Electrochemical determination of norepinephrine by means of modified glassy carbon electrodes with carbon nanotubes and magnetic nanoparticles of cobalt ferrite

Abstract

This study describes the electrochemical preparation of the electrocatalytic oxidation/reduction of noradrenaline in modified glassy carbon of cobalt ferrite nanoparticles and carbon nanotubes (GC/MWCNT/FCo98). The cobalt ferrite powder was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The optimum conditions found in an electrode composition were 4 μL of cobalt ferrite and 10 μL of carbon nanotubes in 0.1 mol L−1 PBS at pH 7.0. The electrode displays electrochemical behavior in a wide potential range (−0.4 to 1.0 V vs. Ag/AgCl), high conductivity, and electrode stability/durability in 0.1 mol L−1 PBS. Catalytic oxidation of noradrenaline was performed at the unmodified GC electrode at +0.60 V vs. Ag/AgCl and current of 0.17 μA and modified GC with cobalt ferrite nanoparticles and carbon nanotubes at +0.54 V vs. Ag/AgCl and current of 0.23 mA. With regard to the anodic peak current (Ipa) versus noradrenaline concentration by means of the amperometric method at the modified electrode, (which is linear in the 0.16 and 1.91 mmol L−1 concentration range), the concentration limit was 0.76 μmol L−1. In this way, the modified electrode GC/MWCNT/FCo98 was found to be a promising application for the determination of this neurotransmitter in the area of neuroscience.