Department of Chemistry, University of Vermont, 82 University Place, Burlington, VT 05405, USA.
Molecules. 2013 Dec 5;18(12):14977-88. doi: 10.3390/molecules181214977.
Binary stable isotope labeling couple with LC-ESI-MS has been used as a powerful non-targeted approach for the relative quantification of lipids, amino acids, and many other important metabolite classes. A multiplexed approach using three or more isotopic labeling reagents greatly reduces analytical run-time while maintaining excellent sensitivity and reproducibility. Three isotopic cholamine labeling reagents have been developed to take advantage of the pre-ionized character of cholamine, for ESI, and the ease by which stable isotopes can be incorporated into the cholamine structure. These three cholamine labeling reagents have been used to relatively quantify three fatty acid samples simultaneously. The quantification resulted in the observation of 12 fatty acids that had an average absolute error of 0.9% and an average coefficient of variation of 6.1%. Caged versus cage-free isotope labeling experiments showed that cage-free eggs have an increased level of omega-3 fatty acids as compared to caged eggs. This multiplexed fatty acid analysis provides an inexpensive and expedited tool for broad-based lipid profiling that will further aid discoveries in the mechanisms of fatty acid action in cells.
二元稳定同位素标记与 LC-ESI-MS 联用已被用作一种强大的非靶向方法，用于相对定量脂质、氨基酸和许多其他重要代谢物类别。使用三种或更多种同位素标记试剂的多路复用方法可以大大减少分析运行时间，同时保持出色的灵敏度和重现性。已经开发了三种同位素胆碱标记试剂，以利用胆碱的预电离特性和稳定同位素易于掺入胆碱结构的特点。这三种胆碱标记试剂已被用于同时相对定量三种脂肪酸样品。定量结果观察到 12 种脂肪酸，平均绝对误差为 0.9%，平均变异系数为 6.1%。笼养与非笼养同位素标记实验表明，与笼养鸡蛋相比，非笼养鸡蛋中的 ω-3 脂肪酸水平更高。这种多路复用脂肪酸分析为广泛的脂质分析提供了一种廉价且快速的工具，这将进一步帮助发现脂肪酸在细胞中的作用机制。
