Structural characterization, in vitro bioactivity, and antibacterial evaluation of low silver-doped bioactive glasses

Four bioactive glasses (70 SiO2-(20-X) CaO-10 P2O5) containing low concentrations of silver (X Ag2O; where X = 0.5, 1, and 1.5 mol%) were synthesized by the conventional sol-gel method. Physical and structural characterization was realized using Fourier Transform Infrared (FT-IR), Thermogravimetric Analysis (TGA), X-ray Diffraction analysis (XRD), and Scanning Electron Microscopy (SEM-EDX). Acellular bioactivity tests were performed by immersion in the SBF solution. Escherichia coli and Staphylococcus aureus were used to evaluate the antibacterial activity of the prepared Ag-doped bioglasses. While FTIR, DRX, and SEM analysis displayed good acellular bioactivity for all bioactive glasses (Ag-70S), the antibacterial activity confirms well the bactericidal effect of 70S 1Ag and 70S 1.5Ag through total growth inhibition (100%) of the two pathogenic bacteria. It is also important to mention that low silver-doped bioglass nanoparticles (Ag2O <= 1.5 mol%) could be a required multifunctional candidate in bone tissue engineering.