Mass spectrometry imaging with laser-induced postionization
Mass spectrometry imaging with laser-induced postionization
复制标题
DOI：
10.1126/science.aaa1051
复制
发表时间：
2015-04-10
期刊：
影响因子：
56.9
通讯作者：
Dreisewerd, Klaus
中科院分区：
文献类型：
--
作者：
Soltwisch, Jens;Kettling, Hans;Dreisewerd, Klaus
基质辅助激光解吸/电离质谱成像（MALDI-MSI）可以同时记录组织切片中众多生物分子的横向分布，但其灵敏度受到有限电离的限制。我们使用波长可调谐位置电离激光器在气相中启动类似 MALDI 的二次电离过程。通过这种方式，我们可以将多种脂质类别、脂溶性维生素和糖类的离子产率提高两个数量级，并使用 5 微米宽的激光点在动物和植物组织中成像。启动二次电离过程的关键参数是离子源中冷却气体的压力、激光波长、脉冲能量和两个激光脉冲之间的延迟。该技术可以实现灵敏的 MALDI-MS 成像，横向分辨率在低微米范围内。
Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) can simultaneously record the lateral distribution of numerous biomolecules in tissue slices, but its sensitivity is restricted by limited ionization. We used a wavelength-tunable postionization laser to initiate secondary MALDI-like ionization processes in the gas phase. In this way, we could increase the ion yields for numerous lipid classes, liposoluble vitamins, and saccharides, imaged in animal and plant tissue with a 5-micrometer-wide laser spot, by up to two orders of magnitude. Critical parameters for initiation of the secondary ionization processes are pressure of the cooling gas in the ion source, laser wavelength, pulse energy, and delay between the two laser pulses. The technology could enable sensitive MALDI-MS imaging with a lateral resolution in the low micrometer range.