title: Nanostructured composite material graphite/TiO2 and its antibacterial activity under visible light irradiation.
abstract: The paper addresses laboratory preparation, characterization and in vitro evaluation of antibacterial activity of graphite/TiO2 nanocomposites. Composites graphite/TiO2 with various ratio of TiO2 nanoparticles (30wt.%, and 50wt.%) to graphite were prepared using a thermal hydrolysis of titanylsulfate in the presence of graphite particles, and subsequently dried at 80°C. X-ray powder diffraction, transmission electron microscopy and Raman microspectroscopy served as phase-analytical methods distinguishing anatase and rutile phases in the prepared composites. Scanning and transmission electron microscopy techniques were used for characterization of morphology of the prepared samples. A developed modification of the standard microdilution test was used for in vitro evaluation of daylight induced antibacterial activity, using four common human pathogenic bacterial strains (Staphylococcus aureus, Escherichia coli, Enterococcus faecalis and Pseudomonas aeruginosa). Antibacterial activity of the graphite/TiO2 nanocomposites could be based mainly on photocatalytic reaction with subsequent potential interaction of reactive oxygen species with bacterial cells. During the antibacterial activity experiments, the graphite/TiO2 nanocomposites exhibited antibacterial activity, where differences in the onset of activity and activity against bacterial strains were observed. The highest antibacterial activity evaluated as minimum inhibitory concentration was observed against P. aeruginosa after 180min of irradiation.
authors.affiliation: Nanotechnology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic; Regional Materials Science and Technology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic. Electronic address: katerina.dedkova@vsb.cz.
authors.forename: Kateřina
authors.initials: K
authors.lastname: Dědková
authors.affiliation: Nanotechnology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic.
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Lang
authors.affiliation: Agel Laboratories a.s., Clinical Microbiology Laboratory, Zalužanského 1192/15, 703 84 Ostrava-Vítkovice, Czech Republic.
authors.forename: Kateřina
authors.initials: K
authors.lastname: Matějová
authors.affiliation: Nanotechnology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic.
authors.forename: Pavlína
authors.initials: P
authors.lastname: Peikertová
authors.affiliation: Department of Material Engineering, Faculty of Metallurgy and Materials Engineering, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Holešinský
authors.affiliation: Regional Materials Science and Technology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic; Department of Material Engineering, Faculty of Metallurgy and Materials Engineering, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic.
authors.forename: Vlastimil
authors.initials: V
authors.lastname: Vodárek
authors.affiliation: Nanotechnology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic; Regional Materials Science and Technology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava-Poruba, Czech Republic.
authors.forename: Jana
authors.initials: J
authors.lastname: Kukutschová
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000528:radiation effects; D006108:Graphite / Q000737:chemistry*; D006801:Humans; D008027:Light; D053758:Nanoparticles / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; C009495:titanium dioxide; D006108:Graphite; D014025:Titanium
keywords: Antibacterial activity; Raman microspectroscopy; Staphylococcus aureus; XRD