MALDI MS imaging was initially developed to focus on high molecular weight compounds such as proteins and peptides. However, with the expanding applications of MALDI MS imaging, the interests have shifted to include smaller molecules such as lipids, pharmaceuticals, and pharmaceutical metabolites. Conventional MALDI - reflectron TOFMS has difficulty discerning small molecule signals from those of matrix. In the case of MALDI MS imaging, signals from unwanted molecules on the specimen surface will often interfere with signals from the target analytes. High selectivity by means of high mass-resolving power is essential for obtaining reliable target analyte spatial distributions. It is also important to maintain high mass-resolution and mass-accuracy for a long time even when measuring a sample surface with a large area and non-uniformity. SpiralTOF™-plus 2.0 is the only MALDI-TOFMS that meets imaging requirements with ultra-high mass-resolution and long flight distance to minimize loss of mass resolution due to sample surface non-uniformity. In addition, it also supports high-speed mass imaging analysis.
Mass Spectrometry Imaging Analysis of Lipids in Mouse Brain Tissue Section
Averaged mass spectrum of a mouse brain tissue section
PE: Phosphatidyl ethanolamine, PC: Phosphatidyl Choline, GalCer: Galactosylceramide
The data were acquired in a joint research project with the Mass Spectrometry Group, Project Research Center for Fundamental Sciences, Graduate School of Science, Osaka University.
The tissue section specimen was provided by Awazu laboratory, Division of Sustainable Energy and Environmental Engineering, Graduate School of Engineering, Osaka University.
Mass spectrometry imaging of polymers
Mass spectrometry imaging can be applied to polymers. Two spots are prepared by adding two antioxidants - Irgafos 168 (BASF) and Irganox 1010 (BASF) - to polymethylmethacrylate (PMMA). The ultraviolet irradiation was performed to the right spot only and its degradation was visualized by using mass spectrometry imaging. For polymers, it is possible to visualize the quantitative change in both polymers and additives. It is also possible to capture the changes in the average molecular weight and polydispersity.
MS imaging of PMMA, Irgafos 168, and Irganox 1010