Internal gelation-based alginate hydrogel films incorporating Quercus infectoria gall extract for multifunctional wound dressing applications

Chronic wounds pose a major clinical challenge, as persistent infection, excessive inflammation, and oxidative stress significantly impede tissue repair. Developing multifunctional biomaterials capable of addressing these factors is essential for effective wound management. In this study, alginate- Quercus infectoria gall (QIG) hydrogel films were fabricated via internal gelation using calcium carbonate and glucono-δ-lactone to achieve uniform crosslinking. The optimized formulation exhibited adequate wound-fluid uptake (716.18 ± 25.05%), a balanced water vapor transmission rate (1,304.08 ± 80.67 g/m 2 /day), and high optical transparency (79.94 ± 3.48% transmittance), allowing visual monitoring of the wound bed without dressing removal. The hydrogel film demonstrated excellent encapsulation of QIG extract, achieving a high encapsulation efficiency (> 99%), and displayed a biphasic release profile, with approximately 62.57 ± 6.06% of the extract released within 24 h. Biological evaluations revealed that the films exhibited strong antioxidant activity and significant anti-inflammatory effects, evidenced by a 50.08 ± 3.19% reduction in nitric oxide production in LPS-stimulated macrophages. Moreover, the alginate–QIG hydrogel film demonstrated potent antibacterial efficacy, achieving up to 99.99% inhibition of bacterial growth after 24 h of treatment. Collectively, these findings indicate that alginate–QIG hydrogel films combine desirable physicochemical and biological characteristics, highlighting their potential as naturally derived multifunctional dressings for effective wound management.