Design and Development of ZnO/BMP-2 Sustained-Release Hydrogel for Enhanced Bone Tissue Repair

Bone infections caused by microbial invasion often lead to tissue damage and functional impairment. Although bone implants are a primary clinical approach to reduce recurrence and promote healing, the growing challenge of antimicrobial resistance necessitates innovative postoperative therapies to improve patient outcomes. In this study, a CG@ZnO/BMP-2 hydrogel with rapid antibacterial and bone regeneration capabilities was developed via a self-assembly technique. This approach leverages the chelation interaction between CG and ZnO, as well as the strong hydrogen bonding between CG and BMP-2. The resulting CG@ZnO/BMP-2 hydrogel exhibited a honeycomb-like structure with excellent swelling, water retention, and biodegradability. Antibacterial assays revealed that, under UV irradiation, the hydrogel achieved antibacterial rates of 85.4% against Escherichia coli and 87.3% against Staphylococcus aureus. The incorporation of ZnO conferred sustained antibacterial activity to the hydrogel. In vitro osteogenesis studies demonstrated that BMSCs gradually differentiated into osteoblasts over time, indicating robust osteogenic potential. Collectively, the CG@ZnO/BMP-2 hydrogel demonstrated a combination of effective antibacterial performance and accelerated bone-inducing functionality. This composite hydrogel holds significant promise for applications in bone infection treatment and bone tissue repair, especially for enhancing bone healing and minimizing postoperative infection recurrence.