Investigation of the physico-chemical reactivity of a mesoporous bioactive SiO2-CaO-P2O5 glass in simulated body fluid

A new mesoporous bioactive glass (MpBaG) based on SiO2-CaO-P2O5 by the sal-gel method has been successfully synthesized for biomedical applications. The obtained material was evaluated by thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and N-2 adsorption analysis. The N-2 adsorption isotherm analysis showed that the pores were in mesopore size range and the MpBaG presented a specific surface area 137.9 m(2) g(-1) and a median pore size 15.4 nm. The surface reactivity of the MpBaG was studied in vitro in simulated body fluid (SBF). Inductively coupled plasma-atomic emission spectrometry (ICP-AES), SEM, EDS, XRD and FTIR were used to characterize the MpBaG surfaces and the SBF compositional changes. Immediately after immersion in SBF, reactions occurred on the surface of MpBaG. It is notable that the obtained results from FTIR and XRD analyses showed all typical characteristic peaks of bone-like hydroxyapatite (HAp). Also, it was obvious that the other new peaks after immersion in SBF were certainly related to the formation of hydroxycarbonate apatite (HCAp) and carbonate calcium (calcite). Finally, this research demonstrated that the synthesized MpBaG is a nontoxic and biocompatible material for ongoing osteogenic studies in segmental defects in the goat model in vivo. (C) 2010 Elsevier B.V. All rights reserved.