采用液相色谱-电喷雾串联质谱法对脑脊液中 5-甲基四氢叶酸进行定量分析。

Quantitation of 5-Methyltetrahydrofolate in Cerebrospinal Fluid Using Liquid Chromatography-Electrospray-Tandem Mass Spectrometry.

机构信息

Institute of Metabolic Disease, Baylor Scott & White Research Institute, Dallas, TX, USA.

出版信息

Methods Mol Biol. 2022;2546:311-319. doi: 10.1007/978-1-0716-2565-1_28.

Abstract

We describe a simple stable isotope dilution method for accurate and precise measurement of cerebrospinal fluid (CSF) 5-methyltetrahydrofolate (5-MTHF) as a clinical diagnostic test. 5-MTHF is the main biologically active form of folate and is involved in the regulation of homocysteine and numerous methylation reactions, including synthesis of neurotransmitters, lipids, DNA, and RNA. Measurement of 5-MTHF in CSF provides diagnostic information regarding disorders affecting folate metabolism within the central nervous system, in particular inborn errors of folate metabolism and cerebral folate deficiency. Determination of 5-MTHF in CSF (50 μL) was performed utilizing high-performance liquid chromatography coupled with electrospray positive ionization tandem mass spectrometry (HPLC-ESI-MS/MS). 5-MTHF in CSF is determined by a 1:2 dilution with internal standard (5-MTHF-C) and injected directly onto the HPLC-ESI-MS/MS system. Each assay is quantified using a five-point standard curve (25-400 nM) and has an analytical measurement range of 3-1000 nM.

摘要

我们描述了一种简单的稳定同位素稀释方法，用于准确、精密地测量脑脊液（CSF）中 5-甲基四氢叶酸（5-MTHF），作为一种临床诊断测试。5-MTHF 是叶酸的主要生物活性形式，参与同型半胱氨酸和许多甲基化反应的调节，包括神经递质、脂质、DNA 和 RNA 的合成。CSF 中 5-MTHF 的测量提供了关于影响中枢神经系统内叶酸代谢的疾病的诊断信息，特别是在叶酸代谢的先天性错误和大脑叶酸缺乏症中。使用高效液相色谱-电喷雾正离子串联质谱法（HPLC-ESI-MS/MS）对 CSF（50 μL）中的 5-MTHF 进行测定。通过与内标（5-MTHF-C）1:2 稀释，然后直接注入 HPLC-ESI-MS/MS 系统来确定 CSF 中的 5-MTHF。每个测定均使用五点标准曲线（25-400 nM）进行定量，分析测量范围为 3-1000 nM。