Electrochemical DNA Biosensor for the Detection of Interaction between Di[azino-di(5,6-azafluorene)-κ2-NN′] Dibromicoppers and DNA

A new Cu(II) complex CuL2Br2 (L = azino-di(5,6-azafluorene)-κ2-NN′) was synthesized, and a new method of electrochemical probe has been proposed for the determination of hepatitis B virus (HBV) based on its interaction with [CuL2]2+. This ligand, containing functional groups, as well as planar aromatic domains, is capable of binding to double-stranded DNA (dsDNA) more efficiently than to single-stranded DNA (ssDNA). Emphasis has been placed on the elucidation of the nature of the interaction by electrochemical techniques. The electroactive [CuL2]2+ could be employed as an electrochemical indicator to detect hybridization events in DNA biosensors. These biosensors have been constructed by immobilization of a probe DNA sequence from HBV onto glassy carbon electrode (GCE). After hybridization with the complementary target sequence, [CuL2]2+ was accumulated within the dsDNA layer. Electrochemical detection was performed by differential pulse voltammetry over the potential range. Using this approach, complemen...