Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
J Am Soc Mass Spectrom. 2009 Dec;20(12):2229-37. doi: 10.1016/j.jasms.2009.08.011. Epub 2009 Aug 27.
Matrix-enhanced surface-assisted laser desorption ionization mass spectrometry imaging (ME-SALDI MSI) has been previously demonstrated as a viable approach to improving MS imaging sensitivity. We describe here the employment of ionic matrices to replace conventional MALDI matrices as the coating layer with the aims of reducing analyte redistribution during sample preparation and improving matrix vacuum stability during imaging. In this study, CHCA/ANI (alpha-cyano-4-hydroxycinnamic acid/aniline) was deposited atop tissue samples through sublimation to eliminate redistribution of analytes of interest on the tissue surface. The resulting film was visually homogeneous under an optical microscope. Excellent vacuum stability of the ionic matrix was quantitatively compared with the conventional matrix. The subsequently improved ionization efficiency of the analytes over traditional MALDI was demonstrated. The benefits of using the ionic matrix in MS imaging were apparent in the analysis of garlic tissue sections in the ME-SALDI MSI mode.
基质增强表面辅助激光解吸电离质谱成像（ME-SALDI MSI）已被证明是一种提高 MS 成像灵敏度的可行方法。我们在这里描述了使用离子基质替代传统的 MALDI 基质作为涂层的方法，旨在减少样品制备过程中分析物的再分配，并提高成像过程中基质的真空稳定性。在这项研究中，CHCA/ANI（alpha-氰基-4-羟基肉桂酸/苯胺）通过升华沉积在组织样品上，以消除组织表面上感兴趣的分析物的再分配。在光学显微镜下，得到的薄膜在视觉上是均匀的。离子基质的出色真空稳定性与传统基质进行了定量比较。随后证明了与传统 MALDI 相比，分析物的离子化效率得到了提高。在 ME-SALDI MSI 模式下分析大蒜组织切片时，离子基质在 MS 成像中的优势明显。
