In situ preparation of multicomponent polymer composite nanofibrous scaffolds with enhanced osteogenic and angiogenic activities

Bioactive ceramics are extensively used for bone repair and regeneration, which release ions to initiate apatite formation and promote osteogenic differentiation eventually resulting in strong bonding to bone. Toward enhancing the bioactivity of polymeric nanofibrous scaffolds, this work presents a one-step in situ sol-gel method to fabricate electrospun composite nanofibrous scaffolds encapsulating well dispersed ceramic nanoparticles overcoming the limitations of current preparation techniques. Transmission electron micrographs revealed uniform distribution of ceramic nanoparticles within the polymer nanofibers. The multicomponent scaffolds were found to release calcium, silicon and phosphate ions that mimic the dissolution and bioactivity of conventional bioactive glasses. The scaffolds enhanced the bioactivity of PCL fibers as observed through enhanced apatite formation in simulated body fluid. The released ions markedly enhanced the proliferation and osteogenic differentiation of human mesenchymal stem cells and the angiogenic activity of human endothelial cells in vitro. This work has important implications for engineering the next-generation nanostructured scaffolds that exhibit multi-biofunctional activities for bone tissue regeneration.