Isotope‐selective tandem mass spectrometry: a new tool for elucidation of fragmentation pathways
Isotope‐selective tandem mass spectrometry: a new tool for elucidation of fragmentation pathways
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同位素选择性串联质谱：阐明碎片途径的新工具
DOI：
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发表时间：
1998
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影响因子：
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通讯作者：
W. Lehmann
中科院分区：
文献类型：
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作者：
W. Lehmann
在三重四极杆质谱仪中，通过碰撞诱导解离选择性地碎裂由纳米电喷雾电离产生的非同位素富集的生物分子的同位素离子。使用这种技术，重同位素，如13 C或18 O，对碎片离子的同位素模式的影响显着增强相比，一组非质量选择的分子离子的解离。+1 Da同位素异构体离子的解离产生碎片离子双峰，当前体分子离子的经验式已知时，允许测定碎片中的碳原子数。+2 Da同位素异构体离子的解离产生碎片离子三联体。根据碎片的碳原子数，这些三重态的离子丰度可以确定氧等杂元素，其中含有比其主同位素重两个质量单位的稳定同位素。该技术被应用于质子化的1-烯基-2-酰基-磷脂酰乙醇胺（plasmenyl-phosphatidyleethanolamine）的两个主要碎片离子的元素组成的测定。结果表明，它们是通过重排形成的，产生两个互补的碎片离子，分别携带1-烯基和2-酰基取代基。碎片离子的元素组成的信息可以通过同位素选择性串联电喷雾质谱法使用低皮摩尔范围内的样品量获得。
Tbe isotopomeric ions of non-isotope-enriched biomolecules generated by nanoelectrospray ionization were selectively fragmented by collision-induced dissociation in a triple-quadrupole mass spectrometer. Using this technique, the influence of heavy isotopes, such as 13 C or 18 O, on the isotopic pattern of fragment ions is significantly enhanced compared with the dissociation of an entire group of non-mass selected molecular ions. Dissociation of the +1 Da isotopomeric ions results in fragment ion doublets, allowing the determination of the number of carbon atoms in the fragment when the empirical formula of the precursor molecular ion is known. Dissociation of the + 2 Da isotopomeric ions results in fragment ion triplets. On the basis of the carbon atom number of a fragment, the ion abundances of these triplets allow the determination of a heteroelement such as oxygen, containing a stable isotope two mass units heavier than the value of its principle isotope. The technique was applied to the determination of the elemental composition of the two main fragment ions of protonated 1-alkenyl-2-acyl-phosphatidylethanolamine (plasmenyl-phosphatidylethanolamine). The results show that they are formed by a rearrangement resulting in two complementary fragment ions carrying the 1-alkenyl and 2-acyl substituent, respectively. Information on the elemental composition of fragment ions can be obtained by isotope-selective tandem electrospray mass spectrometry using sample amounts in the low picomole range.