EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Mesoporous glass nanoparticles (MGNs) on the SiO2-P2O5-CaO system are receiving great research interest for bone regeneration applications. The good biological capabilities of MGNs can still be improved by doping with inorganic ions and loading with biologically active molecules. In this communication, two MGNs compositions: 79.5SiO2-2.5P2O5-18CaO (MGN-79.5) and 60SiO2-4P2O5-36CaO (MGN-60) were synthesized and doped with 2.5 or 4 mol-% of ZnO, because of the osteogenic and bactericidal properties of Zn2+ ions, and loaded with Curcumin as a bactericidal substance. The osteogenic and antibacterial capabilities of MGNs were evaluated in vitro. Transmission Electron Microscopy showed that both ZnO-containing and ZnO-free MGNs exhibited radial mesoporous and a diameter close to 100 nm. MGNs exhibited good properties for their intended biomedical applications including negative Z-potential (- 18 mV) at physiological pH, due to the presence of silanol groups on the surface, and very high BET surfaces, in the range of 700 ± 100 m2/g. On the other hand, MGNs were successfully internalized by MC3T3-E1 pre-osteoblastic cells that showed proliferation with time without significant differences for ZnO-containing samples. However, MGNs doped with 2.5% or 4% of ZnO exhibited lower cytotoxicity than Zn-free ones. Antibacterial assays showed a decrease in S. aureus population for MGNs doped with zinc and loaded with Curcumin. Thus, after 24 h, S. aureus proliferation decreased to 99% and 97% in Zn-MGN-60 and Zn-MGN-79.5 compared with control. Moreover, a synergistic effect was observed when ZnO and Curcumin were simultaneously present. Therefore, Zn-MGNs loaded with Curcumin exhibited higher osteogenic activity and enhanced the antibacterial effect against S. aureus. These results suggest that the system MGNs + ZnO + Curcumin is a promising candidate for bone regeneration therapies with capabilities to fight infection.