State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University, Zhongguancun Street, Hai Dian District, Beijing 100084, China.
Tsinghua Shenzhen International Graduate School, Shenzhen University Town, Lishui Road, Xili Town, Nanshan District, Shenzhen 518055, China.
Anal Chem. 2021 Feb 2;93(4):2114-2124. doi: 10.1021/acs.analchem.0c03888. Epub 2021 Jan 14.
Lipid imaging plays an important role in the research of some diseases, such as cancers. Unsaturated lipids are often present as isomers that can have different functions; however, traditional tandem mass spectrometry imaging (MSI) cannot differentiate between different isomers, which presents difficulties for the pathological study of lipids. Herein, we propose a method for the MSI of the C═C double-bond isomers of unsaturated lipids based on oxidative reactions coupled with air flow-assisted desorption electrospray ionization, which can conveniently achieve rapid MSI of unsaturated lipids at an isomeric level. Using this method, tissue sections can be scanned directly with MSI after only 10 min of accelerated oxidation. This method was used for the imaging of mouse lung cancer tissues, revealing a distributional difference in the unsaturated lipid isomers of normal and pathological regions. Through the MSI of unsaturated lipids at an isomeric level in tissues infected with cancer cells, the regions where the isomers were enriched were exhibited, indicating that these regions were the most concentrated regions of cancer cells. This method provides a convenient platform for studying the functional effects of the isomers of unsaturated lipids in pathological tissues.
脂质成像在某些疾病（如癌症）的研究中起着重要作用。不饱和脂质通常以异构体的形式存在，这些异构体可能具有不同的功能；然而，传统的串联质谱成像（MSI）无法区分不同的异构体，这给脂质的病理研究带来了困难。在此，我们提出了一种基于氧化反应与气流辅助解吸电喷雾电离相结合的方法，用于对不饱和脂质的 C═C 双键异构体进行 MSI，该方法可以方便地实现对不饱和脂质的快速异构体水平的 MSI。使用这种方法，只需加速氧化 10 分钟，就可以直接用 MSI 对组织切片进行扫描。该方法用于对小鼠肺癌组织进行成像，揭示了正常和病理区域不饱和脂质异构体的分布差异。通过对癌细胞感染组织中不饱和脂质异构体的 MSI，可以显示出异构体富集的区域，表明这些区域是癌细胞最集中的区域。该方法为研究病理组织中不饱和脂质异构体的功能效应提供了一个便捷的平台。
