In vivo rat subcutaneous tissue response of binder-free multi-walled carbon nanotube blocks cross-linked by de-fluorination

Binder-free multi-walled carbon nanotube (MWCNT) blocks from fluorinated MWCNTs were prepared using thermal heating and a compression method in vacuo. The resulting carbon nanotube blocks are lighter than graphite, can be machined and polished, possess average bending strengths of 102.2 MPa, a bending modulus of 15.4 GPa, and moderate wettability. The binder-free MWCNT blocks possess good biocompatibility when tested in the subcutaneous tissue of rats in vivo, which were covered by thin granulation tissue, 40-70 mu m in thickness, comprising a few lymphocytes, cell with large cytoplasmic spaces like fibroblasts and foreign-body giant cells. That is indicative of a slight inflammatory response than MWCNT/resin blocks and poly(methyl methacrylate). This material can potentially be employed as an alternative artificial hard tissue or internal bone plate that makes use of the properties of CNTs. (C) 2008 Elsevier Ltd. All rights reserved.