Construction of double network hydrogels using agarose and gallic acid with antibacterial and anti-inflammatory properties for wound healing

Gallic acid (GA) has attracted extensive attention due to its excellent health benefits. Our recent work demonstrated that GA could be self-assembled into hydrogels. However, the poor mechanical properties and rapid degradation of GA hydrogels presented challenges for further applications. In this study, agarose (AG), a water-soluble polysaccharide, was used with GA to develop a double network hydrogel (GA-AG). Physical and chemical tests demonstrated that the GA-AG hydrogel at ratio of 4:5 had the highest cross-linked structure, along with excellent porosity, good water retention and a swelling ratio of 9.72 %. In addition, the cross-linked network structure enabled the GA-AG hydrogel to have good mechanical properties and better viscosity than the pure GA hydrogel. The glass transition temperature of the GA-AG hydrogel increased from 59.49 °C to 65.54 °C, while its disintegration rate decreased from 99.07 % to 64.37 % within 48 h. In vitro tests showed that the GA-AG hydrogel had excellent antibacterial activity and biocompatibility. Meanwhile, we demonstrated that this double network hydrogel significantly reduced inflammation and accelerated wound healing in vivo . From the results of our study, we expect that this stable GA-AG double network hydrogel has potential applications in wound healing.