Electrochemical Sensing of Dopamine and Epinephrine Using Self-assembled Fe3O4 Magnetic Nanoparticles on a Pyridine-grafted Glassy Carbon Electrode

A magnetic nanomaterial based electrochemical sensor was developed by immobilizing Fe3O4 nanoparticles (ca. 12 nm d.) on a pyridine molecule grafted glassy carbon electrode (Py-GCE) for the selective and sensitive determination of two important neurotransmitters, dopamine (DA) and epinephrine (EP) at neutral pH. The synthesised Fe3O4 magnetic nanoparticleswere characterized by FTIR, UV-Vis, TEM, XRD and XPS methods, whereas thefabricated electrodeswere characterized by using SEM, ATR-FTIR, CV and EIS techniques. Differential pulse voltammetry was used for the determination of DA and EP in the linear range of 0.2 to 1.2 mu M with the detection limits (S/N=3) of 0.34 nM and 0.61 nM, respectively. The sensor electrode exhibited high stability, reproducibility, good selectivity in the presence of potential interfering agents viz. ascorbic acid, uric acid, citric acid, glucose, etc. Theproposed method was successfully applied for the simultaneous determination of DA and EP in human blood sample and the recovery result was excellent.