Electrochemical flow-through system with DNA biosensor for biomedical and food technology applications

We present an electrochemical DNA-based biosensor arranged in a commercial flow-through cell. The DNA biosensor consists of a layer of double stranded calf thymus DNA deposited on the surface of a screen-printed carbon electrode without and with an interface formed by carbon nanotubes. Voltammetric and impedimetric characteristics of the biosensor were obtained and DNA interactions of medical and food interests were detected by using cyclic voltammetry peak current and potential signals of the [Fe(CN)₆]^3-/4- complex utilized as a redox indicator in the solution. Electrochemical impedance spectroscopy was used for the verification of the results. Finally, the biosensor was used for the detection of evaluation of DNA damage introduced by the Fenton reaction agents and antioxidative effects of standard chemicals and tea extracts.