Detection of Guanine and Adenine Using an Aminated Reduced Graphene Oxide Functional Membrane-Modified Glassy Carbon Electrode

Abstract

A new electrochemical sensor based on a Nafion, aminated reduced graphene oxide and chitosan functional membrane-modified glassy carbon electrode was proposed for the simultaneous detection of adenine and guanine. Fourier transform-infrared spectrometry (FTIR), transmission electron microscopy (TEM), and electrochemical methods were utilized for the additional characterization of the membrane materials. The prepared electrode was utilized for the detection of guanine (G) and adenine (A). The anodic peak currents to G and A were linear in the concentrations ranging from 0.1 to 120 μM and 0.2 to 110 μM, respectively. The detection limits were found to be 0.1 μM and 0.2 μM, respectively. Moreover, the modified electrode could also be used to determine G and A in calf thymus DNA.

Simultaneous Determination of Four DNA bases at Graphene Oxide/Multi-Walled Carbon Nanotube Nanocomposite-Modified Electrode

“…These experimental results matched with previous literature records [11,22,28,[31][32][33][34]. As shown in the reaction scheme (1)-(3) and (5) of Scheme 2, two protons and two electrons were postulated to be involved in rate determining steps of electrochemical oxidations of UA G, A, and C [11,22,31,32,34]. While for oxidation of T, only one electron and one proton were involved (reaction scheme (4), Scheme 2) [35].…”

“…All these values were close to the Nernstian theoretical value of 59.1 mV/pH which indicated that there was an equal number of protons and electrons exchanged for each analyte in the electrochemical oxidation mechanisms [31]. These experimental results matched with previous literature records [11,22,28,[31][32][33][34]. As shown in the reaction scheme (1)-(3) and (5) of Scheme 2, two protons and two electrons were postulated to be involved in rate determining steps of electrochemical oxidations of UA G, A, and C [11,22,31,32,34].…”

“…To the best of our knowledge, no study has been done to detect all four bases simultaneously in the presence of UA using nanocomposite modification of GCE. Both GO and MWCNT have been widely used nanomaterials for the modification of electrodes since they possess excellent mechanical flexibility, bio-compatibility, stability, large surface area, and high electrochemical conductivity [10,[22][23][24]. Recently, a novel class of hybrid materials has been introduced which are generated by hybridizing MWCNT with graphene or graphene oxide sheets [25].…”

“…Moreover, this hybrid is beneficial for sensor fabrication because the π-π stacking interaction between the hydrophobic region of GO and the walls of MWCNT assist in avoiding the restacking of the MWCNT and increase the stability of the GO-MWCNT dispersion [25,26]. Additionally, the natural polymer, CHT, is used as a dispersing material in the modification steps of GCE surfaces [22]. An ideal candidate for sensor fabrication is CHT due to its unique properties such high stability, biocompatibility, good adhesion and insolubility in water [27,28].…”

Graphene and Graphene-Based Nanomaterials for DNA Detection: A Review

“…This novel electrode system could overcome the existed drawbacks for most electrode materials, like the relative narrow potential window, high background current and slow electron transfer [ 111 , 112 ]. Then the aminated reduced graphene oxide functional membrane was used to modify the GCE and the device was successfully applied in the detection of guanine and adenine [ 113 ]. Figure 3 d illustrated the preparation processes of the electrode and the corresponding TEM image of each structure.…”