In Vitro antibacterial activity of Ta2O5 doped glass-ceramics against pathogenic bacteria

Highlights: • Antibacterial activity against all gram positive bacteria observed. • Antibacterial activity independent of high pH value of the supernatant. • Addition of Ta₂O₅ to Bioglass^® exerted antibacterial ability to bioactive Bioglass^® composition. • Leaching of Ta⁺⁵ ions from the specimen surface exerts hyper-osmotic environment which inhibited bacteria. The use of synthetic implants for restoration of damaged or diseased bone is associated with risk of bacterial colonization that result in failure of the implant. It is essential for implants to make bond with bone and soft tissue without bacterial infection. The present study is based on evaluation of the antibacterial property of Ta₂O₅ doped novel glass ceramics having a chemical composition (40-x) SiO₂-24.4Na₂O-26.9 CaO-6.1CaF₂-2.6P₂O₅-xTa₂O₅ where x = 0, 0.1, 0.5, 1 and 3 mol %. In Vitro antibacterial assays were performed in dark against six common pathogenic bacterial strains; Strep. pyogenes, B. subtilis, Staph. epidermidis, E. coli, Proteus. mirabilis and Pseudomonas. aeruginosa using modified Kirby Bauer method. It was observed that all samples doped with Ta₂O₅ showed statistically significant (P < 0.05) antibacterial activity against all three gram positive bacteria; independent of high pH value of the supernatant. Sample doped with 3 mol% Ta₂O₅ demonstrated strongest antibacterial effect, which may be attributed to high concentration of Ta⁺⁵ ions observed in the supernatant (SBF). The antibacterial activity of Ta₂O₅ doped Glass ceramics was prone to initial leaching of high ionic strength Ta⁺⁵ ions from the specimen surface to supernatant that exerts hyper-osmotic environment which inhibited bacteria. Therefore, it can be concluded that addition of Ta₂O₅ to Glass ceramics exerted antibacterial ability to bioactive Glass ceramics composition.