Principle of electrolytic chromatography and coulopotentiography and its application to flow-injection analysis

Yoshida, Zenko; Kihara, Sorin*; Fujinaga, Taichiro*

A quantitative electrolysis of an electro-active species in a sample solution can be achieved very rapidly when the solution is allowed to flow through and be electrolyzed at a column electrode. Complete electrolysis of the species is attained with a small over-voltage, even if the electrode reaction is slow. The electrolytic method using the column electrode is suitable for automated or remote-controlled operation. Because of unmatched advantages, the column-electrode electrolysis method has been widely applied to the coulometric determination of species in a flowing sample solution and to liquid chromatography as a coulometric detector. This technique is especially favorable for elucidating mechanism of such complicated reactions as that involving unstable intermediates. In the present article, a principle and a feature of the column-electrode electrolysis are presented and the advantages of these methods are reviewed based on recent works on its application to flow-injection analysis and to a study of the redox reaction of actinide ions or the reaction of short-lived radicals.