In this study, we applied a new IR laser-beam-focusing technique to enable sub-100 μm spatial resolution in laser ablation atmospheric pressure photoionization (LAAPPI) and laser ablation electrospray ionization (LAESI) mass spectrometry imaging (MSI). After optimization of operational parameters, both LAAPPI- and LAESI-MSI with a spatial resolution of 70 μm produced high-quality MS images, which allowed accurate localization of metabolites and lipids in the mouse and rat brain. Negative and positive ion LAAPPI- and LAESI-MS detected many of the same metabolites and lipids in the brain. Many compounds were also detected either by LAAPPI- or LAESI-MS, indicating that LAAPPI and LAESI are more complementary than alternative methods.

中文翻译：

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激光消融大气压光电离（LAAPPI）和激光消融电喷雾电离（LAESI）对啮齿动物大脑进行100微米以下的空间分辨率环境质谱成像。

在这项研究中，我们应用了一种新的IR激光束聚焦技术，以在激光烧蚀大气压光电离（LAAPPI）和激光烧蚀电喷雾电离（LAESI）质谱成像（MSI）中实现小于100μm的空间分辨率。优化操作参数后，空间分辨率为70μm的LAAPPI-和LAESI-MSI均可产生高质量的MS图像，从而可以在小鼠和大鼠的大脑中准确定位代谢产物和脂质。负离子和正离子LAAPPI-和LAESI-MS检测到大脑中许多相同的代谢物和脂质。通过LAAPPI-或LAESI-MS也检测到许多化合物，这表明LAAPPI和LAESI比其他方法更具互补性。