Zhengzheng Fu,1,* Jingwen Zou,1,* Jing Zhong,1 Jipang Zhan,1 Lian Zhang,1 Xiaoru Xie,1 Lai Zhang,1,2 Wenqiang Li,3 Renliang He1 

1Department of Dermatologic Surgery and Dermatologic Oncology, Dermatology Hospital of Southern Medical University, Guangzhou, Guangdong Province, 510000, People’s Republic of China; 2Guangdong Pharmaceutical University, Guangzhou, Guangdong Province, 510006, People’s Republic of China; 3Engineering Technology Research Center for Sports Assistive Devices of Guangdong, Guangzhou Sport University, Guangzhou, Guangdong Province, 510500, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Wenqiang Li; Renliang He, Department of Dermatologic Surgery and Dermatologic Oncology, Dermatology Hospital of Southern Medical University, Guangdong Provincial Dermatology Hospital, 2 Lujing Road, Yuexiu District, Guangzhou, Guangdong Province, 510000, People’s Republic of China, Email liwq@gzsport.edu.cn; zshrl2006@smu.edu.cn

Background: The skin regulates body processes. When damaged, it is prone to breeding bacteria, causing inflammation and impeding wound healing. There is an urgent need for new dressings that can combat bacteria to aid in infectious wound repair.
Methods: In this study, a curcumin-loaded nanocomposite hydrogel dressing (GelMA/AHA-Gel@Cur) with antibacterial properties and strong toughness was synthesized, designed to combine the modified gelatin-based hydrogel (GelMA/AHA) with curcumin-coated gelatin (Gel@Cur) nanoparticles to promote the healing of bacterial infection wounds. Under UV irradiation, methylacrylylated gelatin (GelMA) and aldehyaluronic acid (AHA) formed a composite network hydrogel through radical polymerization and Schiff base reaction. Meanwhile, the residual aldehyde group on the molecular chain of AHA securely locked Gel@Cur nanoparticles in the hydrogel network through Schiff base reaction.
Results: The addition of Gel@Cur nanoparticles not only enhanced the hydrogel’s mechanical strength but also facilitated a sustained, gradual release of curcumin, endowing the composite hydrogel with robust antimicrobial capabilities. In an animal model of infected wounds, the composite hydrogel significantly improved wound closure, healing, and vascularization compared to the control group. Hemocompatibility tests confirmed the hydrogel’s safety, with a hemolysis ratio of just 0.45%. Histological evaluation following treatment with the composite hydrogel showed improved tissue architecture, increased collagen deposition, and regeneration of dermal gland structures.
Conclusion: The GelMA/AHA-Gel@Cur composite hydrogel exhibits excellent mechanical properties, potent antimicrobial activity, and controlled drug release, along with superior cell and hemocompatibility. These characteristics make it a promising material for infected wound repair and a potential candidate for clinical skin regeneration applications.

Keywords: Nanocomposite hydrogel dressings, infected wound repair, antibacterial properties, drug delivery