title: In vitro bactericidal and TEM study of the interaction of Ag-modified titania with coliform bacteria.
abstract: This research aimed to investigate in vitro photocatalytic bactericidal effect of Ag-TiO2 nanocomposite using Escherichia coli as a model organism. Highly dispersed, Ag-TiO2 nanocomposite is used with an average particle size of less than 20 nm. Bactericidal analysis was carried out in Luria Bertani medium on solid agar plates with various illumination time and different concentrations of Ag-TiO2 nanocomposite. Transmission electron microscopic analysis of bacterial section was used to detect the effect of irradiation of Ag-TiO2 nanocomposite on the ultra structure of the bacterial cell in order to reveal possible cellular damage. The mechanism underlying the action of photoexcited Ag-TiO2 nanocomposite on E. coli cell membrane is also evaluated. The results confirmed that E. coli cells after the contact with Ag-TiO2 nanocomposite were damaged since they showed membrane disorganization. This causes the enhanced level of membrane permeability leading to the build-up of Ag-TiO2 nanocomposite in the bacterial membrane and also cellular internalization of these nanoparticles.
authors.affiliation: a University of Cambridge , Cambridge , UK.
authors.forename: Ishrat
authors.initials: I
authors.lastname: Bano
authors.forename: R Vasant
authors.initials: RV
authors.lastname: Kumar
authors.forename: Abdul
authors.initials: A
authors.lastname: Hameed
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002384:Catalysis; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000187:drug effects*; D046529:Microscopy, Electron, Transmission; D053761:Nanocomposites / Q000032:analysis*; D010782:Photolysis; D012834:Silver / Q000737:chemistry / Q000494:pharmacology*; D014025:Titanium / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; C009495:titanium dioxide; D012834:Silver; D014025:Titanium