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An improved technique for extracting catecholamines from body fluids.

I A Macdonald·D M Lake
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Abstract

This paper describes a technique for selectively extracting catecholamines from body fluids prior to quantification by high-performance liquid chromatography with electrochemical detection. The technique is a two-stage process, the first stage involves the extraction of cations from the sample whilst the second stage is a liquid-liquid extraction involving the complexation of the cationic catecholamines with diphenylborate. This technique provides a very specific extraction procedure which results in chromatograms with no interfering compounds, and gives absolute recoveries of 70-80% for noradrenaline (NA), adrenaline (A) and dihydroxybenzylamine (internal standard), with similar relative recoveries of the 3 compounds. The intra-assay coefficients of variation for the measurement of catecholamines in venous plasma taken from resting subjects, are 8-9% for both NA and A, whilst the inter-assay values are 8% for NA and 20% for A.

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Aluminum OxideBody FluidsCatecholaminesChromatography, LiquidEpinephrineHumansNorepinephrineComparative StudyJournal Article

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I A Macdonald, D M Lake. 1985. An improved technique for extracting catecholamines from body fluids.. https://doi.org/10.1016/0165-0270(85)90072-x

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