title: Bactericidal activity of titanium dioxide ultraviolet-induced films.
abstract: TiO2 films are used as a self-sterilization surface due to their property to form reactive oxygen species (ROS) when irradiated with ultraviolet light. These ROS attack bacteria and kill them. We present a new way to enhance the bactericidal activity of TiO2-films: formation of nanopores on the surface by four-beam high-power laser irradiation. Such surfaces have significantly higher antibacterial activity as compared to conventional TiO2 surfaces after 15 and 60min of UV irradiation. Study of the bacterial cell morphology by atomic force microscopy after 60min irradiation showed that Staphylococcus aureus 956 and Escherichia coli 321-5 undergo significant morphological changes. S. aureus assume atypical elongated shapes after UV treatment alone and swollen forms with protrusions after UV treatment on TiO2 surface. E. coli exhibit oval or round forms after UV treatment alone, and round forms with small protrusions, and destroyed cells after incubation under UV on the TiO2 film.
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Tomsk State University, ave. Lenina 36, Tomsk 634050, Russian Federation. Electronic address: pleskova@mail.ru.
authors.forename: S N
authors.initials: SN
authors.lastname: Pleskova
authors.affiliation: Institute of applied biotechnology of Nizhny Novgorod, Yablonevaya Street 22, Nizhny Novgorod 603093, Russian Federation. Electronic address: golubmay@mail.ru.
authors.forename: I S
authors.initials: IS
authors.lastname: Golubeva
authors.affiliation: Institute of applied physics of the Russian Academy of Science, Ul'yanov Street, 46, Nizhny Novgorod 603950, Russian Federation. Electronic address: verevkin@appl.sci-nnov.ru.
authors.forename: Y K
authors.initials: YK
authors.lastname: Verevkin
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D004926:Escherichia coli / Q000254:growth & development*; D058608:Nanopores; D013211:Staphylococcus aureus / Q000254:growth & development*; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D000900:Anti-Bacterial Agents; C009495:titanium dioxide; D014025:Titanium
keywords: Atomic-force microscopy; Bacteria; Bactericidal activity; Nanopores; TiO(2) film