Electrochemical determination of serotonin in urine samples based on metal oxide nanoparticles/MWCNT on modiﬁed glassy carbon electrode
journal of Sensing and Bio-Sensing Research, vol. 13, 17-27P.
The electrochemical response of serotonin on the modiﬁed electrode based on multiwalled-carbon-nanotube (MWCNT) doped respectively with nickel, zinc and iron oxide nanoparticles coating on glassy carbon electrode (GCE) at physiological pH 7 was determined using cyclic voltammetry (CV) and square wave voltammetry (SWV). The modiﬁed GCE/MWCNT-metal oxide electrodes exhibited excellent electrocatalytic activity towards the detection of serotonin at large peak current and lower oxidation potentials compared to other electrodes in- vestigated. The dynamic range for the serotonin determinationwas between 5.98 × 10 −3 μM to 62.8 μMwithde- tection limits 118, 129 and 166 nM for GCE/MWCNT-NiO, GCE/MWCNT-ZnO and GCE/MWCNT-Fe 3 O 4 sensors respectively. GCE-MWCNT-NiO was the bestelectrode in terms of serotonin currentresponse, electrode stability, resistance to fouling and limit of detection towards the analyte.The developed sensors were found to be electro- chemicallystable, reusable, economically effective due to theirextremely low operational cost, and have demon- strated good limit of detection, sensitivity and selectivity towards serotonin determination in urine samples. © 2017 Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/).