Electrochemical Sensors based on Fe@Fe2O3 nanowires, N-Doped ZnO and Au nanoparticles for quercetin determination

Abstract

In this study, we developed an electrochemical sensor for the determination of quercetin (QR) based on nitrogen-doped zinc oxide (N-ZnO) and iron/iron(III) oxide(Fe@Fe2O3) nanowires and gold nanoparticles (AuNPs). N-ZnO nanomaterial was decorated onto the indium tin oxide (ITO) surface by high-temperature catalytic oxidation while AuNPs and Fe@Fe2O3 were prepared using the hydrothermal method and were then coated on N-ZnO/ITO electrode by drop-casting method to form Fe@Fe2O3/AuNPs/N-ZnO/ITO electrode. The electrochemical oxidation of QR at the Fe@Fe2O3/AuNPs/N-ZnO/ITO electrode was studied by cyclic voltammetry. It was found that the oxidation current of QR was significantly enhanced at the Fe@Fe2O3/AuNPs/N-ZnO/ITO electrode. By taking advantage of high surface area and good electron transfer of the nanomaterials, as well as the electrochemical oxidation reaction of QR, an electrochemical method was developed for the detection of QR with a linear range from 10 to 1000 μM (R2=0.961) and the limit of detection of 0.059 mM. This work provides a new electrochemical method for the detection of QR with improved performance by constructing an advanced electrochemical sensing platform.