5-Amino-2-mercapto-1,3,4-thidiazole modified single-use sensors for electrochemical DNA analysis

In this study, single-use graphite electrodes modified with 5-amino-2-mercapto-1,3,4-thidiazole (AMT) were fabricated for electrochemical monitoring of DNA. The surfaces of AMT modified pencil graphite electrodes (PGEs) were characterized by scanning electron microscopy (SEM). Electrochemical behaviors of these electrodes were investigated using differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The effects of pretreatment of PGE and immobilization time and concentration of AMT were studied to facilitate an effective immobilization on PGE surface. The efficiency of immobilization is verified by measuring the oxidation signals of either AMT itself or adenine base of DNA, immobilized onto AMT modified electrodes.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► 5-Amino-2-mercapto-1,3,4-thidiazole (AMT) was used as the advanced modification material for disposable graphite sensor for DNA detection. ► The surface and electrochemical characterization of these sensors (AMT-PGEs) were performed by scanning electron microscopy and electrochemical impedance spectroscopy. ► AMT-PGEs provide a more suitable and stable surface for binding of DNA resulting with 2.5 folds increase at adenine signal comparison to the ones of unmodifed PGEs.