生物胺和氨基酸在代表神经传递的途径中被广泛表征。尽管已使用几种分析方法来检测相关流体(例如脑脊液(CSF))中的特定目标分子,但必须使用多种测定方法来调查所涉及的主要途径。本文介绍了一种GC / MS / MS方法的开发,该方法能够从单个50微升CSF样品中分析多达43种分析物(代表20个氨基酸和七个以上的神经化学途径)。在此程序中,首先将CSF样品用乙腈处理以沉淀蛋白质。然后将干燥的样品用2,2,3,3,3-五氟-1-丙醇和五氟丙酸乙酸酐的混合物衍生化,以用含氟基团取代所有活性氢原子。由于氨基酸和神经递质之间的浓度差异,在同一衍生提取物的单独进样中分析了这两种化合物。每次注射的总运行时间约为15-20分钟。该方法的基本特征是使用氩气作为电子捕获化学电离(ECCI)的反应气,因为使用更传统的气体(甲烷)缺乏足够的耐久性,无法考虑与本仪器一起使用。本文介绍了这种方法的发展,包括对所用化学电离
Further studies on a site-specific hydrogen transfer observed in electron capture negative ion chemical ionization mass spectrometry of hydroxyamine pentafluoropropionate derivatives
作者:G. K.-C. Low、A. M. Duffield
DOI:10.1002/oms.1210201002
日期:1985.10
AbstractFurther studies have demonstrated that the site‐specific hydrogen transfer process involved in the formation of the m/z 145 anion of β‐hydroxyamine pentafluoropropionate (PFP) derivatives observed under electron capture negative ion chemical ionization conditions occurs when the two functional groups are separated by up to five carbon atoms. Deuterium labelling has established that the site specificity, transfer of a hydrogen atom from the carbon adjacent to nitrogen to the OPFP group, is maintained in 4‐amino‐butan‐1‐ol‐N, O‐(PFP)2. The corresponding PFP derivatives of the N‐methylaminoalkanol‐(PFP)2 derivatives lack the m/z 145 species with m/z 163, [OPFP]− being the base anion. Substitution of alkyl groups on the carbon adjacent to oxygen results in a diminution of the ion intensity at m/z 145. with a marked increase in the intensity of m/z 144. The formation of the m/z 145 and 144 anions to proposed to proceed through the intervention of a fluoride ion‐molecule complex as outlined in Scheme 1 with the product ion distribution dependent on which of the two pathways is preferred.
Quantitative measurement of octopamines and synephrines in urine using capillary column gas chromatography negative ion chemical ionization mass spectrometry
作者:Kamal E. Ibrahim、Margaret W. Couch、Clyde M. Williams、Mary Beth. Budd、Richard A. Yost、John M. Midgley