Department of Chemistry, University of Florida, Gainesville, FL, USA.
Methods Mol Biol. 2022;2437:3-19. doi: 10.1007/978-1-0716-2030-4_1.
The unambiguous identification of isobaric (i.e., same nominal mass) and isomeric (i.e., same exact mass) lipids remains a challenging yet vital aspect of imaging mass spectrometry (IMS) workflows. This chapter presents a methodology for the preparation of biological tissue samples and the use of a hybrid mass spectrometer to perform gas-phase charge inversion ion/ion reactions for improved lipid identification. This gas-phase ion/ion reaction method provides lipid structural information beyond what can be obtained via conventional tandem mass spectrometry (MS/MS) experiments. While this procedure is described here for the identification of phosphatidylcholine (PC) analyte cations using 1,4-phenylenedipropionic acid reagent dianions, it can readily be generalized to perform a diverse array of ion/ion reaction chemistries.
同重（即，相同名义质量）和同型（即，相同确切质量）脂质的明确识别仍然是成像质谱（IMS）工作流程中具有挑战性但至关重要的方面。本章介绍了一种用于制备生物组织样品的方法，以及使用混合质谱仪进行气相电荷反转离子/离子反应以提高脂质鉴定的方法。这种气相离子/离子反应方法提供了通过传统串联质谱（MS/MS）实验无法获得的脂质结构信息。虽然这里描述的程序是使用 1,4-亚苯基二丙酸试剂二阴离子来鉴定磷脂酰胆碱（PC）分析物阳离子，但它可以很容易地推广到进行各种离子/离子反应化学。
