Papers by Author: S.P. Singh

Abstract: The Aim of this Work Is to Investigate Role of Iron in Calcium-Iron-Phosphate Bioglass. the Density, Compressive Strength, Tg Point and Leachability of Cations Were Measured. the Ph Behaviour of Simulated Body Fluid after Soaking Phosphate Glasses for Different Time Periods Were Also Studied and it Was Observed that Higher Phosphate Glasses Containing Lower Lime Possessed Better Bioactivity than Lower Phosphate Glasses Containing More Iron and Lime Contents. the DTA and FTIR Spectrometry of Glasses Were Performed. the Absorption Spectra Showed that Iron Was Present in the Glass only as Fe3+ Ion. the Leachability of Ca2+ and Fe3+ Ions from Glass Was due to Diffusion Control and P5+ Ion due to Network Break down of PO4 Tetrahedra. the DTA Peaks Were Broad. the FTIR Band around 1000 Cm-1 in Glass Was due to Asymmetric Stretching of O=P=O Linkage. the FTIR Absorption and Reflectance Spectrometry of the Glass Samples after SBF Treatment Had Confirmed the Deposition of Bone-Like Hydroxyl Carbonate Apatite Layer on the Glass Surfaces for their Bioactivity. the Bands Centred in between 2880-3425 Cm-1 Were due to Presence of OH Groups and Stretching Modes of H-O-H Vibration in Glasses. the Properties and Structure Relationship for Glasses Were Established and the Results Were Discussed.

Abstract: Bioglass Ceramics having molar composition 40SiO2-(44-X)CaO-10MgO-6P2O5-XCaF2 (where X = 0 to 8%) were prepared by conventional melting process in an electric globar furnace at 1400±10°C. Controlled crystallizations were carried out to convert the bioglasses to their corresponding ceramics. Nucleation and crystallization regimes were carried out by differential thermal analysis. The crystalline phases termed hydroxy fluoroapatite, akermanite and wollastonite were identified by using x-ray diffraction analysis. The investigation of bioactivity for the prepared glass and glass ceramics was done by infrared absorption and infrared reflection spectra after immersion in simulated body fluid (SBF) for different periods at 37.8°C. Scanning electron microscope (SEM) analysis was carried out to investigate the surface texture. Micrographs show the formation of HCA layer on the surface of the bioglass ceramics samples after 7 days of SBF treatment. The surfaces of the samples were completely covered with irregular and needle-like aggregates of Ca–P layer. The released ions were estimated by atomic absorption spectroscopy. The chemical durability of these materials was determined by pH measurement methods and it was found that pH of the solution increases up from 1 to 7 days. Further, pH decreases with increasing time period, from 15 to 30 days in SBF solution.