Novel antibacterial Cu/Mg-substituted 58S-bioglass: Synthesis, characterization and investigation of in vitro bioactivity

In this study, six sol-gel copper/magnesium substituted derivatives of 58S-BG, that is, a mol% series of 60SiO(2)-4P(2)O(5)-5CuO-(31-x) CaO/xMgO (where x = 0, 1, 3, 5, 8, and 10), were synthesized as new multifunctional bioactive glasses (BGs). Afterwards, the effect of MgO/CaO substitution on the in vitro formation of nanohydroxyapatite (HA), osteoblast-like cell responses, and bioactive glasses antibacterial performance were studied. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) results revealed that Cu-substituted 58S-BG consisting of 5 mol% MgO (BG-5/5) had capability of the formation of HA on its surface while, Cu-substituted 58S-BGs consisting 8 mol% and 10 mol% MgO (BG-5/8 and BG-5/10) displayed lower bioactivity. The In vitro investigations proved that the highest values of both differentiation and proliferation of MC3T3-E1 cells can be obtained from a 5 mol% MgO substituted BG. Furthermore, these novel Cu/Mg-substituted 58S-BGs displayed antibacterial effect against methicillin-resistant staphylococcus aureus bacteria. Taken together, the results suggest the equally substituted BG-5/5 (ie., the one consists of 5 mol% of both CuO and MgO) as a promising candidate for bone tissue engineering, among all newly designed BGs in this work, owing to its desirable cell proliferation, ALP activity, and antibacterial properties.