Smedes F, Kraak J C, Poppe H
J Chromatogr. 1982 Aug 13;231(1):25-39. doi: 10.1016/s0378-4347(00)80506-x.
A very simple solvent extraction system for the selective and quantitative isolation of adrenaline, noradrenaline and dopamine from plasma and urine is described. The extraction system makes use of the complex formation, in alkaline medium, between diphenylborate and the diol group in the catecholamines in combination with ion-pair formation. The influence of various parameters on the distribution coefficient was investigated by analysis of the liquid phases by high-performance liquid chromatography with electro-chemical detection. From these results the optimal extraction conditions can be selected. With hexane + 1% n-octanol containing 0.25% (w/v) of tetraoctylammonium bromide as extraction solvent, the catecholamines can be quantitatively isolated from plasma and urine at pH 8.6 in the presence of 0.1% (w/v) of diphenylborate. For urine the recovery was 101.5 + 1.9% for adrenaline, 100.6 +/- 2.0% for noradrenaline and 99.9 +/- 1.5% for dopamine. For plasma the recoveries were, respectively, 101.8 +/- 3.3%, 100.5 +/- 2.6% and 92.9 +/- 3.5%. The recovery of dihydroxybenzylamine, included in the study as internal standard, was determined to be 96.3 +/- 1.6% for urine and 89.9 +/- 2.7% for plasma. The applicability of the developed extraction system as clean-up and concentration step for the analysis of catecholamines in plasma and urine by high-performance liquid chromatography with electrochemical detection is demonstrated.
本文描述了一种非常简单的溶剂萃取系统，用于从血浆和尿液中选择性定量分离肾上腺素、去甲肾上腺素和多巴胺。该萃取系统利用了在碱性介质中，二苯硼酸盐与儿茶酚胺中的二醇基团形成络合物，并结合离子对形成的原理。通过高效液相色谱-电化学检测对液相进行分析，研究了各种参数对分配系数的影响。根据这些结果可以选择最佳萃取条件。以含有0.25%（w/v）溴化四辛铵的己烷+1%正辛醇作为萃取溶剂，在pH 8.6、存在0.1%（w/v）二苯硼酸盐的条件下，儿茶酚胺可从血浆和尿液中定量分离出来。对于尿液，肾上腺素的回收率为101.5±1.9%，去甲肾上腺素为100.6±2.0%，多巴胺为99.9±1.5%。对于血浆，回收率分别为101.8±3.3%、100.5±2.6%和92.9±3.5%。作为内标物纳入研究的二羟基苄胺，尿液中的回收率为96.3±1.6%，血浆中的回收率为89.9±2.7%。本文证明了所开发的萃取系统作为高效液相色谱-电化学检测分析血浆和尿液中儿茶酚胺的净化和浓缩步骤的适用性。
