Simultaneous determination of adrenaline, uric acid, and cysteine using bifunctional electrocatalyst of ruthenium oxide nanoparticles

In this study, ruthenium oxide nanoparticles were electrochemically deposited on the surface of a glassy carbon electrode (RuON-GCE). Electrochemical studies indicate that a modified electrode (RuON-GCE) plays the role of an excellent bifunctional electrocatalyst for the oxidation of adrenaline (AD) and uric acid (UA) in two different potentials. The charge transfer coefficient (α) and the heterogeneous charge transfer rate constant (k′) between the analytes and the electrodeposited nanoparticles were determined using cyclic voltammetry experiments. Through a different pulse voltammetric (DPV) method, the plot of the electrocatalytic current versus AD and UA concentrations emerged to be constituted of two linear segments with different sensitivities. Furthermore, the detection limits of AD and UA were estimated. In DPV, RuON-GCE could separate the oxidation peak potentials of AD, UA, and cysteine (Cys) present in the same solution though, at the bare GCE, the peak potentials were indistinguishable. Finally, the modified electrode activity was studied for the electrocatalytic determination of AD in an injection solution and UA in a human urine sample. The results were found satisfactory.