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Updated: Jul 10, 2026

Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
Structural analysis of leukotriene C4 isomers using collisional activation and 157 nm photodissociation
Arugadoss Devakumar1, David K O'Dell, J Michael Walker
1Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.
Abstract:
The fragmentation of 5-hydroxy-6-glutathionyl-7,9,11,14-eicosatetraenoic acid [leukotriene C4 or LTC4 (5, 6)] and its isomeric counterpart LTC4 (14, 15) were studied by low and high-energy collisional induced dissociation (CID) and 157 nm photofragmentation. For singly charged protonated LTC4 precursors, photodissociation significantly enhances the signal intensities of informative fragment ions that are very important to distinguish the two LTC4 isomers and generates a few additional fragment ions that are not usually observed in CID experiments. The ion trap enables MSn experiments on the fragment ions generated by photodissociation. Photofragmentation is found to be suitable for the structural identification and isomeric differentiation of cysteinyl leukotrienes and is more informative than low or high-energy CID. We describe for the first time the structural characterization of the LTC4 (14, 15) isomer by mass spectrometry using CID and 157 nm light activation methods.
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