Antioxidant sensors based on DNA-modified electrodes.
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.
Liu
Jifeng
J
Laboratoire d'Electrochimie Physique et Analytique, Ecole Polytechnique Fédérale de Lausanne, Switzerland.
Roussel
Christophe
C
Lagger
Grégoire
G
Tacchini
Philippe
P
Girault
Hubert H
HH
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
D000975:Antioxidants; D017382:Reactive Oxygen Species; D014867:Water; C009495:titanium dioxide; D004247:DNA; D014025:Titanium