DNA electrochemical biosensor for the detection of short DNA sequences related to the hepatitis B virus

Nucleic acid hybridization forms the basis for the diagnosis of genetic and infectious diseases. Electrochemical biosensors, coupling the inherent specificity of DNA recognition reactions with the high sensitivity of physical transducers, thus hold great promise for sequence-specific detection. An electrochemical biosensor for the voltammetric detection of DNA sequences related to the hepatitis B virus (HBV) is described. Synthetic single-stranded oligonucleotides ("probe") have been immobilized onto carbon paste electrodes with the adsorption at a controlled potential. The probes were hybridized with different concentrations of complementary ('target') sequences. The formed hybrids on the electrode surface were evaluated by differential pulse voltammetry using cobalt phenanthroline, [Co(phen)(3)(3+)] as the indicator of hybridization reaction.