Carbon nanotubes-reinforced polylactic acid/hydroxyapatite porous scaffolds for bone tissue engineering

In the field of bone defect repair, critical requirements for favorable cytocompatibility and optimal mechanical properties have propelled research efforts towards the development of composite materials. In this study, carbon nanotubes/polylactic acid/hydroxyapatite (CNTs/PLA/HA) scaffolds with different contents (0.5, 1, 1.5 and 2 wt.%) of CNTs were prepared by the thermally induced phase separation (TIPS) method. The results revealed that the composite scaffolds had uniform pores with high porosities over 68% and high through performances. The addition of CNTs significantly enhanced the mechanical properties of resulted PLA/HA, in which the 1.5 wt.% CNTs/PLA/HA composite scaffold demonstrated the optimum mechanical behaviors with the bending elastic modulus of (868.5 +/- 12.34) MPa, the tensile elastic modulus of (209.51 +/- 12.73) MPa, and the tensile strength of (3.26 +/- 0.61) MPa. Furthermore, L929 cells on the 1.5 wt.% CNTs/PLA/HA scaffold displayed good spreading performance and favorable cytocompatibility. Therefore, it is expected that the 1.5 wt.% CNTs/PLA/HA scaffold has potential applications in bone tissue engineering.