Complete structural elucidation of triacylglycerols by tandem sector mass spectrometry
Complete structural elucidation of triacylglycerols by tandem sector mass spectrometry
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DOI：
10.1021/ac9805192
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发表时间：
1998-10-15
影响因子：
7.4
通讯作者：
Gross, ML
中科院分区：
文献类型：
--
作者：
Cheng, CF;Gross, ML
建立了一种用高能碰撞活化串联质谱（MS/MS）解析三酰甘油完整结构的方法。（+）离子（如果满足。= Li、Na和Cs）进行电荷远程和电荷驱动的断裂。我们着重研究了ESI产生的[M + NH_4]（+）和[M + Na]（+）离子以及FAB产生的[M + Na]（+）离子的碎片离子。ESI产生的[M + NH 4]（+）离子碎裂产生四种类型的离子，[M + NH 4-RnCOONH 4]（+）、[RnCO + 128]（+）、[RnCO + 74]（+）和RnCO+离子，由此获得每个酰基的碳数和不饱和度。此外，三个系列的离子产生的电荷远程碎裂（CRF），并分析其图案给出的位置和数量的双键上的酰基。然而，[M + NH 4]（+）离子的碰撞活化解离不能提供有关甘油主链上每个酰基位置的信息。另一方面，ESI-和FAB-产生的[M + Na]（+）离子碎片形成八种类型的离子（称为A-J离子），这些离子与CRF产生的离子一样，具有高度的结构信息。某些系列成员的缺失也带来了有用的结构信息。这些模式的解释使人们能够获得碳的数量，不饱和度，双键的位置，以及酰基在甘油主链上的位置。
We developed a method to elucidate the complete structure of triacylglycerols by means of high-energy collisional activation tandem mass spectrometry (MS/MS), Both ESI- and FAB-produced [M + NH4](+) and [M + met.](+) ions (where met. = Li, Na, and Cs) of triacylglycerols undergo charge-remote and charge-driven fragmentations. We emphasize the study of fragment ions from ESI-produced [M + NH4](+) and [M + Na](+) ions and FAB-produced [M + Na](+) ions. ESI-produced [M + NH4](+) ions fragment to produce four types of ions, [M + NH4 - RnCOONH4](+), [RnCO + 128](+), [RnCO + 74](+), and RnCO+ ions, from which the carbon number and the degree of unsaturation of each acyl group are obtained. In addition, three series of ions are produced by charge-remote fragmentations (CRFs), and analysis of their patterns gives the position and the number of double bonds on the acyl groups. Information about the position of each acyl group on the glycerol backbone, however, is not provided by collisionally activated dissociation of [M + NH4](+) ions. On the other hand, ESI- and FAB-produced [M + Na](+) ions fragment to form eight types of ions (named A-J ions) that, like those produced by CRF, are highly structurally informative. The absence of certain series members also carries useful structural information. Interpretation of these patterns enables one to obtain the number of carbons, degrees of unsaturation, and location of double bonds, as well as the positions of acyl groups on the glycerol backbone.