Nano-hydroxyapatite/polyamide 6 scaffold as potential tissue engineered bone substitutes

In this study, nano-hydroxyapatite/polyamide 6 composite scaffold was prepared by phase separation and particle leaching combined method (PS/PL), and the scaffold, cultured with and without mesenchymal stem cells (MSCs), was investigated in vitro and in vivo. The scanning electron microscope photographs show a three-dimensional interconnected macroporosity of the scaffold. The compressive strength of the scaffold is 3.27 +/- 0.60 MPa while the porosity is 81.72 +/- 0.68%. The biological results show that the scaffolds act as a template for the adhesion, growth, differentiation and proliferation of cells and have no negative effects on the MSCs in vitro. In the animal experiments, n-HA/PA6 scaffolds and MSCs cocultured scaffolds were implanted into the critical sized calvarial defect of rats respectively, to study their biocompatibility and osteogenesis in vivo. Both pure scaffolds and MSCs hybridised scaffolds exhibited favourable biocompatibility and osteogenesis. In contrast with pure scaffolds, the hybrid scaffolds can accelerate the bone reconstruction. These results indicate that n-HA/PA6 composite porous materials are suitable materials for bone tissue engineering and have the feasibility to be widely used in orthopaedics for clinical application.