A Simplified HPLC-ECD Technique for Measurement of Urinary Free Catecholamines

Abstract

A simplified HPLC assay is described for quantification of free urinary catecholamines. The procedure involves exraction of catecholamines, (norepinephrine, epinephrine and dopamine) from urine, using columns filled with Biorex-70. The catecholamines from the extract were separated on a high performance liquid chromatographic system using reverse phase C18, 5 u column and determined by electrochemical detection. Integration and calculations are achieved by a data module using area ratio method with dihydroxybenzylamine as internal standard. Recovery of more than 90% was achieved for each catecholamine. A linear relationship between a wide range of concentrations and ratio of the area of amines to that of internal standard was observed. The method is simple and rapid and therefore can be used to analyze a large number of samples in one day and should prove useful in studies involving the role of catecholamines in different psychiatric disorders.