Structural and in vitro biological properties of strontium substituted bio-waste derived wollastonite for bone regeneration.

Strontium (Sr) substituted wollastonite bioceramics were prepared by a modified sol-gel technique using bio-wastes such as eggshell as calcium oxide source and rice husk as silica source. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and Scanning electron microscopy-energy dispersive spectrometer (SEM-EDS) were used to perform structural analysis. Bioactivity was examined by testing the apatite mineralization ability in vitro by immersing the ceramic pellets in simulated body fluid (SBF) for various time periods. Degradation assay was performed in Tris buffer solutions by following the protocol in ISO 10993-14 standard. Cytocompatibility and cell proliferation were analyzed at different concentrations using osteoblast like MG 63 cells by MTT assay. The results show that the addition of Sr increases the density and mechanical properties of wollastonite but decreases with SrO above 2.5 mol.%. Pure and Sr containing wollastonite possessed excellent apatite formation ability with continuous degradation under physiological conditions. The results of cell culture studies revealed that all prepared ceramics were non-toxic to osteoblast-like cells at different doses (0–1000 μg/mL), and wollastonite ceramics containing Sr also enhanced cell proliferation. [ABSTRACT FROM AUTHOR]