Evaluation of a New Method for the Analysis of Free Catecholamines in Plasma Using Automated

was automated recently, but analysis of plasma samples posed special difficulties. The present study was under-taken to evaluate a new method for the automated analysis of plasma catecholamines. Methods: The procedure is based on an improved sample handling system that includes dialysis and sam-ple clean-up on a strong cation trace-enrichment car-tridge. The catecholamines norepinephrine, epineph-rine, and dopamine are then separated by reversed-phase ion-pair chromatography and quantified by electrochemical detection. Results: Use of a 740-mL sample is required to give the catecholamine detection limit of 0.05 nmol/L and ana-lytical imprecision (CV) between 1.1 % and 9.3%. The assay can be run unattended, although>12 h of analysi