Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
Department of Energy Center for Advanced Bioenergy and Bioproducts Innovation, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, United States.
J Am Soc Mass Spectrom. 2021 May 5;32(5):1180-1188. doi: 10.1021/jasms.1c00013. Epub 2021 Apr 6.
Mass spectrometry imaging is well-suited to characterizing sample surfaces for their chemical content in a spatially resolved manner. However, when the surface contains small objects with significant empty spaces between them, more efficient approaches to sample acquisition are possible. Image-guided mass spectrometry (MS) enables high-throughput analysis of a diverse range of sample types, such as microbial colonies, liquid microdroplets, and others, by recognizing and analyzing selected location targets in an image. Here, we describe an imaging protocol and macroMS, an online software suite that can be used to enhance MS measurements of macroscopic samples that are imaged by a camera or a flatbed scanner. The web-based tool enables users to find and filter targets from the optical images, correct optical distortion issues for improved spatial location of selected targets, input the custom geometry files into an MS device to acquire spectra at the selected locations, and finally, perform limited data analysis and use visualization tools to aid locating samples containing compounds of interest. Using the macroMS suite, an enzyme mutant library of and nL droplet arrays of and have been assayed at a rate of ∼2 s/sample.
质谱成像非常适合以空间分辨的方式描述样品表面的化学含量。然而，当表面包含小物体且它们之间有空隙时，可能需要更有效的样本采集方法。图像引导质谱 (MS) 通过识别和分析图像中的选定位置目标，实现了对微生物菌落、液滴等多种样本类型的高通量分析。在这里，我们描述了一种成像方案和 macroMS，这是一个在线软件套件，可用于增强通过相机或平板扫描仪成像的宏观样本的 MS 测量。该基于网络的工具使用户能够从光学图像中找到和筛选目标，纠正光学失真问题以改善选定目标的空间位置，将自定义几何文件输入到 MS 设备中以在选定位置获取光谱，并最终执行有限的数据分析和使用可视化工具来辅助定位含有感兴趣化合物的样品。使用 macroMS 套件，以 ∼2 s/sample 的速度对 和 nL 液滴阵列的 和 酶突变体文库进行了检测。
