"Titanium dioxide (TiO) is a semiconductor material that exhibits antibacterial activity due to its photocatalytic properties under ultraviolet light. On the other hand, silver also exhibits strong antibacterial activity towards a wide range of microorganisms and TiO with silver addition exhibits more efficient photocatalytic properties than unmodified TiO. In this work, TiO nanoparticles were synthesized by the hydrothermal method and modified with silver by two different methods: wet impregnation () and incorporation. The antimicrobial activity of TiO nanoparticles synthesized and modified by both methods was evaluated against and . The results showed that TiO nanoparticles have anatase phase. Also, spherical morphology with a mean particle size around 10.6 nm was obtained. The presence of silver in the modified TiO nanoparticles was confirmed by EDS and XPS. TiO particles modified by the method, showed a better bactericidal activity compared to the particles modified by incorporation method and TiO unmodified nanoparticles. This study demonstrated that both methods used to modify the titanium dioxide nanoparticles are effective as bactericidal materials and better results were found for the method."