Papers by Author: Mei Wei

Abstract: Bone-like apatite coatings were prepared using a biomimetic method in a simulated body fluid (SBF). The effect of initial pH values on the surface morphology of biomimetic apatite coating was studied. The coatings were characterized using X-ray diffraction and environmental scanning electron microscope. It was revealed that the morphology of the biomimetic apatite coating could be tailored by manipulating the initial pH of the SBF solution.

Abstract: Fluoridated hydroxyapatite (FHA) discs with various fluorine contents have been used to study the effect of fluorine content on early-stage cell behavior. FHA powders with fluorine content in the range 0-0.577 (mol F /mol apatite) were pressed into discs and sintered at 1200°C for 1 hour. SAOs-2 rat osteosarcoma cells were cultured on each FHA disc and tissue culture polystyrene (control) with the same seeding density for 4 hours. The cell count was conducted using Alamarblue, and the morphology of cell attachment was observed using environmental scanning electron microscopy. It was apparent that the fluorine content in FHA had significant impact on the early cell behavior.

Abstract: This paper reports the influence of aging time and reaction temperature on the surface morphology and mechanical properties of hydroxyapatite (HA) synthesized by a hydrothermal method. Calcium nitrate and ammonium orthophosphate solutions were premixed and fed to an autoclave and reacted to temperatures varying between 25-250°C for 2-10 h. Results indicate the strong positive influence of reaction temperature on the HA particle aspect ratio. The density of the discs pressed from these samples reached 85-90% of the theoretical density after calcination at 1200°C for 1 h. Sintered density and flexural strength were found to increase with increasing aging time and reaction temperature. A maximum flexural strength of 78 MPa was observed for the sample synthesized at 170°C for 5 h with the predicted average at these conditions being 65 MPa.