Nanometer Coatings of Hydroxyapatite Characterized by Glancing-Incidence X- Ray Diffraction

Abstract

Hydroxyapatite (HAP) crystalline thin-coatings have been grown using a right angle RF magnetron sputtering approach at room temperature. The surface structural information of these biocompatible coatings at nanometer scales was obtained by glancing-incidence X-ray diffraction (GIXRD) with synchrotron radiation. The GIXRD spectra were obtained by fixed incidence theta angles at 0.5 and 1 degree. Structural profile analyses were performed over these nano-coating layers with reduced substrate interference. The coating thickness was calibrated by specular X-ray reflectivity (XRR) curves. Experiments have been performed on thin-coatings of HAP sputtered on silicon wafers and acid etched titanium discs at room temperature. GIXRD analysis has shown that all the principal peaks are attributed to a crystalline HAP. Previous tests of biocompatibility with osteoblasts cells have been encouraging studies on the surface of hydroxyapatite thin coatings prepared by opposing RF magnetron sputtering approach, as a promising candidate for bioimplant materials.

Adsorption and bioactivity studies of albumin onto hydroxyapatite surface

“…This behavior was characteristic of needle shape particles with crystal growth along the HA c direction. That crystalline preferential orientation along the surface was also observed in nanometric thin films of HA deposited onto silicon substrates [27].…”

Nanodimensional and Nanocrystalline Calcium Orthophosphates

“…Application of both ultrasound [362,[459][460][461] and viscous systems [462] might be helpful. Furthermore, nanodimensional HA might be manufactured by a laser-induced fragmentation of HA targets in water [463][464][465][466][467] and in solvent-containing aqueous solutions [344,371,468], while dense nanocrystalline HA films might be produced by radio frequency magnetron sputtering [469,470]. An interesting approach using sitting drop vapor diffusion technique should be mentioned as well [471].…”

Nanodimensional and Nanocrystalline Apatites and Other Calcium Orthophosphates in Biomedical Engineering, Biology and Medicine

“…Continuous preparation procedures are also available [ 185 , 361 ]. Furthermore, nanodimensional HA might be manufactured by a laser-induced fragmentation of HA microparticles in water [ 362 , 363 , 364 ] and in solvent-containing aqueous solutions [ 297 , 313 , 365 ], while dense nanocrystalline HA films might be produced by radio frequency magnetron sputtering [ 366 , 367 ]. A comparison between the sol-gel synthesis and wet chemical precipitation technique was performed and both methods appeared to be suitable for synthesis of nanodimensional apatite [ 288 ].…”