الفهرس 
ContentsOnly 14 pages are availabe for public view
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Abstract
This study aimed to prepare two systems with different concentration of phosphate, borate and titanium oxide. In the first system it is intended to control the rate of dissolution and glass bioactivity By substituting P2O5 with TiO2 progressively in the composition 0.07P2O5 – 0.46 B2O3 - 0.24 CaO – 0.23 Na2O and TiO2. The second system have a composition 0.50 P2O5 – 0.20 B2O3 - 0.20 CaO – 0.10 Na2O - xTiO2, (with x = 0.0, 0.02, 0.04, 0.06 mol%). The systems were prepared by fast quenching, then the prepared glasses were characterized using density measurements, X-ray diffraction (XRD), differential thermal analysis (DTA) and scanning electron microscopy (SEM). The bioactivity of the glasses were studied through carrying out solubility tests by immersing the glass in simulated body fluid (SBF) solution and examining the formation of hydroxyapatite (HA) layer on the surface of the glass by XRD, SEM and Fourier transform infrared (FTIR) spectral analyses. Sum biomedical properties of systems were studied such as anticancer activity using MTT assay by flow cytometry and phase contrast microscope. The results showed an increase in density and a decrease in molar volume, which indicates creating non bridging oxygen (NBO) and TiO2 acts as a modifier. The results showed a decrease in pH and weight loss with increasing the TiO2 content which act as a nucleating agent. The spectroscopy analysis of glass after immersed in SBF solution emphasize the formation of a crystalline HA on the surface of the samples and assures that by the ratio of CaO to P2O5 in EDX which indicates a bioactivity of glass. FTIR explain that BO3 is converted to BO4 in the borate glass structure and the phosphate group symmetric stretching O-P-O bending modes of the Q0 units and assigned to Q2 tetrahedral structure vibration. The glass was investigated against normal and cancerous cell lines of liver, breast, colon and prostate. The second system( specially the sample which doped with 0.06 mol % TiO2) had a harmless effect on human normal cells and exhibited the highest enhanced anticancer activity against all tested human cancer cells to be more than 80%. The necrosis-dependent anticancer mechanism of TiO2 was declared by the high percentage of propidium-iodide stained cancer cell population using flow cytometry.