RuO2 nanowires on electrospun CeO2-Au nanofibers/functionalized carbon nanotubes/graphite oxide nanocomposite modified screen-printed carbon electrode for simultaneous determination of serotonin, dopamine and ascorbic acid

Abstract

In this work, for the first time, a novel hybrid architecture of CeO2-Au nanofibers (CeO2-AuNFs) and single-crystalline RuO2 nanowires (RuO2NWs) have been synthesized by a combination of electrospinning and thermal annealing process. The CeO2-Au hybrid nanofibers were fabricated by the electrospinning technique and then annealed in air. The amorphous Ru(OH)3 precursors at relatively low temperature were efficiently converted into highly single-crystalline RuO2NWs on electrospun CeO2-AuNFs. Novel RuO2NWs–CeO2-AuNFs hybrid architecture in combination with graphite oxide (GO) and functionalized multiwalled carbon nanotubes (f-MWCNTs) further employed to modify screen printed carbon electrode (SPCE(in order to develop a sensitive electrochemical method with suitable properties for the simultaneous determination of serotonin (5-HT), dopamine (DA) and ascorbic acid (AA). Under the optimum operating conditions, linear calibration curves were obtained in the range of 0.01–150, 0.01–120 and 0.5–100 μM with a detection limit of 2.4, 2.8 and 160 nM for 5-HT, DA and AA, respectively. The proposed electrochemical sensor decreased the overpotentials as well as resolved the overlapping of the oxidation peak potentials. This sensor was successfully applied for the determination of 5-HT, DA and AA in biological fluids and pharmaceutical samples.