Electrochemical Determination of Dopamine in Serum in Presence of Uric Acid and Ascorbic Acid at a Sonogel-Carbon L-cysteine Modified Electrode

The objective of this work is to provide a tool for the electrochemical detection and quantification of dopamine in biological environments in the presence of ascorbic and uric acids (AA, UA). Sonogel electrodes modified with L-Cysteine prepared in this work showed very remarkable electrochemical performance for the determination of dopamine; the results obtained show good selectivity and sensitivity for dopamine, ascorbic acid and uric acid in serum. The influence of several parameters on selectivity and sensitivity were studied and optimized. The response of catalytic current with dopamine concentration shows a linear relation in the range from 10μM to 100μM with a correlation coefficient of 0, 9927 and a detection limit of 10−7 M. The applicability of the modified electrode for the analysis of biological fluid samples (serum) has been also demonstrated.