Preparation and application of collagen scaffold-encapsulated silver nanoparticles and bone morphogenetic protein 2 for enhancing the repair of infected bone.

The healing of contaminated/infected bone defects is a significant clinical challenge. Here, a novel collagen scaffold composite encapsulating silver nanoparticles (AgNP) and bone morphogenetic protein 2 (BMP-2) was prepared to enhance the healing of infected bone defects. Collagen scaffolds conjugated with AgNP possessed strong antibacterial properties that were dependent on the release rate of Ag(+). After introducing BMP-2, the BMP-2/AgNP/collagen scaffold composites did not adversely affect the adherence or proliferation of bone marrow-derived mesenchymal stromal cells (BMSCs). Differentiation of BMSCs toward osteoblasts was induced by the upregulation of RUNX2, osteopontin and osteonectin expression. BMP-2/AgNP/collagen scaffold composites, therefore, possess the antibacterial activity of AgNP and the osteoinductivity of BMP-2, making these composites an ideal pharmaceutical for the regeneration of bone in infected wounds.