Chaurand Pierre, Schriver Kenneth E, Caprioli Richard M
Mass Spectrometry Research Center and Department of Biochemistry, Vanderbilt University, Nashville Tennessee 37232-8575, USA.
J Mass Spectrom. 2007 Apr;42(4):476-89. doi: 10.1002/jms.1180.
In previous work, we have reported using a MALDI imaging time-of-flight mass spectrometer for the detection of protein ions from tissue sections with spatial resolution of 25 microm. We present here imaging mass spectrometry results obtained with a high-resolution scanning MALDI time-of-flight mass spectrometer, equipped with a coaxial laser illumination ion source, capable of achieving irradiation areas as small as 40 microm(2) (ca 7 microm diameter). MALDI-generated analyte ion signals from these very small irradiation volumes can be observed in a molecular weight range up to 27,000. High-resolution imaging mass spectrometry images were successfully generated from matrix thin film samples and tissue sections with scanning resolutions at and below 10 microm. This work also provides fundamental characterization of the ion signal dependence as a function of various focus and fluence parameters that will be required for extension to tissue imaging at the subcellular level.
在之前的工作中，我们报道了使用基质辅助激光解吸电离成像飞行时间质谱仪从组织切片中检测蛋白质离子，其空间分辨率为25微米。我们在此展示了使用高分辨率扫描基质辅助激光解吸电离飞行时间质谱仪获得的成像质谱结果，该质谱仪配备同轴激光照射离子源，能够实现小至40微米²（直径约7微米）的照射面积。在高达27,000的分子量范围内，可以观察到来自这些非常小的照射体积的基质辅助激光解吸电离产生的分析物离子信号。通过扫描分辨率为10微米及以下的基质薄膜样品和组织切片成功生成了高分辨率成像质谱图像。这项工作还提供了离子信号依赖性作为各种聚焦和能量密度参数函数的基本特征，这对于扩展到亚细胞水平的组织成像将是必需的。
