Options
Structure and biocompatibility of hydroxyapatite film synthesized by concurrent plasma sputtering
Author
Sim, Lina Lu Ping
Supervisor
Xu, Shuyan
Abstract
Bioactive Hydroxyapatite (HA)-coated implants has recently attracted increasing interest due to their excellent biocompatibility for dental and orthopaedic applications. In this work W magnetron HA+Ti concurrent sputtering deposition technique is employed to synthesize HA onto Ti6AL4V substrate.
The elemental composition of the bioceramic thin film is analyzed by the energy dispersive x-ray (EDX). Results show that the CalP ratio decreases with increasing pressure and on the other hand, increases with increasing bias voltage. Raman and Fourier transform infrared (FTIR) spectroscopy have also presented typical P043bonds, confirming the presence of HA in the thin film.
Field emission scanning electron miicroscope (SEM) and x-ray diffractometry (XRD) are used to study the morphology and structure of the HA coating. From SEM and EDX, it is observed that there is higher content of HA with increasing temperature. This is substantiated by XRD analysis. The crystalline HA grows steadily on the preferred orientations of the (21 1) and (1 12) planes. Further investigation of the crystallization process is performed by varying the time during deposition. Both XRD and SEM reveal that the HA crystallites increase in content and become larger with longer deposition time.
Finally. in vitro assessments are performed using the devised HA thin film. The evaluations include using the Simulated Body Fluid (SBF) and bone cell culture method. It is demonstrated that the HA-coated sample is remarkably biocompatible. Nucleation process starts after 12hrs of immersion in SBF and compact nano-scale apatite granules are observed to grow steadily after 48hrs of immersion. Moreover, bone cell culture assessment has also revealed the excellent cytocompatibility of the HA coating. Osteoblast cells are observed to have proliferated, attached, differentiated and grow to form bone nodules and mineralized extracellular matrix after eight days culture.
The elemental composition of the bioceramic thin film is analyzed by the energy dispersive x-ray (EDX). Results show that the CalP ratio decreases with increasing pressure and on the other hand, increases with increasing bias voltage. Raman and Fourier transform infrared (FTIR) spectroscopy have also presented typical P043bonds, confirming the presence of HA in the thin film.
Field emission scanning electron miicroscope (SEM) and x-ray diffractometry (XRD) are used to study the morphology and structure of the HA coating. From SEM and EDX, it is observed that there is higher content of HA with increasing temperature. This is substantiated by XRD analysis. The crystalline HA grows steadily on the preferred orientations of the (21 1) and (1 12) planes. Further investigation of the crystallization process is performed by varying the time during deposition. Both XRD and SEM reveal that the HA crystallites increase in content and become larger with longer deposition time.
Finally. in vitro assessments are performed using the devised HA thin film. The evaluations include using the Simulated Body Fluid (SBF) and bone cell culture method. It is demonstrated that the HA-coated sample is remarkably biocompatible. Nucleation process starts after 12hrs of immersion in SBF and compact nano-scale apatite granules are observed to grow steadily after 48hrs of immersion. Moreover, bone cell culture assessment has also revealed the excellent cytocompatibility of the HA coating. Osteoblast cells are observed to have proliferated, attached, differentiated and grow to form bone nodules and mineralized extracellular matrix after eight days culture.
Date Issued
2004
Call Number
TK7871.15.F5 Sim
Date Submitted
2004