A novel multi-functional PVA- alginate hydrogel with dynamic bond crosslinking for infected wound repair

The development of multifunctional antibacterial hydrogel dressings with enhanced mechanical properties and biological activity is essential for advancing wound healing strategies. In this study, we report the design and synthesis of a novel multifunctional hydrogel (PVA-Alg/FP), developed by integrating Fe³⁺, protocatechualdehyde (PA), polyvinyl alcohol (PVA), and sodium alginate (Alg). The hydrogel was crosslinked via multiple dynamic bonds and hydrogen bonds, avoiding the use of toxic crosslinking agents and eliminating the need for additional modification or purification steps. This approach enables the straightforward and efficient preparation of the hydrogel. The resulting hydrogel exhibits outstanding mechanical properties, with a tensile strength of 88.2 kPa. More importantly, compared with conventional PVA-Alg hydrogels crosslinked by glutaraldehyde or epichlorohydrin, our PVA-Alg/FP hydrogel demonstrates a diverse range of functional characteristics, including a high self-healing efficiency of 87.4 % within 10 min, as well as plasticity, ductility, adhesion, Deferoxamine mesylate (DFO)-responsive removal, and near-infrared (NIR) photothermal properties. Additionally, it demonstrates outstanding biocompatibility and a broad spectrum of biological activities, including antioxidant, anti-inflammatory, and antibacterial effects, as well as promoting cell migration. Furthermore, the hydrogel accelerates full-thickness skin wound healing in a Staphylococcus aureus(S.aureus)-infected rat model, providing compelling evidence of its potential as a therapeutic material for infection-induced wounds.