DNA Hybridization Detection by Electrochemical Impedance Spectroscopy and Photoelectrochemistry

Abstract

Owing to the special properties of ssDNA and dsDNA molecules in their structures and electronic behaviors, they may give us many ideas for the fabrication of gene sensors and DNA-chips. In this work, photoelectrochemistry was first employed to characterize the behaviors of the self-assembled ssDNA probe modified electrode and the resultant dsDNA modified electrode. The obvious decrease in the photocurrent of the dsDNA modified electrode at open potential or a bias voltage indicated that photoelectrochemistry is another useful method for DNA hybridization detection. Concerning the special design of ssDNA probes, there is a further discussion on the relationship between the properties of DNA molecules and their photoelectric behaviors. In addition, the electrochemical impedance method was also employed to characterize and verify the hybridization event.