ESI-MS characteristic spectra of alkaloids in Bulbus Fritillariae / 中草药

ABSTRACT

Objective To develop the characteristic ESI-MS spectra of five Bulbus Fritillariae species and to be used for identification of Bulbus Fritillariae species.Methods The Bulbus Fritillariae medicinal materials were dipped in 18% ammonia solution,then the alkaloids were extracted by ultrasonic using the mixed solvent of ether-chloroform-ethanol(25∶8∶2.5).The extracts were analyzed directly by ESI-MS in positive ion mode.Results Bulbus alkaloids easily formed molecular ions(~+) in MS and dimerized easily in alcohol solution,which did not dimerize in acidity solution.Collision induced dissociation(S-CID) made these alkaloids easily lose a molecule of H_2O.The MS spectra of the extracts of five Bulbus Fritillariae species indicated that the major molecular ions were similar to each other,but different varieties showed very different relative abundances of these molecular ions.Conclusion The total alkaloid extracts of five Bulbus Fritillariae species have strong characteristic ESI-MS spectra and these spectra are of good reproducibility and precision,respectively.These characteristic spectra are useful for the identification of Bulbus Fritillariae species.