Determining the relative amounts of positional isomers in complex mixtures of triglycerides using reversed-phase high-performance liquid chromatography-tandem mass spectrometry
Determining the relative amounts of positional isomers in complex mixtures of triglycerides using reversed-phase high-performance liquid chromatography-tandem mass spectrometry
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DOI：
10.1007/s11745-004-1230-6
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发表时间：
2004-03-01
期刊：
影响因子：
1.9
通讯作者：
Evans, JJ
中科院分区：
文献类型：
--
作者：
Malone, M;Evans, JJ
一个反相高效液相色谱-串联质谱法（RP-HPLC-MS-MS）的方法进行了改进的复杂的混合物的TAG的位置分析。与传统的基于消化的TAG位置分析方法相比，该方法具有快速、易于自动化和特异性的优点。碰撞诱导解离（CID）的氨化TAG在离子阱质谱仪产生的光谱是依赖于FA的位置。主要DAG片段由来自氨化TAG物质的FA部分的损失形成。FA在外围位置的损失比他们在中心位置的损失更有利。RP-HPLC和CID的组合产生的光谱不受同位素效应的影响，而同位素效应会使现有方法中的光谱解释复杂化。除了CID工艺中固有的选择性之外，该组合还提供了基于TAG的色谱分离的选择性。用来自SOS/SSO、OSO/OOS和PSO/POS/SPO位置异构体系统的TAG的二元混合物（其中S为18：0，硬脂酸; 0为18：1（顺式-9），油酸; P为16：0，棕榈酸）进行概念验证实验。分数DAG片段强度对二元混合物的分数组成的图是线性的。这些图被用来确定这些异构体系统中的每一个在各种植物油和动物脂肪的分数组成。目前的局限性，未来的发展，这种方法的应用进行了讨论。
A reversed-phase HPLC-tandem mass spectrometry (RP-HPLC-MS-MS) method was refined for the positional analysis of complex mixtures of TAG. This method has the advantages of speed, ease of automation, and specificity over traditional digestion-based methods for the positional analysis of TAG. Collision-induced dissociation (CID) of ammoniated TAG in an ion-trap mass spectrometer produced spectra that were dependent on the FA position. Dominant DAG fragments were formed from the loss of a FA moiety from the ammoniated TAG species. The loss of FA in the outer positions was favored over their loss in the central position. The combination of RP-HPLC and CID produced spectra that were free of the isotope effects that can complicate spectral interpretation in existing methods. The combination also provided selectivity based on the chromatographic fractionation of TAG, in addition to the selectivity inherent in the CID process. Proof-of-concept experiments were performed with binary mixtures of TAG from the SOS/SSO, OSO/OOS, and the PSO/POS/SPO positional isomer systems (where S is 18:0, stearic acid; 0 is 18:1 (cis-9), oleic acid; and P is 16:0, palmitic acid). Plots of fractional DAG fragment intensities vs. fractional composition of the binary mixtures were linear. These plots were used to determine the fractional composition of each of these isomeric systems in a variety of vegetable oils and animal fats. Current limitations, future developments, and applications of this method are discussed.