive TP-GA/Gel was developed. The adhesive exhibited an adhesion strength of up to 130.47 kPa to porcine skin tissues and maintained a high adhesion state in various aqueous environments, demonstrating excellent and reproducible adhesion. Additionally, TP-GA/Gel possessed outstanding antimicrobial, antioxidant, and biocompatibility properties. In an in vivo wound healing study with SD rats, the wound area treated with TP-GA/Gel adhesive decreased from 10.3 mm² to 0.9 mm² after 15 days, promoting effective and scarless wound healing. These results highlight the promising clinical potential of TP-GA/Gel as a medical adhesive.