Gelatin-Syringaldehyde-Zinc Hydrogel: A Triple-Action Bioactive Dressing for Infected Wound Regeneration

Skin injury disrupts the epidermal barrier, rendering tissues vulnerable to bacterial invasion and persistent oxidative stress, which collectively impair the healing process. To address these challenges, a multifunctional gelatin-syringaldehyde-zinc (GSZ) composite hydrogel herein was devised via the Michael addition of syringaldehyde (SA) to methacrylated gelatin (GelGMA), followed by Zn²⁺-mediated coordination cross-linking. The GSZ hydrogel exhibited a well-defined porous microstructure, rapid photocross-linking behavior, and favorable swelling capacity. In vitro studies confirmed its favorable biocompatibility, ability to promote cell proliferation and migration, and remarkable antioxidant and broad-spectrum antibacterial activities. In a mouse Staphylococcus aureus-infected full-thickness wound model, the GSZ hydrogel accelerated wound closure, facilitated epithelial regeneration, stimulated angiogenesis, and promoted collagen deposition. This study proposes a synergistic strategy for engineering bioactive hydrogels that integrate reactive oxygen species scavenging, antimicrobial function, and proregenerative cues into a single platform, thus offering a promising multifunctional dressing for the management of infected and chronic wounds.