title: Antioxidant sensors based on DNA-modified electrodes.
abstract: TiO2/ITO modified electrodes were developed to quantitatively photooxidize adsorbed ds-DNA and to study the effect of antioxidants as ds-DNA protecting agents. TiO2 films are used for efficient ds-DNA immobilization, for ds-DNA oxidation through photogenerated hydroxyl radicals, and as electrodes for amperometric sensing. The films, prepared by a sol-gel process, are deposited on ITO glass electrodes. Damages occurring after ds-DNA oxidation by ROS are detected by adding MB as an intercalant probe and by monitoring the electrochemical reduction current of the intercalated redox probe. The MB electrochemical signal is found to be sensitive enough to monitor ds-DNA structure changes, and the electrochemical sensor has been applied to the evaluation of the antioxidant properties of glutathione and gallic acid.
authors.affiliation: Laboratoire d'Electrochimie Physique et Analytique, Ecole Polytechnique Fédérale de Lausanne, Switzerland.
authors.forename: Jifeng
authors.initials: J
authors.lastname: Liu
authors.forename: Christophe
authors.initials: C
authors.lastname: Roussel
authors.forename: Grégoire
authors.initials: G
authors.lastname: Lagger
authors.forename: Philippe
authors.initials: P
authors.lastname: Tacchini
authors.forename: Hubert H
authors.initials: HH
authors.lastname: Girault
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D015374:Biosensing Techniques / Q000379:methods*; D002384:Catalysis; D004247:DNA / Q000737:chemistry*; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010777:Photochemistry; D017382:Reactive Oxygen Species / Q000737:chemistry; D014025:Titanium / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D000975:Antioxidants; D017382:Reactive Oxygen Species; D014867:Water; C009495:titanium dioxide; D004247:DNA; D014025:Titanium