A multifunctional γ-polyglutamic acid/guar gum hydrogel film with antibacterial, analgesic and wound healing properties for infected wounds

Infected wounds are often plagued by dual challenges of persistent bacterial colonization and severe pain, which synergistically impede tissue repair. This study designed a novel multifunctional hydrogel film (G3/γ-PGA/GG-A/B) by integrating γ-polyglutamic acid (γ-PGA), third-generation dendrimers (G3), and guar gum (GG), with loading of amoxicillin (AMX) and bupivacaine (BUP). The solubilization effect of G3 and the hydrogel's unique network structure enhance the release rate of hydrophobic BUP, overcoming the poor delivery efficiency of lipophilic anesthetics in traditional hydrogels and enhancing long-term analgesic efficacy. In vitro assays confirmed that the film achieves over 99% bactericidal rates against Escherichia coli and Staphylococcus aureus , with no obvious cytotoxicity, and no significant damage to major organs in vivo . In C57BL/6 mouse models, G3/γ-PGA/GG-A/B treatment achieved a wound healing rate of 99.12 ± 0.44% for infected wounds within 18 days, with intact epidermal regeneration and orderly collagen deposition. In spared nerve injury (SNI) and plantar incision models (PIM), the film significantly prolonged thermal paw withdrawal latency and increased 50% mechanical withdrawal threshold, delivering potent analgesia for up to 5 days. This all-in-one hydrogel dressing integrates anti-infection, long-acting analgesia, and wound repair functions, offering a promising solution to clinical management of complex infected wounds.