Injectable hydrogels are very advantageous in skin tissue-engineering, but generally suffer from several issues including infection, insufficient hair follicle regeneration, and scarring. In this paper, an injectable antibacterial hydrogel is designed for wound healing via integrating antibacterial Ag₂₉ nanoclusters (NCs) and mangiferin (MF) molecules into the 3D network-structured chitosan (CH) hydrogel to eliminate bacterial infection and promote hair follicle/tissue regeneration. This design not only endows the hydrogel with excellent wide-spectrum antibacterial activities, superior biocompatibility, decent injectability, adequate swelling, and good degradability, but also favors the regeneration of capillary vessels/hair follicles/sweat glands for wound healings, which is the “holy grail” of skin tissue engineering. The antibacterial performance of the hydrogel is further improved through the controlled release of Ag species, the formation of a high local concentration of antibacterial Ag species on the hydrogel surface, as well as the capture of bacteria on the hydrogel surface via electrostatic interaction. In vivo experiments reveal that the hydrogel could eliminate bacterial infections and prompt the regeneration of hair follicles/capillaries of wounds, which significantly promotes the skin flap wound healing. This study could shed light on the design of multi-functional Ag NCs-based hydrogel for applications of skin tissue engineering and wound treatments.

可注射的水凝胶在皮肤组织工程中是非常有利的，但是通常会遇到一些问题，包括感染，毛囊再生不足和疤痕形成。本文设计了一种可注射的抗菌水凝胶，可通过整合抗菌Ag ₂₉来伤口愈合纳米簇（NCs）和芒果苷（MF）分子进入3D网络结构的壳聚糖（CH）水凝胶，以消除细菌感染并促进毛囊/组织再生。这种设计不仅使水凝胶具有出色的广谱抗菌活性，出色的生物相容性，良好的注射性，足够的溶胀性和良好的降解性，而且还有利于毛细血管/毛囊/汗腺的再生以用于伤口愈合，这就是“皮肤组织工程的“圣杯”。水银的抗菌性能可通过控制释放的Ag物种，在水凝胶表面上形成高浓度的局部抗菌银物种以及通过静电相互作用将细菌捕获在水凝胶表面上而得到进一步改善。体内实验表明，水凝胶可以消除细菌感染，并促进毛囊/伤口的毛细血管再生，从而显着促进皮肤皮瓣伤口的愈合。这项研究可能会为基于多功能Ag NCs的水凝胶的设计提供启示，以用于皮肤组织工程和伤口治疗。