Hamzeh Pezhhan - Student of PhD in analytical chemistry (refinery Laboratory chemist
Mehdi Amani - MS in analytical chemistry (Laboratory Shift Supervisor

Multi walled carbon nanotube modified carbon-ceramic electrode (MWCNT/CCE) was employed for the simultaneous determination of dopamine (DA), ascorbic acid (AA), and uric acid (UA). TheMWCNT/CCE displayed excellent electrochemical catalytic activities. The oxidation over potentials ofDA, AA, and UA decrease significantly and their oxidation peak currents increase dramatically at MWCNT/CCE compared with bare CCE. Differential pulse voltammetry (DPV) was used for the simultaneous determination of DA, AA, and UA in their ternary mixture. The peak separations betweenAA and DA, and DA and UA are large up to 127 mV and 132 mV, respectively. The calibration curves for AA, DA, and UA were obtained in the range of 49.5-800 μM, 0.97-25 μM, and 0.97-54 μM, respectively. The detection limits (S/N = 3) were 15.71 μM, 0.41 μM, and 0.62 μM for AA, DA, UA and,respectively. The present method was applied to the determination of AA, DA, and UA in real environmental wastewaters sample (respect to UA) by using standard adding method and the results were satisfactory.

MWCNT, CCE, Dopamine, Ascorbic acid, Uric acid