Electrochemically Reduced Graphene Oxide as Screen‐printed Electrode Modifier for Fenamiphos Determination

Abstract

In this study, electrochemically reduced graphene oxide (ERGO) was used for the preparation of a screen‐printed modified electrode and applied for the voltammetric determination of fenamiphos (FNP) in tomato samples. Graphene oxide (GO) used for sensor construction was prepared according to an improved Hummers method and characterized by XRD, TEM, and FTIR, which confirmed the nanomaterial obtention. The ERGO formation was carried out from the electrodeposition by cyclic voltammetry, at 50 mV s−1 in the potential range of 0.0 to −1.5 V, during 50 cycles. ERGO‐SPE was used in the evaluation of the voltammetric behavior of FNP. The ERGO‐SPE proposed presented excellent electrochemical performance towards FNP oxidation, promoting an enhance on the anodic peak current and a decrease of peak potential. Under optimized conditions, it was possible to construct an analytical curve, using square wave voltammetry, with a linear region of 0.25 to 25.0 μM, with calculated limits of detection and quantification of 0.067 and 0.22 μM. From this, it was possible to analyze FNP in fortified tomato samples at three concentration levels, which showed recoveries values varying between 82 and 102 %. The ERGO‐SPE device proved useful in determining FNP, where the effect of the electrodeposition of the GO promoted a significant increase in the employability of the printed electrode.

Carbon Nanomaterials-Based Screen-Printed Electrodes for Sensing Applications

“…The sensor’s high sensitivity to glyphosate, its reproducibility, and its stability make it a viable sensor for use in environmental monitoring. Gevaerd et al [ 29 ] deposited electrochemically reduced graphene oxide onto SPCE to construct a sensor for fenamiphos determination in tomato samples. The sensitivity to fenamiphos oxidation allowed for achieving a low limit of detection and a high-percentage recovery, even in real samples.…”

Label-free aptasensor for p24-HIV protein detection based on graphene quantum dots as an electrochemical signal amplifier

“…The SPEs were obtained from Professor Craig E. Banks laboratory at Manchester Metropolitan University, in which the working and counter electrodes are made of graphite conductive ink, an Ag|AgCl conductive ink was used for the pseudo-reference electrode construction, and the final set is supported on a polyester substrate with the electrodes and electrical contacts areas delimited by an insulating ink [ [18], [19], [20], [21]].…”

Electrochemical Detection of Epinephrine Based on a Screen‐printed Electrode Modified with NiO−ERGO Nanocomposite Film

“…1 mg of GO was well-dispersed in 0.1 M phosphate buffer solution (pH 7.4) using a sonicator to form a final suspension of 1 mgmL À 1 . Electrochemical reduction of GO from this suspension was performed on the surface of the screenprinted electrode (SPE) in the potential range of À 1.5 V to 0 V at a scan rate of 50 mVs À 1 [21]. After the reduction step, the prepared electrode (ERGO/SPE) was washed with ultrapure water and made ready for use.…”