We describe the construction and application of a new MALDI source for FT-ICR mass spectrometry imaging. The source includes a translational X-Y positioning stage with a 10 × 10 cm range of motion for analysis of large sample areas, a quadrupole for mass selection, and an external octopole ion trap with electrodes for the application of an axial potential gradient for controlled ion ejection. An off-line LC MALDI MS/MS run demonstrates the utility of the new source for data- and position-dependent experiments. A FT-ICR MS imaging experiment of a coronal rat brain section yields ∼200 unique peaks from m/z 400–1100 with corresponding mass-selected images. Mass spectra from every pixel are internally calibrated with respect to polymer calibrants collected from an adjacent slide.

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Persistent URL dx.doi.org/10.1007/s13361-010-0003-x
Journal J. Am. Soc. Mass Spectrom.
Smith, D.F, Aizikov, K, Duursma, M.C, Giskes, F.G, Spaanderman, D.-J, McDonnell, L.A, … Heeren, R.M.A. (2011). An external matrix-assisted laser desorption ionization source for flexible FT-ICR mass spectrometry imaging with internal calibration on adjacent samples. J. Am. Soc. Mass Spectrom., 22(1), 130–137. doi:10.1007/s13361-010-0003-x