Facile synthesis and in vitro bioactivity of radial mesoporous bioactive glass with high phosphorus and calcium content

A novel uniform monodispersed radial mesoporous bioactive glass nanosphere (MBG) with high phosphorus and calcium content has been successfully synthesized. The synthesis was first taken place in a cyclohexane-water biphasic stratification reaction system, which fabricated the radial mesoporous SiO₂-P₂O₅ nanosphere (SPN) using hexadecyltrimethyl ammonium bromide (CTAB) as a template agent and triethanolamine (TEA) as a hydrolysis catalyst. Solid reactions were then carried out to synthesize SiO₂-CaO-P₂O₅ MBG using SPN as both the silicon source and phosphorus source, and Ca(NO₃)₂ as the calcium source. The prepared MBG not only displayed the radial structure and high specific surface area (~321 m²/g), but also had high phosphorus and calcium content. The results of energy dispersive spectrometer (EDS) demonstrated that P₂O₅ content was enhanced by properly increasing the reaction temperature. The in vitro bioactivity test showed that MBG had an excellent ability of inducing apatite formation. Furthermore, the MBG showed excellent biocompatibility at a low concentration of 50–100 μg/mL in vitro, and it would have a promising prospect as drug delivery system for bone tissue regeneration.