Premium
Metastable ions arising from pseudomolecular [M H] − ions produced by fast‐atom bombardment negative‐ion mass spectrometry of ecdysteroids
Author(s) -
Evershed Richard P.,
Prescott Mark C.,
Kabbouh Mohamed,
Rees Huw H.
Publication year - 1989
Publication title -
rapid communications in mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.528
H-Index - 136
eISSN - 1097-0231
pISSN - 0951-4198
DOI - 10.1002/rcm.1290031010
Subject(s) - chemistry , fast atom bombardment , ion , metastability , mass spectrometry , atom (system on chip) , radiochemistry , analytical chemistry (journal) , chromatography , organic chemistry , computer science , embedded system
Metastable ions arising from pseudomolecular [M H] − ions produced by fast‐atom bombardment negative‐ion mass spectrometry of a range of free ecdysteroids, ecdysteroid conjugates and polar metabolites were investigated by means of linked scanning at constant B/E. Free ecdysteroids displayed daughter‐ion spectra which allow 20‐hydroxyecdysteroids and ecdysteroids lacking C‐20 hydroxylation to be readily distinguished. The ejection of acetic acid from acetylated ecdysteroids was also readily detectable. Characteristic metastable‐ion decomposition of ecdysteroid acids was not observed, presumably as a result of charge localization. High‐mass daughter ions were also lacking in the case of phosphate conjugates.