Tuning polycaprolactone–carbon nanotube composites for bone tissue engineering scaffolds

This report describes the mechanical, thermal and biological characterisation of a solid free form microfabricated carbon nanotube–polycaprolactone composite, in which both the quantity of nanotubes in the matrix as well as the scaffold design were varied in order to tune the mechanical properties of the material. The creep and stress relaxation behaviour of the composite material was analysed to identify an optimal composition for bone tissue engineering. Moreover, the morphology and viability of osteoblast-like cells (MG63) on composite scaffolds were analysed using scanning electron microscopy and MTT assays. Our data demonstrate that by changing the ratio of CNT to PCL, the elastic modulus of the nanocomposite can be varied between 10 and 75 MPa. In this range, the geometry of the scaffold can be used to finely tune its stiffness. However our PCL–CNT nanocomposites were able to sustain osteoblast proliferation and modulate cell morphology. Thus we show the potential of custom designed CNT nanocomposites for bone tissue engineering.