Determination of amino acids on copper-based electrodes

In this Thesis, electrochemical behavior of the flow detector made of the thin copper wires was studied. This detector is suitable for the determination of amino acids without preliminary derivatization; in this case, tyrosine was used as the model compound. Suitable activation procedure for the copper electrode was found, which assured the stable baseline with lowest possible background current. It was also found that the optimum detection potential for tyrosine determination is 0.3 V. It was shown that the mass of the copper electrode does not influence the response of the electrode. Nevertheless, according to the comparison of the theoretical and found charge, the electrochemical reaction is not quantitative. Therefore, the electrode works in amperometric and not in coulometric mode. Finally, linearity of the current response in dependence on the tyrosine concentration was confirmed in the concentration range from 1.0·10-3 mol·dm-3 to 2.0·10-5 mol·dm-3 . Limit of detection was 1.5·10-5 mol·dm-3 and limit of quantification was 5.1 ·10-5 mol·dm-3