Analysis of oxysterols by electrospray tandem mass spectrometry
Analysis of oxysterols by electrospray tandem mass spectrometry
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DOI：
10.1016/j.jasms.2005.10.012
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发表时间：
2006-03-01
影响因子：
3.2
通讯作者：
Sjövall, J
中科院分区：
文献类型：
--
作者：
Griffiths, WJ;Wang, YQ;Sjövall, J
氧化甾醇是胆固醇的含氧衍生物。它们是胆固醇排泄途径的中间体，也可以被视为胆固醇的运输形式。在胆固醇骨架上引入额外的羟基有助于氧合甾醇通过血脑屏障，氧合甾醇参与了一系列胆固醇诱导的代谢效应。氧甾醇由于其结构中不含碱性或酸性官能团，难以用大气压电离质谱仪进行分析。在这篇通讯中，我们报告了一种氧化甾醇的衍生化和电喷雾质谱分析的方法。具有3β-羟基-Delta(5)结构的氧化甾醇被胆固醇氧化酶转化为3-oxo-Delta(4)类固醇，然后用Girard P试剂衍生化得到Girard P酰肼，然后用串联质谱仪进行分析。25-羟基胆固醇的氧化和衍生化分析的灵敏度提高了1000以上。
Oxysterols are oxygenated derivatives of cholesterol. They are intermediates in cholesterol excretion pathways and may also be regarded as transport forms of cholesterol. The introduction of additional hydroxyl groups to the cholesterol skeleton facilitates the flux of oxysterols across the blood brain barrier, and oxysterols have been implicated in mediating a number of cholesterol-induced metabolic effects. Oxysterols are difficult to analyze by atmospheric pressure ionization mass spectrometry on account of the absence of basic or acidic functional groups in their structures. In this communication, we report a method for the derivatization and analysis of oxysterols by electrospray mass spectrometry. Oxysterols with a 3 beta-hydroxy-Delta(5) structure were converted by cholesterol oxidase to 3-oxo-Delta(4) steroids and then derivatized with the Girard P reagent to give Girard P hydrazones, which were subsequently analyzed by tandem mass spectrometry. The improvement in sensitivity for the analysis of 25-hydroxycholesterol upon oxidation and derivatization was over 1000.