This research aims to study the antibacterial activity of thin films nanostructured TiO₂ doped with Ag and Cu on Gracilicutes and Firmicutes bacteria with clinical significance. The thin films were deposited on glass substrates without heating during the deposition by radio frequency magnetron co-sputtering of TiO₂ target and pieces of Ag and Cu. The total surface area of Ag was 60 mm² and this one of Cu was 100 mm². The r.f. power was 50W and sputtering atmosphere was Ar (0,8 Pa). The thickness of the films was about 60 nm. The experiment was conducted under day light regime. The test strains Bacillus cereus, Staphylococcus epidermidis, Salmonella enterica, Escherichia coli and Pseudomonas sp. were used. The bactericidal effect was established at different time point between 30 min - 90 min for Pseudomonas sp. and S. enterica. The Firmicutes bacteria B. cereus and S. epidermidis were killed at 4^th and 8^th h of the treatment respectively. The effect against E.coli was bacteriostatic till 10^th hour. The toxic effect was evaluated by classical Koch's method and optical density measurments. The results were confirmed by assessment of dehydrogenase activity inhibition. The film could be used in medical and clinical practice.

nanomedicine, bactericidal effect, Gram positive and Gram negative bacteria, clinical significant strains

Dragomira S. Stoyanova

World BioDiscovery Congress 2017