Zn2+-Loaded adhesive bacterial cellulose hydrogel with angiogenic and antibacterial abilities for accelerating wound healing

Wound healing is a process that requires angiogenesis and antibacterial activities and it remains a challenge for both experimental and clinical research worldwide. Zn2+ has been reported to be widely involved in angiogenesis and exerts antibacterial effects, making it suitable as a treatment to promote wound healing. Therefore Zn2+-loaded adhesive bacterial cellulose hydrogel was designed to observe its angiogenic and antibacterial abilities in the wound healing process.The characterization, tensile strength, swelling behaviors and antibacterial activity of bacterial cellulose/polydopamine/zeolitic imidazolate framework-8 (BC/PDA/ZIF8) hydrogels were tested. Cell-Counting-Kit-8 (CCK8), transwell, tube formation and real time qunantitative PCR (qRT-PCR) assays were performed to evaluate the cell compatibility of BC/PDA/ZIF8 hydrogels in vitro. A full-thickness defect wound model and histological assays were used to evaluate the BC/PDA/ZIF8 hydrogels in vivo.The prepared BC/PDA/ZIF8 hydrogels exhibited suitable mechanical strength, excellent swelling properties, good tissue adhesion, efficient angiogenic and antibacterial effects and good performance as a physical barrier. In vivo experiments showed that the BC/PDA/ZIF8 hydrogels accelerated wound healing in a full-thickness defect wound model by stimulating angiogenesis.This study proved that BC/PDA/ZIF8 hydrogels possess great potential for promoting satisfactory wound healing in full-thickness wound defects through antibacterial effects and improved cell proliferation, tissue formation, remodeling and re-epithelialization.