Unscrambling the Influence of Sodium Cation on the Structure, Bioactivity, and Erythrocyte Compatibility of 45S5 Bioactive Glass

The 45S5 bioglass uttering Class A bioactivity promotes both osteoconduction as well as osteoinduction. Though one of the higher reactive bioactive materials known with structural and physiological influence upon ionic modulation, poor mechanical properties are perceived. The possible solution to overcome the weak stability is to choose material’s composition that provides retained bioactivity and improved mechanical stability. Meanwhile, primary burst out of Na⁺ ions increases the local pH, harms cell life, and acts as a well-known disruptive modifying species that weakens the bioactive glass network, decreasing network connectivity, showing faster degradation and lowering mechanical stability. Therefore, in this study, more detailed systematic exploration on structural influence of sodium monovalent cation and its behavior on physiological environment was genuinely studied and reported that bioactivity of the bioactive glass can be highly achieved even without Na⁺ ions. The result exhibits benefits of sodium free bioactive glass (denoted as No Na⁺ BG) over Na⁺ BG and exhibits improved mechanical stability and also possible degradability, having in-built apatite phase even before immersion in simulated body fluid (SBF). Also, sodium free bioglass proved as a superior candidate for erythrocyte compatibility with rapid clotting tendency on interaction with blood and a promising replacement for 45S5 bioglass in all aspects especially in mechanical stability view, which can withstand more than 5 months in phosphate buffer saline (PBS).