MWCNTs and SWCNTs based Nanocomposites for Cartilage and Bone Tissue Regeneration

摘要

Cartilage and bone defects, which are caused by a variety of reasons such as traumatic injuries, osteoarthritis, osteoporosis or bone cancers, represent common and severe clinical problems. Developments in nanotechnology and tissue engineering have provided promising ways to repair and replace damaged cartilage and bone [1-3]. Since human cartilage and bone extracellular matrices are nanostructured, novel biomimetic nanomaterials are desirable for cartilage and bone regenerations [4, 5]. Thus, the objective of this research is to create novel biologically inspired tissue engineered cartilage and bone scaffolds via two types of carbon nanotubes and nanocrystalline hydroxyapatite (nHA) for improving bone and cartilage regeneration. Our results showed that nanocomposites containing magnetically synthesized B-SWCNTs had superior cytocompatibility properties when compared to non-magnetically synthesized SWCNTs and blank controls. B-SWCNTs have much-smaller diameters and are twice as long as their non-magnetically prepared counterparts, indicating that the dimensions of carbon nanotubes can have a substantial effect on osteoblast functions. For the cartilage regeneration, through electrospinning we designed a series of novel 3D biomimetic nanostructured scaffolds based on H_2 treated MWCNTs, poly L-lysine and biocompatible poly(L-lactic acid) (PLLA) polymers. Our in vitro human bone marrow mesenchymal stem cell (MSC) differentiation results demonstrated that incorporation of the biomimetic MWCNTs and poly L-lysine coating can induce more chondrogenic differentiations of MSCs than controls.