Role of magnesium and aluminum substitution on the structural properties and bioactivity of bioglasses synthesized from biogenic silica

The objective of this study was to investigate the effect of magnesium(1 wt%)and aluminum(1 wt%)incorporation on the in vitro bioactivity and biodegradation behavior of 45S5 bioactive glasses synthesized from rice husk biogenic silica.The performance of biogenic silica-based samples was compared well with commercial silica-based counterparts.The in vitro biodegradation behavior of bioactive glasses was evaluated by the weight loss of samples and pH variation in the Tris buffer solution.Based on composition,bioglasses possessed different properties before and after simulated body fluid(SBF)immersion.The incorporation of magnesium(Mg)and aluminum(Al)enhanced the Vickers hardness of bioglasses.All the bioglasses showed the hydroxyapatite layer formation after SBF treatment as confirmed by the dissolution,FTIR,SEM and XRD analysis,however it was more prominent in the rice husk silica-based 45S5 bioglass.The biogenic silica seems to be a promising starting material for bioglass systems to be used in bone tissue engineering applications.