Sol?gel synthesis and in vitro bioactivity of tricalcium silicate powders

Tricalcium silicate (Ca3SiO5) powders were synthesized by sol–gel process with Ca(NO3)2·4H2O and Si(OC2H5)4 (TEOS) as the starting materials. Pure Ca3SiO5 could be obtained at 1400 °C and above. The in vitro bioactivity of tricalcium silicate was investigated by soaking the powders in simulated body fluid (SBF) for 10 days. The surface compositional, morphological and structural changes of the powders before and after soaking were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that a dense hydroxyapatite (HAp) layer was formed after 10 days of soaking. Our results indicated that tricalcium silicate was bioactive and might be used for preparation of implantable biomaterials.