NOVEL DNA SENSOR FOR ELECTROCHEMICAL GENE DETECTION

Some commercially available intercalators have been found to be electrochemically active through voltammetric experiments. For example, daunomycin was oxidized at a low potential (446 mV) with a high current density (6.5 mu A/cm(2) in a 10 mu M solution) on a basal plane pyrolytic graphite electrode with an adsorbed DNA probe. Daunomycin was able to electrochemically distinguish between double and single stranded DNAs using linear sweep voltammetry. After the hybridization reaction of a model targeted gene with DNA probes adsorbed on the electrode, the electrochemical signal of daunomycin intercalated between base pairs of the formed hybrids on the electrode was measured. The use of daunomycin resulted in the detection of the targeted gene of 10(-8) g/ml in the buffer solution.