Design of functional vancomycin-embedded bio-derived extracellular matrix hydrogels for repairing infectious bone defects

The treatment of infectious bone defects has become a troublesome issue in orthopedics. The disease requires effective anti-infective and bone-reconstruction therapeutic functionalities. In this study, we prepared a novel antibacterial material (vancomycin-impregnated periosteal extracellular matrix [Van-PEM]) by embedding vancomycin in a periosteal extracellular matrix (PEM)-derived hydrogel via physical stirring for the treatment of infectious bone defects. The microstructure, porosity, degradation, and release properties of this antibacterial hydrogel were characterized. The in vitro hemolytic reaction, cytotoxicity, osteogenic ability, and antibacterial properties were also carefully studied. The results showed that the Van-PEM hydrogel possessed a fibrous network structure with high porosity. Moreover, the hydrogel demonstrated slow degradation in vitro and could release vancomycin for at least 1 week. The hydrogel showed no cytotoxicity and possessed good biocompatibility with blood cells. It also promoted osteogenesis and exerted a significant bactericidal effect. Subsequently, the anti-infection and bone-healing abilities of the antibacterial hydrogel were investigated in a rat model of infectious calvarial defects, and the infectious skull defect was successfully cured in vivo. Therefore, Van-PEM hydrogels may represent a promising therapeutic approach for treating infectious bone defects.