Multifunctional Injectable Hydrogel Dressings for Effectively Accelerating Wound Healing: Enhancing Biomineralization Strategy

Bacterial infection can cause chronic nonhealing wounds, which may be a great threat to public health. It is highly desirable to develop an injectable wound dressing hydrogel with multifunctions including self-healing, remodeling, antibacterial, radical scavenging ability, and excellent photothermal properties to promote the regeneration of damaged tissues in clinical practice. In this work, dopamine-modified gelatin (Gel-DA) is employed for the first time as a biotemplate for enhancing the biomineralization ability of gelatin to synthesize dopamine-modified gelatin@Ag nanoparticles (Gel-DA@Ag NPs). Further, the prepared Gel-DA@Ag NPs with antioxidant activity and near-infrared (NIR) laser irradiation synergistic antibacterial behavior are fixed in the guar gum based hydrogels through the formation of borate/didiol bonds to possess remolding, injectable, and self-healing performance. In addition, the multifunctional hydrogels can completely cover the irregular wound shape to prevent secondary injury. More importantly, these hydrogel platforms under NIR can significantly accelerate wound healing with more skin appendages like hair follicles and blood vessels appearing. Therefore, it is expected that these hydrogels can serve as competitive multifunctional dressings in biomedical field, including bacteria-derived wound infection and other tissue repair related to reactive oxygen species overexpression.