Highly-Bioreactive Silica-Based Mesoporous Bioactive Glasses Enriched with Gallium(III).

Beneficial effects in bone cell growth and antibacterial action are currently attributed to Ga ions. Thus, they can be used to upgrade mesoporous bioactive glasses (MBGs), investigated for tissue engineering, whenever they released therapeutic amounts of gallium ions to the surrounding medium. Three gallium-enriched MBGs with composition (in mol %) SiO₂-CaO-P₂O₅-5Ga₂O₃, being = 70, = 15, = 10 for ; = 80, = 12, = 3 for ; and = 80, = 15, = 0 for , were investigated and compared with the gallium-free 80SiO₂-15CaO-5P₂O₅ MBG (). Si and P MAS NMR analyses indicated that Ga acts as network modifier in the glass regions with higher polymerization degree and as network former in the zones with high concentration of classical modifiers (Ca ions). and exhibited a quick in vitro bioactive response because they were coated by an apatite-like layer after 1 and 3 days in simulated body fluid. Although we have not conducted biological tests in this paper (cells or bacteria), released high but non-cytotoxic amounts of Ga ions in Todd Hewitt Broth culture medium that were 140 times higher than the IC90 of bacteria, demonstrating its potential for tissue engineering applications.