A tannin-functionalized soy protein-based adhesive hydrogel as a wound dressing

Bioinspired strategies for preparing multifunctional hydrogels have drawn attention. Among these hydrogels, the adhesive types have been extensively studied, However, most of them exhibit poor mechanical properties, short-term adhesion, and no antibacterial activity. Inspired by the mussel adhesion mechanism, an adhesive hydrogel made from tannic acid (TA), acrylamide (AM), and soy protein isolate (SPI) is presented in this study. The adhesive hydrogel showed a large tensile strain (932%), high tensile strength (45.8 kPa), high toughness (155.15 kJ·m−3), and ideal compressive properties owing to the formation of a hybrid double network (DN). This hydrogel exhibited satisfactory adhesion to various materials, including muscle tissue, metal, rubber, glass, plastic, and wood. The TA-PAM-SPI hydrogel also showed good antibacterial properties against Escherichia coli and Staphylococcus aureus, in addition to self-healing properties and biocompatibility. With these characteristics, the TA-PAM-SPI hydrogel was used as a wound dressing to accelerate wound healing and skin tissue regeneration. This study provides a convenient approach to preparing multifunctional hydrogels and promoting the application of SPI in biomedical materials.