Generation of CsI cluster ions for mass calibration in matrix-assisted laser desorption/ionization mass spectrometry.
A simple method was developed for the generation of cesium iodide (CsI) cluster ions up to m/z over 20,000 in matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). Calibration ions in both positive and negative ion modes can readily be generated from a single MALDI spot of CsI(3) with 2-[(2E)-3-(4-tert-butylphenyl)-2-methylprop-2-enylidene] malononitrile (DCTB) matrix. The major cluster ion series observed in the positive ion mode is [(CsI)(n)Cs](+), and in the negative ion mode is [(CsI)(n)I](-). In both cluster series, ions spread evenly every 259.81 units. The easy method described here for the production of CsI cluster ions should be useful for MALDI MS calibrations.
Lou
Xianwen
X
Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, Eindhoven, The Netherlands. x.w.lou@tue.nl
van Dongen
Joost L J
JL
Meijer
E W
EW