Preparation of Carbon Nanotube Reinforced Gelatin-Chitosan-Hydroxyapatite Biocomposite for Bone Tissue Engineering

Uniform and highly stable dispersion of multi wall carbon nanotube (MWCNT) in aqueous solution using surfactant sodium dodecyl sulphate was prepared by physical adsorption of surfactant molecules on to the nanotubes which overcomes the van der Waals forces and prevents aggregation between individual nanotubes.Chemically functionalized MWCNT dispersion was also prepared by mixed acids using (3:1) (H2SO4: HNO3) that was obtained to be less cytotoxic than the physically functionalized MWCNT dispersion.Chemically functionalized MWCNT-Hydroxyapatite (HAp)-Chitosan-Gelatin composite scaffold samples were prepared by solution casting method after optimizing the cytotoxic effect results.The effect of varying content of MWCNTs on the physico-mechanical, thermal, morphological properties of the nanocomposites was evaluated.The chemical change of composite with varied MWCNT content was studied using FTIR and morphological characterization was done by SEM, where Porous structure was observed on the composites, which is supposed to be required as criteria of a bone scaffold to grow bone tissues.Compressive Strength (CS) of composite scaffold increased by 95.82% with increase of MWCNT content (from 0.1% to 0.25%).The thermal characterization of nano-composites was done by TGA and DSC and it was found that the nanocomposite containing 0.25% MWCNTs showed highest thermal stability.TGA of nanocomposites containing 0.25% MWCNT increased by 363.16% in comparison to that of nanocomposites containing 0.1% MWCNTs.However, due to highest cytotoxicity of nanocomposite having 0.25% CNTs, 0.1% composition was considered the best.