Sol-Gel Derived Bioactive Glasses as Synthetic Bone Substitutes

Bioactive glasses based on the SrBGs: 45SiO2 - 6P2O5 - 15SrO - 34CaO, 5Zn-SrBGs (wt.%): 45SiO2 - 6P2O5 - 15SrO - 29CaO - 5ZnO (wt.%), and 5Ce-SrBGs: 45SiO2 - 6P2O5 - 15SrO - 29CaO – 5CeO (wt.%) were successfully synthesised through the sol-gel process under the acid condition. The concentration of nitric acid at 0.01M was an optimal condition to accelerate the hydrolysis and polycondensation reactions in these systems. SEM images showed the primary particle nucleus growth in the morphological structure of the SrBGs, 5Zn-SrBGs, and 5Ce-SrBGs. FTIR spectra indicated the incorporation of therapeutic cations in the glass structure whilst maintaining the morphological structure. XRD and SEM suggested the crystalline apatite formation on the surface of BGs after the BGs were incubated in the simulated body fluid (SBF) at pH 7.4 for 21 days. EDS-SEM indicated the apatite formation whilst containing doping ions in the glass structure. All three BGs formulations could promote the murine pre-osteoblast cell (MC3T3-E1) cell proliferation at the concentration between 200-250 µg/mL and have no in vitro cytotoxicity on MC3T3-E1 cells up to the concentration of 1mg/mL.