Incorporation of trace elements into calcium phosphate structure is of great interest for the development of artificial bone implants. Biphasic calcium phosphate (BCP) composed of hydroxyapatite (HA) and β-tricalcium...Incorporation of trace elements into calcium phosphate structure is of great interest for the development of artificial bone implants. Biphasic calcium phosphate (BCP) composed of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) have been synthesized in the presence of magnesium (5 M% - 20 M%) by gel method under physiological conditions. Crystallization of Mg-BCP in the gel medium mimics the Mg intake in the human body. Powder X-ray dif- fraction and Fourier transform infrared analyses confirmed that the Mg doping leads to the enrichment of β-TCP phase and suppresses the HA content in BCP. Nanoindentation studies indicate a significant decrease in hardness and elastic modulus values of BCP due to Mg doping. In vitro bioactivity study has confirmed the formation of apatite layer on the Mg doped samples making it suitable for bone replacement. The results suggest that the optimum Mg doping promotes the bioactivity which is perquisite for biomedical applications.展开更多
Calcium hydrogen phosphate dihydrate (CHPD, CaHPO4· 2H2O) or brushite is found quite frequently in urinary calculi (stones). Crystallization of brushite has been carried out in sodium metasilicate (SMS) gel with ...Calcium hydrogen phosphate dihydrate (CHPD, CaHPO4· 2H2O) or brushite is found quite frequently in urinary calculi (stones). Crystallization of brushite has been carried out in sodium metasilicate (SMS) gel with and without adding ‘Sr’ as additive. In pure system, dicalcium phosphate anhydrous (DCPA, CaHPO4) or monetite and hydroxyapatite (HA, Ca5(PO4)3(OH)) grew along with brushite. The presence of Sr suppressed the formation of HA and enhanced the number and size of monetite crystals and changed the morphology of brushite crystals from needle shape to octopus-like shape. The samples were characterized by powder & single crystal X-ray diffraction (XRD), scanning electron microscopy (SEM), Xray fluorescence spectroscopy (XRF), Fourier transform infrared spectroscopy (FTIR) and thermal analyses (TG-DTA).展开更多
文摘Incorporation of trace elements into calcium phosphate structure is of great interest for the development of artificial bone implants. Biphasic calcium phosphate (BCP) composed of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) have been synthesized in the presence of magnesium (5 M% - 20 M%) by gel method under physiological conditions. Crystallization of Mg-BCP in the gel medium mimics the Mg intake in the human body. Powder X-ray dif- fraction and Fourier transform infrared analyses confirmed that the Mg doping leads to the enrichment of β-TCP phase and suppresses the HA content in BCP. Nanoindentation studies indicate a significant decrease in hardness and elastic modulus values of BCP due to Mg doping. In vitro bioactivity study has confirmed the formation of apatite layer on the Mg doped samples making it suitable for bone replacement. The results suggest that the optimum Mg doping promotes the bioactivity which is perquisite for biomedical applications.
文摘Calcium hydrogen phosphate dihydrate (CHPD, CaHPO4· 2H2O) or brushite is found quite frequently in urinary calculi (stones). Crystallization of brushite has been carried out in sodium metasilicate (SMS) gel with and without adding ‘Sr’ as additive. In pure system, dicalcium phosphate anhydrous (DCPA, CaHPO4) or monetite and hydroxyapatite (HA, Ca5(PO4)3(OH)) grew along with brushite. The presence of Sr suppressed the formation of HA and enhanced the number and size of monetite crystals and changed the morphology of brushite crystals from needle shape to octopus-like shape. The samples were characterized by powder & single crystal X-ray diffraction (XRD), scanning electron microscopy (SEM), Xray fluorescence spectroscopy (XRF), Fourier transform infrared spectroscopy (FTIR) and thermal analyses (TG-DTA).
