A Dual Screen-Printed Electrode with Palladium Nanoparticles for the Flow-Injection Amperometric Determination of Dopamine and Adrenaline

Abstract

© 2020, Pleiades Publishing, Ltd. Abstract: We proposed a method for the selective and highly sensitive amperometric determination of dopamine and adrenaline in the presence of ascorbic and uric acids in a flow-injection system. Screen-printed electrodes modified with palladium nanoparticles, exhibiting catalytic activity in the electrooxidation of catecholamines, were used as a detector. The difference between the oxidation peak potentials of these compounds is 200 mV. A linear bilogarithmic dependence of the analytical signal on the concentration of dopamine and adrenaline is observed in the ranges from 5 × 10–12 to 5 × 10–8 M and from 1 × 10–9 to 1 × 10–5 M, respectively. For simultaneous two-component analysis, screen-printed electrodes with two working electrodes were used, that is, dual screen-printed electrodes modified with palladium nanoparticles, which enable two substances to be determined simultaneously at two different potentials. The proposed method for the joint flow-injection amperometric determination of dopamine and adrenaline using a modified dual screen-printed electrode was tested in the analysis of urine.