Mass Spectrometry Laboratory, GIGA-Research, University of Liege, 4000, Liege, Belgium.
Anal Chem. 2010 Nov 15;82(22):9248-53. doi: 10.1021/ac1017452. Epub 2010 Oct 28.
Due to its fastness and its easiness to use, MALDI-MS is currently an analytical tool widely used in glycomic applications. However, the MALDI ionization process could result in the so-called "in-source decay", or ISD, of analytes, leading to complex spectra. On the other hand, ISD opens the possibility to perform pseudo-MS(3) experiments. This phenomenon must therefore be controlled in order to be used on demand as a supplementary tool for the analysis of permethylated glycans by MALDI mass spectrometry. For this purpose, several matrices were tested and MALDI imaging was used to determine optimal conditions promoting or, inversely, avoiding ISD of permethylated glycans. 2,5-DHB was shown to be a versatile matrix allowing one to induce or prevent ISD according to the location of laser shots. Inversely, it was shown that 9-aminoacridine forms homogeneous spots and avoids completely ISD. This matrix would therefore be suitable for automatic analysis.
由于 MALDI-MS 快速且易于使用，目前已成为糖组学应用中广泛使用的分析工具。然而，MALDI 离子化过程可能导致分析物的所谓“源内降解”（ISD），从而产生复杂的光谱。另一方面，ISD 为进行伪 MS(3)实验提供了可能性。因此，必须控制这种现象，以便在需要时作为 MALDI 质谱法分析全甲基化聚糖的辅助工具使用。为此，测试了几种基质，并使用 MALDI 成像来确定促进或相反地避免全甲基化聚糖 ISD 的最佳条件。结果表明，2,5-DHB 是一种多功能基质，可根据激光点的位置诱导或防止 ISD。相反，结果表明 9-氨基吖啶形成均匀的斑点并完全避免 ISD。因此，该基质适合于自动分析。
