Multigrid MALDI mass spectrometry imaging (mMALDI MSI)
Multigrid MALDI mass spectrometry imaging (mMALDI MSI)
复制标题
DOI：
10.1007/s00216-016-9465-4
复制
发表时间：
2016-04
影响因子：
4.3
通讯作者：
Annett Urbanek;Stefan Hölzer;K. Knop;U. Schubert;F. von Eggeling
中科院分区：
文献类型：
--
作者：
Annett Urbanek;Stefan Hölzer;K. Knop;U. Schubert;F. von Eggeling
基质辅助激光解吸电离质谱成像（MALDI MSI）是一种重要的组织切片空间分辨分子分析技术。基质的选择在很大程度上影响所得质谱。对于广泛和同时的分析，需要将不同的基质应用于一个组织样品。迄今为止，每次实验只能将单个基质应用于组织切片。然而，重复去除基质使得该方法耗时并且对组织样品造成损害。为了克服这些缺点，我们开发了一种多网格MALDI MSI技术（mMALDI MSI），该技术依赖于自动喷墨打印将不同的矩阵放置到预定义的点网格上。我们使用冷却打印头来防止打印头喷嘴中低粘度溶剂的气穴现象。通过使用减少液滴体积的三脉冲程序实现了点网格的空间分辨率的提高。基质可以直接应用于解冻固定的组织样品，或者通过预涂载玻片，然后固定组织样品。在MALDI成像过程中，我们能够用激光精确地瞄准不同的矩阵点网格，同时产生不同的质谱。与标准方法不同，预点样方法优化了光谱质量，避免了分析物离域，并支持随后的苏木精和伊红（H&E）染色。图形摘要预点样多重网格MALDI MSI工作流程的方案
Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) is an important technique for the spatially resolved molecular analysis of tissue sections. The selection of matrices influences the resulting mass spectra to a high degree. For extensive and simultaneous analysis, the application of different matrices to one tissue sample is desirable. To date, only a single matrix could be applied to a tissue section per experiment. However, repetitive removal of the matrix makes this approach time-consuming and damaging to tissue samples. To overcome these drawbacks, we developed a multigrid MALDI MSI technique (mMALDI MSI) that relies on automated inkjet printing to place differing matrices onto predefined dot grids. We used a cooled printhead to prevent cavitation of low viscosity solvents in the printhead nozzle. Improved spatial resolution of the dot grids was achieved by using a triple-pulse procedure that reduced droplet volume. The matrices can either be applied directly to the thaw-mounted tissue sample or by precoating the slide followed by mounting of the tissue sample. During the MALDI imaging process, we were able to precisely target different matrix point grids with the laser to simultaneously produce distinct mass spectra. Unlike the standard method, the prespotting approach optimizes the spectra quality, avoids analyte delocalization, and enables subsequent hematoxylin and eosin (H&E) staining.Graphical AbstractScheme of the pre-spotted multigrid MALDI MSI workflow