Antimicrobial properties of green synthesized novel TiO₂ nanoparticles using Iranian propolis extracts

The oral antimicrobial and cytotoxic properties of green synthesized novel titanium dioxide nanoparticles (TiO₂ NPs) using Iranian propolis extracts were investigated on oral bacteria and fibroblast cells. In this study, propolis was sampled, and alcoholic extracts were prepared. The TiO₂ NPs were biosynthesized using propolis extracts. The synthesized TiO₂ NPs were characterized by scanning electron microscope (SEM), X-ray diffraction analysis, energy-dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering, ultraviolet-visible (UV-Vis), transmission electron microscope, Brunauer-Emmett-Teller, and zeta potential. MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide), minimal inhibitory concentration, minimum bactericidal concentration, minimum fungicidal concentration, biofilm formation, and degradation tests were studied to clarify the oral antimicrobial properties of green synthesized TiO₂  NPs. According to the FTIR analysis, the propolis extract contained flavonoids and phenolic compounds in addition to TiO₂ NPs. Additionally, UV-Vis revealed that intense bands had formed NPs. EDX spectra and SEM images revealed that the stabilizing agent was in perfect quasi-spherical shapes around 21 nm. An EDX spectrum was used to verify the presence of titanium and oxygen. There were no significant cytotoxicity effects. The antibacterial results showed that Pro1TiO₂ (Khalkhal sample) had better effects than Pro2TiO₂ (Gilan sample) and TiO₂ NPs. The present study presents a new process for synthesizing TiO₂ NPs from propolis extracts with less toxic effects and user-friendly, eco-friendly, and economical materials. Pro1TiO₂ NPs may be considered the best candidate for clinical application.