The significant impact of the change in the chemistry of bioactive glass on structural morphology in buffered saline solution

In this study, bioactive glass (BG) with varying concentration of chemical constituents was synthesized via sol-gel process and investigated by comparing before and after immersion in buffered saline solution with a combination of XRD, SEM, and FTIR, alongside pH, and Ca/P analysis. By immersion, value of pH increase from 8.8 to 10.2, which enhanced the precipitation of mineral layers. Rapid ion exchange and increased alkalinity (pH ~ 9.9) were observed for low-silica compositions (less than 50 wt%), causing the development of disordered Ca-rich phases. The newly formed surface confirms a 1.64 Ca/P ratio in BG3 (55 wt% SiO 2 ) compositions by EDS analysis, matching the stoichiometry of natural bone mineral. XRD analysis reveals a significant increase in mineral density, which is confirms by peak intensities at 45.68° that increases by 80% between 14 and 28 days of immersion. These outcomes demonstrate that a larnite-rich environment and controlled silica content (up to 75 wt%) effectively regulate ion exchange. These findings highlight a well-defined framework to optimize glass-ceramic composite for bone tissue engineering.