Synthesis and in vitro bioactivity of strontiumcontaining bioactive glass-ceramic/starch composite as a potential scaffold for bone regeneration

The ability of bioactive glass/polymer and glass-ceramic/polymer composites to elicit bone bonding reactions, accompanied by degradability, when used as implants, without provoking adverse immune responses, makes them attractive biomaterials for bone regeneration. More efforts are being devoted to synthetic strategies to make the process cost-saving and more appealing for commercial production. Against this backdrop, we synthesised and studied the bioactivity of a bioactive glass-ceramic/polymer composite with the glass composition of SiO2–CaO–SrO–P2O5. A solution precipitation approach was used to obtain the bioactive-ceramic from sodium metasilicate (Na2SiO3.9H2O) as a low-cost silica alternative to alkoxysilane precursors, which was used afterwards as a filler phase in a starch-based matrix. An in vitro bioactivity experiment was conducted to determine the hydroxyapatite-inducing capacity of the samples in simulated body fluid for 7–14 days. Thereafter, the samples were characterised with scanning electron microscopy, energy dispersive x-ray analysis, x-ray diffractometry and Fourier transform infrared spectroscopy. Results obtained showed that the bioactive glass-ceramic composite exhibited superior morphological characteristics, higher bioactivity and degradability compared with the pristine sample. The strontium-based bioactive glass-ceramic/starch composite possesses promising characteristics that could make it a potential scaffold for bone regeneration. Hence, sodium metasilicate can be considered a viable and low-cost substitute for alkoxysilanes in the production of strontium-doped bioactive glass/polymer composites.