Multifunctional and Highly Sensitive Precolumn Reagents for Amino Acids in Liquid Chromatography/Tandem Mass Spectrometry
作者:Kazutaka Shimbo、Akihisa Yahashi、Kazuo Hirayama、Masakazu Nakazawa、Hiroshi Miyano
DOI:10.1021/ac900470w
日期:2009.7.1
We have developed novel precolumn derivatization reagent, p-N,N,N-trimethylammonioanilyl N′-hydroxysuccinimidyl carbamate iodide (TAHS), for sensitive analyses of amino acids using high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS). TAHS, an activated carbamate, was reacted briefly with the amino group to form a ureide bond under mild condition. The derivatives provided selective cleavage at the binding site between the reagent and the amino acid in the collision cell of the mass spectrometer and produced a characteristic fragment derived from the reagent moiety. Using the precursor ion scan mode of the tandem mass spectrometry, amino acids derivatized with the reagents were simultaneously measured on the chromatogram. Selective cleavage also enabled the straightforward isotope ratio analysis of amino acids by the selected reaction monitoring mode, which was applicable in 13C metabolic flux analysis. TAHS, which contains a cationic quaternary amine, achieved subfemtomole to attomole levels of amino acids detection by measurement in the selected reaction monitoring mode. We also synthesized trideuteriummethyl-substituted TAHS, TAHS-d3, and demonstrated that the combination of TAHS and TAHS-d3 is useful in comparing amino acid concentrations between two different samples using a single LC/MS/MS measurement.
我们开发了新型柱前衍生试剂,p-N,N,N-三甲基氨基苯胺基 N'-羟基琥珀酰亚胺基氨基甲酸酯碘化物 (TAHS),用于使用高效液相色谱/电喷雾电离串联质谱 (LC/ESI-MS/多发性硬化症)。 TAHS是一种活化的氨基甲酸酯,在温和条件下与氨基发生短暂反应,形成酰脲键。这些衍生物在质谱仪碰撞池中的试剂和氨基酸之间的结合位点提供选择性裂解,并产生源自试剂部分的特征片段。利用串联质谱的前体离子扫描模式,在色谱图上同时测量用试剂衍生的氨基酸。选择性裂解还可以通过选定的反应监测模式对氨基酸进行简单的同位素比分析,这适用于 13C 代谢通量分析。 TAHS 含有阳离子季胺,通过在选定的反应监测模式下进行测量,可以实现亚飞摩尔至阿托摩尔水平的氨基酸检测。我们还合成了甲基甲基取代的 TAHS、TAHS-d3,并证明 TAHS 和 TAHS-d3 的组合可用于使用单次 LC/MS/MS 测量来比较两个不同样品之间的氨基酸浓度。