Preparation and antibacterial property on silver incorporated mesoporous bioactive glass microspheres

Abstract

In this study, the antibacterial property of silver-incorporated mesoporous bioactive glass microspheres (Ag-MBGMs) was investigated. The samples belonging to the 80SiO2·(15 − x)CaO·5P2O5·xAg2O system where 0 ≤ x ≤ 5 mol% were successfully prepared for bone regeneration and drug carrier applications. The obtained samples were evaluated by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope, Fourier transform infrared spectroscopy, and N2 adsorption/desorption measurements. All Ag-MBGMs had spherical particles with particle size 6–10 µm. TEM images showed mesopore structure. The textural properties showed a decrease in surface area and pore volume with an increase in silver content. XRD patterns exhibited the presence of pseudowollastonite and hydroxyapatite phase for silver-incorporating MBGMs, which might increase its bioactivity and bone bonding ability. Finally, all Ag-MBMGs had an antibacterial effect against both Escherichia coli and Staphylococcus aureus. Therefore, Ag-MBGMs may provide more potential for use as injectable, anticancer and drug-loading biomaterials for bone tissue engineering applications. In this study, the mesoporous bioactive glass microspheres (MBGMs) belonging to the system 80SiO2·(15 − x)CaO·5P2O5·xAg2O (x = 1, 3, and 5) were successfully prepared by the sol–gel process with surfactant-assisted mesoporous template. Effects of silver addition in MBGMs system were investigated for the first time such as particle shape and size, textural analysis, phase composition, in vitro bioactivity, and antibacterial effect. All prepared MBGMs have uniform microspherical particle (2–5 µm) with hierarchically structure. The textural analysis revealed that all prepared MBGMs had high porosity and relatively high surface area. The incorporation of apatite, pseudowollastonite, and metallic silver crystals were found for adding silver content more than 1 mol%. All prepared MBGMs can induce the crystalline hydroxyl carbonate apatite layer on the surface after soaking in simulated body fluid solution for 7 days. All silver-containing MBGMs had a very good antibacterial effect against Staphylococcus aureus and Escherichia coli. In addition, silver-incorporated MBGMs exhibited anticancer property against HepG2 cells.