Abstract
The polarographic determination of amino acids as copper complex has alreadybeen introduced by Jones, Martin and others : This method is based on the factthat soluble copper-amino acid complex is formed by the addition of the copper phos phate suspension into amino acid solution. However, considerable errors are en countered in this method. The reason for this may be attributed to a relatively high solubility of copper phosphate and for lack of reproducibility, because they utilize such reaction as between liquid and solid. Such reaction process as mentioned above, there fore, should be avoided in order to reduce the errors. By thorough investigation the authors found a superior method which is employed a liquid-liquid reactoin. This method is used the solution of copper instead of the copper phosphate suspension, and then the pH of the solution is adjusted to 9.0, the precipitate is filtered off and the concentration of copper ion in the filtrate is determined polarographically.
