Electrochemical detection of serotonin in banana at green mediated PPy/Fe3O4NPs nanocomposites modified electrodes
Gloria Ebube Uwaya, Omolola E. Fayemi
Abstract
This study reports electrochemical detection of serotonin at a screen-printed carbon electrode (SPCE) modified with polypyrrole (PPy), doped with green iron (III) oxide nanoparticles. The synthesized iron (III) oxide nanoparticles is from Callistemon viminalis leaves (Fe3O4NPsL) and flowers (Fe3O4NPsF) extract. Modified SPCE-PPy-Fe3O4NPsL and SPCE-PPy-Fe3O4NPsF electrodes demonstrated good electrocatalytic activity towards serotonin detection compared to other electrodes studied at high anodic peak current. Fe3O4NPsL and Fe3O4NPsF represent iron (III) oxide nanoparticles synthesized from Callistemon viminalis leaves, and flowers extract respectively. The dynamic range for serotonin detection was from 0.007 to 0.1 μM with 0.021 and 0.020 μM detection limit (LoD) for SPCE-PPy-Fe3O4NPsL and SPCE-PPy-Fe3O4NPsF electrodes respectively. LoD values revealed SPCE-PPy-Fe3O4NPsF as best electrode while SPCE-PPy-Fe3O4NPsL had optimal current response towards serotonin and best electrode in terms of stability and simultaneous detection of 100 mM ascorbic acid (AA) and 0.1 mM serotonin (5-HT). In this study, SPCE-PPy-Fe3O4NPsL and SPCE-PPy-Fe3O4NPsF have proved promising for assay of serotonin in fruit sample (banana).