Antiadhesive, antibacterial, and anti-inflammatory sandwich-structured ZIF8-containing gauze for enhanced wound healing

Medical gauze is commonly used in clinical practice due to its low irritation, flexibility, and permeability. However, conventional gauze frequently lacks adequate antibacterial and anti-adhesion properties, and gauze that is only superhydrophobic or antibacterial seldom meets the full requirements of infected wound treatment. In this work, we report optimal air permeability, water and blood absorption, and biocompatibility, and effective antibacterial properties of a sandwich-structured gauze composed of a superhydrophobic outer layer, a zeolite imidazolate framework-8 (ZIF8) interlayer, and a superhydrophobic inner layer containing blood-drainage channels (denoted SZS gauze). Three ZIF8 interlayers, ZIF8-1, ZIF8-2, and ZIF8-3, were prepared by soaking medical gauze samples in a mixed solution of 50 mL methanol, 50 mL ethanol, and 0.25, 0.50, or 1.00 g zinc acetate before flat drying, and had Zn content of 0.28, 0.34, and 0.46 at.%, respectively, and their corresponding SZS gauze samples are denoted SZS-1, SZS-2, and SZS-3, respectively. Among all gauze samples, the SZS-2 showed the highest cytocompatibility toward L929 cells and effective in vitro antibacterial ability against E. coli and S. aureus. In a rat subcutaneous inflammation model, the SZS-2 showed complete biosafety and the best antibacterial and anti-inflammatory effects against E. coli and S. aureus mixed bacteria among all gauze samples including standard medical gauze and a sandwich-structured gauze with a blank interlayer between two superhydrophobic layers. These findings indicate that the SZS-2 gauze is a promising candidate for advanced wound care, particularly in the management of infected wounds.