Lutomski Corinne A, El-Baba Tarick J, Inutan Ellen D, Manly Cory D, Wager-Miller James, Mackie Ken, Trimpin Sarah
Department of Chemistry, Wayne State University , Detroit, Michigan 48202, United States.
Anal Chem. 2014 Jul 1;86(13):6208-13. doi: 10.1021/ac501788p. Epub 2014 Jun 18.
This represents the first report of laserspray ionization vacuum (LSIV) with operation directly from atmospheric pressure for use in mass spectrometry. Two different types of electrospray ionization source inlets were converted to LSIV sources by equipping the entrance of the atmospheric pressure inlet aperture with a customized cone that is sealed with a removable glass plate holding the matrix/analyte sample. A laser aligned in transmission geometry (at 180° relative to the inlet) ablates the matrix/analyte sample deposited on the vacuum side of the glass slide. Laser ablation from vacuum requires lower inlet temperature relative to laser ablation at atmospheric pressure. However, higher inlet temperature is required for high-mass analytes, for example, α-chymotrypsinogen (25.6 kDa). Labile compounds such as gangliosides and cardiolipins are detected in the negative ion mode directly from mouse brain tissue as intact doubly deprotonated ions. Multiple charging enhances the ion mobility spectrometry separation of ions derived from complex tissue samples.
这是关于激光喷雾电离真空（LSIV）的首篇报道，该技术可在大气压下直接操作并用于质谱分析。通过在大气压入口孔径的入口处配备一个定制的圆锥体，并使用一块装有基质/分析物样品的可移动玻璃板进行密封，将两种不同类型的电喷雾电离源入口转换为LSIV源。以透射几何构型排列的激光（相对于入口呈180°）烧蚀沉积在载玻片真空侧的基质/分析物样品。相对于大气压下的激光烧蚀，真空条件下的激光烧蚀所需的入口温度更低。然而，对于高质量分析物，例如α-胰凝乳蛋白酶原（25.6 kDa），则需要更高的入口温度。不稳定化合物，如神经节苷脂和心磷脂，在负离子模式下可直接从小鼠脑组织中检测到完整的双去质子化离子。多重电荷增强了源自复杂组织样品的离子的离子迁移谱分离。
