Composite Hydrogel Dressings with Enhanced Mechanical Properties and Anti-Inflammatory Ability for Effectively Promoting Wound Repair

Yuqin Feng,1,2 Si Qin,3 Huarun Li,3 Yemei Yang,1 Yushi Zheng,1 Hongsheng Liu,4 Wei Yin Yap,1,5 Xianyi Zhou,1 Ju Wen2,3 1Department of Dermatology, the Third Affiliated Hospital of Southern Medical University, Guangzhou, 510630, People’s Republic of China; 2The Second School of Clinical Medicine, Southern Medical University, Guangzhou, 510280, People’s Republic of China; 3Department of Dermatology, Guangdong Second Provincial General Hospital, Guangzhou, 510317, People’s Republic of China; 4Guangdong Huace Life Medicine Research Center, Guangzhou, 511450, People’s Republic of China; 5School of International Education of Southern Medical University, Guangzhou, 510515, People’s Republic of ChinaCorrespondence: Xianyi Zhou; Ju Wen, Email zxy1962@163.com; wenju3139@163.comBackground: Hydrogel dressings have been used as a crucial method to keep the wound wet and hasten the healing process. Due to safety concerns regarding the gel components, low mechanical adhesiveness, and unsatisfactory anti-inflammatory capacity qualities for practical uses in vivo, leading to the clinical translation of wound dressings is still difficult.Methods: A type of composite hydrogel (acrylamide/polyethylene glycol diacrylate/tannic acid, ie, AM/PEGDA/TA) by double bond crosslinking, Schiff base, and hydrogen bond interaction is proposed. The mechanical characteristics, adhesiveness, and biocompatibility of the hydrogel system were all thoroughly examined. Additionally, a full-thickness cutaneous wound model was employed to assess the in vivo wound healing capacity of resulting hydrogel dressings.Results: Benefiting the mechanism of multiple crosslinking, the designed composite hydrogels showed significant mechanical strength, outstanding adhesive capability, and good cytocompatibility. Moreover, the hydrogel system also had excellent shape adaptability, and they can be perfectly integrated into the irregularly shaped wounds through a fast in situ forming approach. Additional in vivo tests supported the findings that the full-thickness wound treated with the composite hydrogels showed quicker epithelial tissue regeneration, fewer inflammatory cells, more collagen deposition, and greater levels of platelet endothelial cell adhesion molecule (CD31) expression.Conclusion: These above results might offer a practical and affordable product or method of skin wound therapy in a medical context.Keywords: hydrogel dressing, tannins, multiple-crosslinking, anti-inflammatory, full-thickness wound healing