Investigation on silver doped B2O3 - SiO2 - P2O5 - Na2O - CaO bioglass system for biomedical applications

The borate based bioactive glasses doped with Ag2O are synthesized using melt quenching technique. In vitro bioactivity studies of these glasses are carried out as a function of Ag2O content. The glasses of the chemical composition 43B2O3-5SiO2 -2P2O5-20Na2O- (30-x) CaO: x Ag2O with 0 ≤ x ≤ 2, are obtained by conventional melt quenching technique and are characterized by FTIR, UV- vis-absorption and X-ray diffraction techniques. Physical properties such as density, molar volume, oxygen packing density and silver ion concentration are also evaluated. The data obtained indicated that these parameters are affected by the silver oxide content. Results from FTIR, UV-vis.-spectroscopy studies indicated that Ag2O acted as a network modifier, by converting boron atoms from three coordinated to four coordinated with oxygens. Simulated body fluid (SBF) solution is used to test the in vitro bioactivity of the pure and silver doped glasses. Scanning electron microscopy (SEM) is used to investigate the surface morphology of the samples. Moreover, SBF treated samples are characterized by FTIR, XRD techniques in order to verify their bioactivity as a function of Ag content. The solubility test data indicated that a clear increase of degradability of glass with increase of Ag2O content. The results obtained from XRD, FTIR pointed out that the increase of Ag2O content enhanced the ability of formation of hydroxyapatite (HA) layer on the surface of the samples.