VOLTAMMETRIC DETERMINATION OF DOPAMINE WITH CARBON BLACK MICRO ELECTRODE

The electrochemical behaviors of dopamine (DA) at the carbon black micro-electrode was studied.It was shown by the experimental results that in a phosphate buffer medium of pH 4.5 (pH 3.8-5.2),linear relationship between the peak current and the concentration of DA in the range of 6.0×10-6-2.0×10-5mol·L-1 was obtained,with a detection limit (3σ) of 1.0×10-6mol·L-1 of DA.The proposed method has been applied to the determination of DA in samples of dopamine injection,giving values of RSD (n=5) less than 2.4% and recoveries in the range of 96%-102%.The results obtained by this method were found to be in conformity with those obtained by iodometry.