Electrochemical performance of 8-hydroxy-2′-deoxyguanosine and its detection at poly(3-methylthiophene) modified glassy carbon electrode

Highly Sensitive Electrochemical Sensor for the Determination of 8-Hydroxy-2′-deoxyguanosine Incorporating SWCNTs-Nafion Composite Film

“…Figure 1 shows the cyclic voltammograms of 8-OHdG on bare GCE (curve (A)), MWCNTs/GCE (curve (B)), and SWCNTs/GCE (curve (C)). On bare GCE, the anodic peak potential of 8-OHdG appears at about +0.38 V. This is in agreement with the reports by Li et al [27] and Gutiérrez et al [30]. On MWCNTs/GCE and SWCNTs/GCE, the anodic peak potentials all positively shift from +0.38 V to +0.41 V. This suggests that MWCNTs and SWCNTs should not have an observed catalytic function for electrochemical oxidation of 8-OHdG.…”

“…Therefore, the electrochemical determination of 8-OHdG was examined using DPV at the fabricated .229 A/ M, respectively. The detection limit in this work (8.0 nM) is much lower than that reported using poly(3methylthiophene) modified GCE (0.10 M) [27] and MWC-NTs/PEI modified electrode (0.10 M) [30]. The slope of the linear range at low concentrations in this work is much higher than that reported using poly(3-methylthiophene) modified GCE (0.361 A/ M, Φ = 3mm) [27] and using MWC-NTs/PEI modified electrodes (2.67 A/ M, Φ = 3mm) [30].…”

“…Some efforts have been made to improve the sensitivity and selectivity of electrochemical sensors for quantifying 8-OHdG, mainly by modification of GCE using nanomaterials and polymers. In 2007, Li et al [27] reported an electrochemical sensor for quantifying 8-OHdG on a poly(3-methylthiophene) modified GCE with a detection limit of 0.10 M. Other work [28] they did in 2013 was on the electrochemical reduction synthesis of graphene/Nafion nanocomposite film and their results showed a high level of electrochemical performance on the oxidation of 8-OHdG. A wide linear range of 0.07-33.04 M and a low detection limit of 1.12 nM for 8-OHdG were obtained using linear sweep voltammetry.…”

Fabrication of the DNA/poly(3-methylthiophene) composite film modified electrode and its application for the study on the voltammetric behavior and determination of 8-hydroxy-2′-deoxyguanosine

“…It was reported that equivalent UA interferes with the electrochemical response of 8-OH-dG at bare GCE due to the preferred adsorption of UA onto the active electrode surface [42] . However, our previous studies show the interference of UA on 8-OH-dG can be reduced at the P3MT/GCE [21] . Herein, the interference of UA can be reduced more efficiently at the DNA/P3MT/GCE.…”

“…Besides, P3MT modified electrodes have been extensively reported and showed excellent electrocatalytic effect on many compounds. Our previous study reported the electrochemical performance and the detection of 8-OH-dG at the P3MT modified GCE [21] . However, the sensitivity and selectivity were not very satisfactory for the determination of 8-OH-dG in real samples.…”