Preparation and characterization of spray pyrolysized strontium-silver-doped mesoporous bioactive glass micron spheres

Mesoporous bioactive glass (MBG) is a remarkable biomaterial for biomedical applications due to its excellent specific surface area, bioactivity, and biocompatibility. By adjusting doped ions used in bioactive glasses (BGs), the properties along with the changes of biological responses can be controlled. For the purpose of safe and effective effects on bone regeneration and formation, strontium (Sr) is selected as a doped ion source in BGs to induce promising biological responses. Due to difficulties to detect osteoporosis in the early phase, the clinic solution is orthopedic surgery. However, there are several cases of bacterial infection called surgical site infection. Thus, a biomaterial with the ability against bacterial activity and able to promote osteoblast cells for bone regeneration is critical and needed. There have been reports that metal ion–doped BG particles can activate a high inhibitory effect on bacterial growth. In this work, MBG microspheres were fabricated using the spray pyrolysis method with the addition of silver (Ag) together with Sr as the dopant. The phase information and particle morphology were evaluated by X-ray diffractometer and field emission scanning electron microscope, respectively. The antibacterial test was conducted using the bacteria colony counter method. The cell viability was investigated by MTT assay. In vitro bioactivity was investigated based on Kokubo’s protocol. The pure and doped MBG particles were characterized by X-ray diffraction to determine the growth of the hydroxyapatite layer in simulated body fluid solution. Finally, the observations reveal that the Sr- and Ag-doped MBG powders enhanced the antibacterial capability, cell viability, and hydroxylapatite formation rate.