A preliminary investigation into the structure, solubility and biocompatibility of solgel SiO2-CaO-Ga2O3 glass-ceramics

The proposed study aims to synthesize gallium (Ga3+) containing glass-ceramics via the solgel method and determine their solubility and biocompatibility. Three solgel derived glass-ceramics, two containing Ga3+ were synthesized by substituting 5 mol% Ga3+ for both Ca2+ (Si-65) and Si4+ (Si-70) and were compared to a Ga3+ free control (control). Glass transition temperatures (Tg) ranged from 641 to 660 °C for all materials with particle sizes ranging between 1.5 and 2.5 μm. Surface area analysis ranged from 45 to 55 m2 g−1 and any changes in pH were determined over 0-14 days. Ga3+ ion release from Si-65 peaked at 433 mg L−1 after 7 days, and Si-70 peaked at 601 mg L−1 after 1 day. Both calcium (Ca2+) and silica (Si4+) were also released from each material. Antibacterial testing against E. coli and S. epidermidis revealed both bactericidal (maximum inhibition zone of 2.5 ± 0.3 mm) and bacteriostatic effects. The control material exhibited inhibition zones in both bacteria while bacteriostatic properties were found predominantly against E. coli with Si-65 and Si-70. Cytocompatibility testing was conducted in L929 mouse fibroblasts and determined no significant reduction in cell viability with respect to the control, with minimal, non-significant reductions for Si-65 and Si-70.