Carbon Nanofiber/Polycaprolactone/Mineralized Hydroxyapatite Nanofibrous Scaffolds for Potential Orthopedic Applications

Hydroxyapatite (Ca-10 (PO4)(6)(OH)(2), HAP), a multi-mineral substituted calcium phosphate is one of the most substantial bone mineral component that has been widely used as bone replacement materials because of its bioactive and biocompatible properties. However, the use of HAP as bone implants is restricted due to its brittle nature and poor mechanical properties. To overcome this defect and to generate suitable bone implant material, HAP is combined with biodegradable polymer (polycaprolactone, PCL). To enhance the mechanical property of the composite, carbon nanofibers (CNF) is incorporated to the composite, which has long been considered for hard and soft tissue implant due to its exceptional mechanical and structural properties. It is well-known that nanofibrous scaffold are the most-prominent material for the bone reconstruction. We have developed a new remarkable CNF/PCL/mineralized hydroxyapatite (M-HAP) nanofibrous scaffolds on titanium (Ti). The as-developed coatings were characterized by various techniques. The results indicate the formation and homogeneous distribution of components in the nanofibrous scaffolds. Incorporation of CNF into the PCL/M-HAP composite significantly improves the adhesion strength and elastic modulus of the scaffolds. Furthermore, the responses of human osteosarcoma (HOS MG63) cells cultured onto the scaffolds demonstrate that the viability of cells were considerably high for CNF-incorporated PCL/M-HAP than for PCL/M-HAP. In vivo analysis show the presence of soft fibrous tissue growth without any significant inflammatory signs, which suggests that incorporated CNF did not counteract the favorable biological roles of HAP. For load-bearing applications, research in various bone models is needed to substantiate the clinical availability. Thus, from the obtained results, we suggest that CNF/PCL/M-HAP nanofibrous scaffolds can be considered as potential candidates for orthopedic applications.