Synthesis and Investigation of Antibacterial Activity of Thin Films Based on TiO 2 -Ag and SiO 2 -Ag with Potential Applications in Medical Environment.

Multiple antibiotic resistance has now become a major obstacle to the treatment of infectious diseases. In this context, the application of nanotechnology in medicine is a promising alternative for the prevention of infections with multidrug-resistant germs. The use of silver as a powerful antibacterial agent has attracted much interest. TiO 2 and SiO 2 thin films enhanced with Ag particles have been developed with the aim of maintaining the transparency of the polymer films. Antibacterial activity was evaluated for a Gram-negative species- Escherichia coli -in concentrations of 10 5 and 10 4 CFU/mL in different conditions-activation by UV irradiation, single layer and double layer. Increased antibacterial efficacy of TiO 2 -deposited foil was found for the tests that had been exposed to UV activation. In the case of bilayer tests, the efficiency was higher compared to those in a single layer, as the contact surface between the films and the bacterial suspension increased. Films can be used as a potential method to limit bacterial growth on hospital surfaces, such as telephone screens and medical equipment, given their optimized characteristics and proven antibacterial efficacy.