A simple and sensitive electrochemical detection of furazolidone based on an Au nanoparticle functionalized graphene modified electrode

A new sensor using a glassy carbon electrode modified with graphene and Au nanoparticles (Gr/Au/GCE) was designed to investigate the electrochemical behavior of furazolidone (FZD). The morphology and nature of the modified electrode were characterized by UV-vis spectroscopy, transmission electron microscopy (TEM) and electrochemical impedance spectroscopy (EIS). FZD was reduced on the Gr/Au/GCE at lower potentials with a higher peak current, compared to the bare GCE, through an irreversible process. These results arose from the synergistic effect of the deposited Gr/Au suspension on the GCE. For this article, several parameters, such as pH, scan rate, and the amount of modifier had been studied. Under optimal conditions, amperometry (AMP) and differential pulse stripping voltammetry (DPSV) were applied to the determination of FZD. Linear dynamic ranges of 1- 674 mmol L-1, and 0.02- 0.14 mmol L-1 and 0.14-400 mmol L-1 with detection limits of 0.64 mmol L-1 and 0.0126 mmol L-1 were obtained using AMP and DPSV, respectively. The sensor was also successfully applied to the determination of FZD in real samples, obtaining satisfactory recoveries.