Magnetite graphene for electrochemical determination of uric acid

Abstract

In this work, the magnetite-reduced graphene oxide (Fe3O4/rGO) was fabricated for a selective voltammetric detection of uric acid. The magnetite-reduced graphene oxide is biocompatible sensing material that was synthesized through one-step reaction mechanism. The attachment of spherical like Fe3O4 particle on the rGO sheet was characterized by Fourier Transform Infrared (FTIR), Ultraviolet-Visible Spectroscopy (UV-Vis) and Scanning Electron Microscopy (SEM). The electrochemical performance of the Fe3O4/rGO/GCE electrode were studied by Cyclic Voltammetry (CV) and Differential Pulse Voltammetry (DPV). The superparamagtism property of the Fe3O4 anchoring on the rGO sheet provides a conduction pathway for the analyte diffusion meanwhile promote the electron transfer kinetic between the electroactive species and electrode surface. The enhanced current response signal produced from the reduction-oxidation process by the electroactive species were optimized further in parameters of scan rate, concentration of uric acid and pH value of the supporting electrolyte. The observed DPV response displays a linearity relationship on uric acid concentration ranging from 4 μM to 100 μM with correlation coefficient 0.989 and a sensitivity of 0.08478 μA/μM. The detection limit and limit of quantitation were found to be 3.04 μM and 10.14 μM respectively.