Electrochemical Detection of Selected Organic Components in the Eluate from High-Performance Liquid-Chromatography

Abstract

Abstract High-performance liquid chromatography can be combined with hydrodynamic thin-layer electrochemistry for determination of trace amounts of organic constituents in complex samples. With small and inexpensive analyzers based on these two techniques, as little as 1 pg of an electrochemically active component can be detected in a few minutes. Because many of the important low-molecular-weight organic constituents of body fluids— both endogenous metabolites and drugs—undergo electrochemical reactions, it seems reasonable to presume that useful assays might be developed by using the above methodology. Beginning to explore this presumption, we illustrate how uric acid, ascorbic acid, catecholamines, and related tyrosine metabolites might be measured in urine and serum. In some cases, liquid chromatography with electrochemical detection provides better sensitivity, selectivity, and speed than traditional methods, while minimizing the need for analytical reagents. We describe the basic approach and progress to date and suggest future applications.