Electrochemical DNA Sensors for Rapid Detection of DNA Damage Induced by Fenton Reaction

A DNA electrochemical sensor was prepared by assembling layer-by-layer films of poly dimethyl diallyl ammonium chloride and calf thymus double-stranded DNA (CT-dsDNA) on the surface of a glassy carbon electrode (GCE). The assembling DNA was characterized by electrochemical methods and atomic force microscope. Ru(bpy)(3)(2+) was used as electrochemical catalyst to detect the oxidative damage of DNA in the membrane. The effects of incubation time and concentration of Fenton reagent on the damage of DNA were studied. The result showed that it could cause damage greatly when incubated in Fenton reagent for 15 min. The detectable concentration of Fenton reagent was 5.0 x 10(-5) M FeSO4/2.0 x 10(-4) M H2O2. The electrochemical method possesses high-sensitivity for detecting the damage of DNA.