Electrode modification using reduced graphene oxide nanocomposites for diclofenac detection

Abstract

The electrochemical sensors based on graphene nanocomposite modified electrode for electrochemical detection (e.g. sulfite, diclofenac) were fabricated. This study is divided into two main parts. The first part is development of electrochemical sensor for sulfite detection. The modified electrode based on graphene showed the higher sensitivity than an unmodified electrode. howerver, the second part used reduced graphene oxide/platinum nanoparticles (RGO/PtNPs) modified electrode for the determination of diclofenac. The surface morphology of the modified electrode was characterized by using scanning electron microscopy (SEM). The cyclic voltammetry (CV) was employed to investigate the electrochemical performances of electrodes. All the factors affecting the sensitivity of this system were systematically evaluated. Under the optimized conditions, the modified electrode showed a higher current response signal compared to an unmodified electrode indicating the high sensitivity of this sensor. Moreover, the modified electrode provided a low limit of detection of 0.04 µM with a wide linearity of 0.1-100 µM. Eventually, this system was successfully applied for the determination of diclofenac in urine samples and the satisfactory results were obtained.