Biomass-derived washable composites for accelerating the healing of infected wounds

Advanced sustainable biomedical materials are urgently needed for clinical applications; however, developing biomedical materials with exceptional mechanical and bactericidal properties as well as removable functionalities to reduce unintended secondary injury remains a challenge. Here, we report a biomass-derived composite consisting of water-soluble fish gelatin (FG) and antibacterial ZnO@silk fibroin (ZSF) microspheres for potential application as the wound dressing. The ZSF microspheres are embedded in a FG matrix to realize the stretchable, antibacterial, and removable ZSF/FG composites. By introducing glycerin as the plasticizer, ZSF/FG composites deliver a tensile strength of 4.5 MPa and stretchability of 550%. Acting as both the germicide and hydrophile components, ZSF microspheres endow the composites with excellent antibacterial capacity and water solubility. To prevent secondary injury, the ZSF/FG composites can be easily removed from the wounds by simply exposing them to excess water. Additionally, the ZSF/FG composites exhibit favorable biocompatibility and sustain high cell viability of over 100%. The full-thickness skin wound model on infected mice demonstrated an efficient rate of wound closure and a reduced inflammatory response. The ZSF/FG composite shows promise to hasten the healing of infected wounds and is expected a promising candidate as wound dressing for clinical therapy.