Injectable and self-healing hydrogel containing nitric oxide donor for enhanced antibacterial activity

The wound bacterial infections have become an intractable problem to human health. Multifunctional wound dressing materials with excellent adhesion, antibacterial as well as wound healing properties are still desperately needed to resist wound infection. In this work, an injectable hydrogel has been prepared, which chitosan and hyaluronic acid were cross-linked by aldehyde modified polyethylene glycol (PEG). For improving the antibacterial property, S-nitrosothiols was used as nitric oxide (NO) donor to provide a sustained NO release. The gelation time, microstructure, pH responsiveness, injectability, self-healing property as well as NO release profile were characterized. Quick and efficient antibacterial potency towards E. coli and S. epidermidis was confirmed in vitro with contact-killing assays. The co-culturing experiment with NIH 3 T3, HFF-1 and bEnd.3 cells indicated excellent biocompatibility of the hydrogels. Most importantly, the hydrogels showed the ability to accelerate the cell migration, demonstrating a potential to promote wound healing by scratch-wound assay. The current work provided a new type of injectable self-healing hydrogel for antibacterial function and infectious skin repair, leading to great potentials for infected wound healing.