Electrochemical behavior of uric acid and epinephrine at an electrochemically activated glassy carbon electrode.

A pretreated glassy carbon electrode by electrochemical activation has been proposed for simultaneous investigation and determination of epinephrine and uric acid by differential pulse voltammetry. This pretreated glassy carbon electrode exhibits a potent and persistent electron-mediating behavior followed by well-separated oxidation peaks towards epinephrine and uric acid with a potential difference of 161 mV, which is large enough to determine epinephrine and uric acid individually and simultaneously. Under the optimum condition, the detection limit of epinephrine is 8.9 x 10(-8)mol L(-1) and that of uric acid is 1.6 x 10(-7)mol L(-1). The proposed method was successfully used for the determination of epinephrine and uric acid in real samples with satisfactory results.