Tri-network PVA/chitosan/gelatin hydrogel modified by tannic acid with self-healing, adhesive and anti-inflammatory properties to accelerate wound healing

Wound inflammation is a key issue in wound healing as it often causes serious complications and delays wound healing. In this study, hemostatic and antimicrobial hydrogels composed of polyvinyl alcohol (PVA), chitosan (CS) and gelatin (Gel) were prepared. Phenylboronic acid (3-CPBA) and tannic acid (TA) were introduced to modify the multinetwork hydrogel to promote wound repair. PGCPT-1.2 hydrogel had a water content of >85 % and was biocompatible. Due to the antibacterial effect of chitosan itself. The PGCPT hydrogel exhibited 100 % antimicrobial activity against both Escherichia coli and Staphylococcus aureus within 12 h. The hydrogel exhibited shape memory behavior and self-healing ability. Histological analysis showed that PGCPT-1.2 hydrogel reduced tumor necrosis factor-α (TNF-α) levels by accelerating collagen deposition. The wound healing rate at day 14 was 97 % ± 0.4 %. PGCPT-1.2 hydrogel dressing with 1.2 % TA addition had the best effect in promoting wound healing, and it is a promising dressing for promoting wound healing and a therapeutic strategy worth developing.