Voltammetric and impedimetric DNA detection at single-use graphite electrodes modified with gold nanorods.

In this study, single-use pencil graphite electrodes (PGEs) were modified by gold nanorods (AuNRs) and then single stranded oligonucleotide probe molecules (ssODNs) were immobilized onto the surface of AuNRs modified PGE. The electrochemical characterizations using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques were firstly performed to present the successfull modification of AuNR onto PGE surface. Under the optimum experimental conditions based on enhanced sensor response, single stranded thiol linked DNA probe ssODNs was immobilized onto AuNR modified PGE and accordingly, a sequence-selective DNA hybridization related to Hepatitis B virus (HBV) DNA was performed at the surface of AuNR modified electrodes. The impedimetric sequence-selective HBV DNA hybridization was then explored in the case of complementary (target), or noncomplementary (NC) DNA sequences.