Pre-column derivatization and gas chromatographic determination of alkaloids in bulbs of Fritillaria

A method of precolumn derivatization GC with FID detection was developed fo r a simultaneous analysis of five major steroidal alkaloids of Fritillaria species, namely ebeiedine, ebeiedinone, verticine, verticinone and imperial ine. Derivatization was carried out by trimethylsilylation of the hydroxyl- containing Fritillaria alkaloids to the corresponding trimethylsilylates wi th trimethylsilylimidazole. Reaction conditions were optimised and the alka loids derivatives were characterised by on-line GC-MS. The validated GC met hod demonstrated a good linearity at the sampling ranges used. This analyti cal method is simple, convenient and reproducible. The developed assay was successfully applied to the determination of the major pharmacologically ac tive alkaloids in three commonly used antitussive Fritillaria species: F. c irrhosa, F. thumbergii and F. pallidiflora. (C) 1999 Elsevier Science B.V. All rights reserved.