Synthesis and photocatalytic effects of TiO2-Ag on antibiotic-resistant bacteria

Titanium dioxide (TiO2) is a semiconductor metal oxide extensively studied due to its photocatalytic properties that can be applied in various areas. However, the catalytic performance of TiO2 is limited at the UV spectrum, and the silver doping to titanium dioxide (Ag-TiO2) can increase the catalytic performance for visible light. In this work, Ag-doped TiO2 nanoparticles were synthesized to evaluate photocatalytic activity against sensitive and methicillin-resistant Staphylococcus aureus frequently associated with skin infections. The sol-gel method followed by Ag doping was applied to NPs synthesis. NPs were characterized by UV-vis spectroscopy, scanning electron microscopy (SEM), UV-vis diffuse reflectance spectrophotometry (DRS), Semi-quantitative energy dispersive spectroscopy (EDS) and Fourier transform infrared (FTIR) spectroscopy. FTIR and EDS results confirmed the doping of silver in TiO2. MEV analysis evidenced spherical nanoparticles between 8.5 - 25.6 nm. The TiO2 nanoparticles combined with silver improved the antimicrobial effect of TiO2 under visible light at 180 min, however, the greatest antimicrobial effect was observed under UV light at 120 min.