DEVELOPMENT OF ELECTROCHEMICAL FIA SYSTEM WITH IMMOBILIZED ENZYMES AS SPECIFIC POST-COLUMN DETECTOR OF HPLC

Abstract

A sensitive and highly selective method for the simultaneous determination of a variety of species is proposed. An amperometric flowinjection system with the immobilized enzyme reactors or enzyme sensors is used as the specific post detection system of HPLC, to convert compounds separated by a reversed-phase HPLC column to electroactive species (hydrogen peroxide and uric acid) which can be detected at 0.5 V vs. Ag/AgCl. The proposed system has been applied to the optically specific detection of L- and D-amino acids, the simultaneous detection of acetylcholine and choline, specific detection of a group of purine bases and purine nucleosides, and the high-sensitive detection of Llactate and pyruvate with substrate amplification. Specificity of the method is proposed by the HPLC column, the enzymatic reactions, and the electrochemical detector.