Carbon Nanotubes for Bone Tissue Engineering

Abstract

Biological tissues are compositionally and structurally exquisite – a complex network of proteins and cells organised with molecular-precision. Unfortunately, in the absence of an organ transplant or tissue graft, there are no technologies that can completely repair or restore this complex system when it fails. With the hopes of regenerating failing tissue, tissue engineers have developed scaffold structures able to support cell life. As yet, these structures are unable to recreate the complexities of the biological environment, limiting the success of this approach. Nanotechnologies have realised methods to make materials with defined nanoscale properties. Continued research may lead to sophisticated nanobiomaterials, with properties that rival the complexities of biological environments and improve tissue regeneration. To this end, we explored the use of carbon nanotubes (CNTs) within the field of tissue engineering. We investigated the use of 3D CNT scaffolds in bone tissue engineering using strong and porous ceramic scaffold structures coated with CNTs. We abate limitations in previous fabrication methods limiting coating of CNTs throughout porous structures. We demonstrate these surfaces are high quality aligned CNTs, are non toxic and able to support attachment, spreading and proliferation of adipose derived stem cells (ASCs) and human osteoblasts. Following the development of a 3D CNT material, we investigated the potential for using CNTs to create well-defined nanoenvironments capable of regulating cell differentiation. This research is the first report of non-biased quantitative measurement of cell shape during long term differentiation. In contrast to previous techniques, it allows direct measurement of shape rather than that of the underlying substrate. This approach offers novel insights into the relationship between the nanoenvironment, cell shape and cell differentiation. The novel nanomaterials presented in this thesis, demonstrate the potential of nanotechnologies for artificially engineered tissues and organs. Continued research of nanomaterials promises to better recreate the complexities of the biological environment, instructing healthy regenerative processes and promoting tissue function.