Electrocatalytic determination of epinephrine and uric acid using a novel hydroquinone modified carbon paste electrode

A sensitive and selective electrochemical method for the determination of epinephrine (EP) was developed using a modified carbon paste electrode (MCPE) with 2,2′-[3,6-dioxa-1,8-octanediylbis(nitriloethylidyne)]-bis-hydroquinone (DOH). Cyclic voltammetry was used to investigate the redox properties of this modified electrode at various solution pH values and at various scan rates. In differential pulse voltammetry, the modified electrode could separate the oxidation peak potentials of EP and uric acid (UA) present in the solution but at the unmodified CPE the peak potentials were indistinguishable. This method was also examined for determination of EP in EP injection.