Mussel-inspired adhesive zwitterionic composite hydrogel with antioxidant and antibacterial properties for wound healing

The skin can be easily injured and attacked by external pathogens, leading to wound infection and wound healing delay. Traditional dressings adhere to wounds only and can cause secondary damage to the new epithelium and bleeding. Herein, a highly adhesive zwitterionic composite hydrogel wound dressing (PDA/PSBMA/NFC/Zn2+ [PSNZn]) with outstanding antibacterial properties, good biocompatibility and excellent rheological properties was prepared by introducing zinc ion-loaded polydopamine (PDA)-coated nanofibrillated cellulose into a covalently-crosslinked sulfobetaine methacrylate (SBMA) network. In vitro and in vivo experiments showed the broad-spectrum and lasting antibacterial activity of the PSNZn composite hydrogel against Escherichia coli and Staphylococcus aureus. In summary, the PSNZn composite hydrogel is an excellent wound dressing candidate with efficient antibacterial properties, high adhesion, excellent biocompatibility and good rheological properties.