Effect of Functionalized Carbon Nanotubes on the Synthesis of Hydroxyapatite Nanoparticles

Abstract

The purpose of this study was to investigate the effect of the functionalized carbon nanotubes (CNT) on the nucleation of the HA nanoparticles. In this work, solutions of calcium nitrate tetra hydrate and diamonium hydrogen phosphate in water were used as Ca, P precursors. The former solution was added to an aqueous suspension of MWNTs-COOH. Different CNT functionalization percentage ratios of 1%, 2%, 3%, 4% and 5% were examined. X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) experiments confirmed that the resulting powders were composed of hydroxyapatite. The Scanning Electron Microscopy (SEM) images illustrated a short distance effect of CNTs on the formation of the HA nanoparticles. In addition, a more detailed observation performed by Transmission Electron Microscopy (TEM) depicted the flake-like morphology of the nanoparticles. Based on the results of this research, the crystallinity decreased due to the CNT addition to the synthesis media. The sample containing a CNT functionality percentage of 5% revealed a preferred crystalline orientation compared with the samples composed of less CNT functionality percentage of 1%, 2%, 3% and 4%.

Surface porosity and roughness of micrographite film for nucleation of hydroxyapatite

“…39 The CAO stretching vibrations due to CO 22 3 were also presented at 870, 1417 and 1456 cm 21 . The presence of CO 22 3 ion indicated that our HAp from SiO 2 /Si substrate and from uncompressed MGF were contaminated with the carbonate ion. The contanimation is commonly found in both synthetic and natural HAp 49 that OH and PO 32 4 ions in HAp are replaced by CO 22 3 ion.…”

“…11,12 For the external materials that are bioactive, such as chitosan, 13 collagen, 14 and polymer, 15 the nucleation can be facilitated by the surface chemistry of the materials such as functional groups, 16 charge, 17 and ion exchange. 18 However, for materials with poor bioactivity, such as zirconia, 19 titanium, 20 alumina, 21 carbon nanotubes, 22 and graphene, 23 they need to be functionalized with functional groups or biomolecules 24 for inducing HAp nucleation.…”