Immobilization and Hybridization of DNA/DNA of the rfbE Gene Escherichia Coli O157:H7 on Gold Electrode Surface for the Detection of Specific Sequences by Electrochemical Impedance Spectroscopy Method

Minaei, M E.; Saadati, M.; Najafi, M.; Honari, H.

Immobilization and Hybridization of DNA/DNA of the rfbE Gene Escherichia Coli O157:H7 on Gold Electrode Surface for the Detection of Specific Sequences by Electrochemical Impedance Spectroscopy Method

Authors

M E. Minaei

M. Saadati

M. Najafi

H. Honari

Abstract

In this paper, the immobilization and hybridization of single strand DNA (ssDNA) sequences of rfbE gene Escherichia coli O157:H7 has been studied by electrochemical impedance spectroscopy technique. A self-assembled monolayer of the ssDNA was immobilized on the gold electrode for three hours at ambient temperature (25C). A mixed monolayer comprising both mercaptohexanol (MCH) and mercaptopropionic acid (MPA) were used as an interface design for developing biosensor. The hybridization of DNA/DNA was performed by immersion the modified gold electrode with ssDNA at a concentration of target DNA, 1 μM in the phosphate buffer solution (pH 7.4). Cyclic voltammetry and electrochemical impedance spectroscopy techniques were used for investigation of the DNA immobilization and hybridization. Results showed that immobilization and hybridization of DNA on gold electrode is suitable. This research underlie the future development of nanobiosensor electrochemical for detection of biological agents.

Keywords

Hybridization DNA/DNA

Electrochemical Impedance Spectroscopy

Biosensor