title: Antibacterial activity of kaolinite/nanoTiO2 composites in relation to irradiation time.
abstract: The paper addresses laboratory preparation and antibacterial activity testing of kaolinite/nanoTiO2 composite in respect of the daylight irradiation time. Kaolinite/nanoTiO2 composites with 20 and 40 wt% of TiO2 were laboratory prepared, dried at 105 °C and calcined at 600 °C. The calcination caused transformation of kaolinite to metakaolinite and origination of the metakaolinite/nanoTiO2 composite. X-ray powder diffraction, Raman and FTIR spectroscopic methods revealed titanium dioxide only in the form of anatase in all evaluated samples (non-calcined and calcined) and also transformation of kaolinite to metakaolinite after the calcination treatment. Scanning electron microscopy was used as a method for characterization of morphology and elemental composition of the studied samples. A standard microdilution test was used to determine the antibacterial activity using four human pathogenic bacterial strains (Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa). A lamp with a wide spectrum bulb simulating daylight was used for induction of photocatalysis. The antibacterial assays found all the KATI samples to have antibacterial potency with different onset of the activity when calcined samples exhibited antibacterial activity earlier than the non-calcined. Significant difference in antibacterial activity of KATI samples for different bacterial strains was not observed.
authors.affiliation: Nanotechnology 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: Institute of Public Health Ostrava, Partyzánské nám. 7, 702 00 Ostrava, 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: Jaroslav
authors.initials: J
authors.lastname: Lang
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: Nanotechnology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava, Poruba, Czech Republic.
authors.forename: Kateřina Mamulová
authors.initials: KM
authors.lastname: Kutláková
authors.affiliation: Nanotechnology Centre, VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava, Poruba, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Neuwirthová
authors.affiliation: Faculty of Mechanical Engineering VŠB - Technical University of Ostrava, 17. listopadu 15, 708 33 Ostrava, Poruba, Czech Republic.
authors.forename: Karel
authors.initials: K
authors.lastname: Frydrýšek
authors.affiliation: Nanotechnology 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* / Q000528:radiation effects*; D001419:Bacteria / Q000187:drug effects; D002384:Catalysis / Q000528:radiation effects; D007616:Kaolin / Q000737:chemistry* / Q000528:radiation effects; D008027:Light; D053761:Nanocomposites / Q000737:chemistry* / Q000528:radiation effects; D053758:Nanoparticles / Q000737:chemistry / Q000528:radiation effects; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects
chemical_list: D000900:Anti-Bacterial Agents; C009495:titanium dioxide; D007616:Kaolin; D014025:Titanium
keywords: Antibacterial activity; FTIR; Kaolinite/TiO(2) composites; Raman spectroscopy; Staphylococcus aureus; XRD