Use of acetic acid to prepare mesoporous bioactive glass capable of silver delivery for antibacterial applications

Mesoporous bioactive glass with the mole ratio of 60SiO2:36CaO:4P2O5 was prepared using acetic acid (HAc-M58S) and hydrochloric acid (HCl-M58S). The HAc-M58S exhibits high drug-loading capacity and longer drug-release time. The drug-release performance of the HAc-M58S and HCl-M58S were studied by loading them with silver and then releasing the silver into simulated body fluid. The results showed that the specific surface area, pore volume, and average pore size of the HAc-M58S were 221.6 m2 g−1, 0.45 cm3 g−1, and 8.5 nm, respectively, all of which were superior to HCl-M58S (203.4 m2 g−1, 0.36 cm3 g−1, and 7.2 nm, respectively). Furthermore, the silver-loading capability of the HAc-M58S was 19%, which corresponded to an increase of about 31% over that of HCl-M58S. In addition, the release rate of the HAc-M58S was 0.82%, which is lower than that of the HCl-M58S, at 1.07%. The zones of inhibition of the silver-loaded HCl-M58S and HAc-M58S had an average size of 10.57 mm and 12.26 mm, respectively. In-vitro bioactivity tests revealed that the HAc-M58S exhibited good biological activity. Therefore, the HAc-M58S, given its higher silver-loading capacity and longer silver-release time, is a promising candidate drug carrier.