Direktbestimmung von Adrenalin und Noradrenalin im Urin durch Kopplung eines Hochdruck-Flüssigkeits-Chromatographen mit einem selektiven Fluorescenz-Reaktionsdetektor

High-performance liquid chromatographic determination of urinary free catecholamines with electrochemical detection after prepurification on immobilized boric acid

A reliable high-performance liquid chromatographic method is presented for the determination of the urinary free catecholamines noradrenaline, adrenaline and dopamine. Urine is purified on a column of immobilized boric acid. Catecholamines are separated by ion-pair reversed phase high-performance liquid chromatography and detected electrochemically. The method is suited for routine analysis. It allows the determination of urinary free catecholamines in concentrations as low as 1 microgram/1 for noradrenaline and adrenaline and 5 micrograms/1 for dopamine. A single analysis can be completed within 1 h. Routine analyses can be carried out in a series of 40 samples within 2 days. The within-assay and between-assay coefficients of variation of the analyses in urine were both 2.9% for noradrenaline, both 5.0% for adrenaline, and 1.9 and 2.1% for dopamine. The chromatographic properties of the immobilized boric acid were investigated. In particular, the elution pattern of a series of catecholamine metabolites and analogues was determined. Under the conditions used, only basic compounds containing both a vicinal hydroxyl configuration and a primary or secondary amino group adsorb and elute together with the free catecholamines.

Micro high-performance liquid chromatographic system with micro precolumn and dual electrochemical detector for direct injection analysis of catecholamines in body fluids

A new micro high-performance liquid chromatographic system has been developed, which determines catecholamines from directly injected human urine without any sample pretreatment. The system consists of a mixing junction for adjusting the sample to pH 8.5, a micro alumina precolumn for enriching catecholamines in the sample, and a dual electrochemical detector for selectively detecting catecholamines based on their electrochemical reversibility. The system is able to operate with directly injected body fluids and to determine simultaneously all of the four catecholamines with high precision.

Semi-automated fluorimetric method for the estimation of urinary catecholamines using high-performance liquid chromatography

A high-performance liquid chromatographic method for the quantitation of adrenaline and noradranaline in urine is described, using fluorescence detection. The effluent from the liquid chromatograph is led directly into an analyser to produce the fluorescent trihydroxy-indoles from the catecholamines. The method is more reliable and specific than conventional fluorescence techniques. Both catecholamines can be detected at levels of 0.5 ng on the column.