title: A column-switching LC/MS/ESI method for detecting tetrodotoxin and Aconitum alkaloids in serum.
abstract: A liquid chromatography-mass spectrometry-electrospray ionization (LC/MS/ESI) method coupled with a column-switching technique has been developed for the determination of tetrodotoxin (TTX) and Aconitum alkaloids and their metabolites, such as aconitine, mesaconitine, hypaconitine, jesaconitine, benzoylaconine, benzoylmesaconine, benzoylhypaconine and 14-anisoylaconine, in serum. An on-column column-switching technique was employed to analyze TTX and Aconitum alkaloids and their metabolites without pretreatment of the serum. Combination of a multimode column with reversed phases and cation exchange for TTX, and use of a multimode column with reversed phases and a hydrophobic polymer column for Aconitum alkaloids and their metabolites provided successful separation and MS determination in ESI positive mode. A 100 microl serum sample was directly injected into a precolumn. For TTX monitored at m/z 320.1 in the selected ion monitoring mode, the calibration curve was linear within the range 0.1-100 ng/ml and the limit of detection was 0.1 ng/ml. For aconitine, mesaconitine, hypaconitine and jesaconitine, linear calibration curves were obtained up to 500 ng/ml and the limit of detection ranged from 0.2 to 1 ng/ml. For benzoylaconine, benzoylmesaconine, benzoylhypaconine and 14-anisoylaconine, linear calibration curves were obtained up to 500 ng/ml and the limit of detection ranged from 2 to 50 ng/ml. Recoveries from serum samples were within the range 78-119% for all the compounds studied.
authors.affiliation: Department of Legal Medicine, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo 113-8602, Japan. mh@nms.ac.jp
authors.forename: Makiko
authors.initials: M
authors.lastname: Hayashida
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Hayakawa
authors.forename: Kentaro
authors.initials: K
authors.lastname: Wada
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yamada
authors.forename: Makoto
authors.initials: M
authors.lastname: Nihira
authors.forename: Youkichi
authors.initials: Y
authors.lastname: Ohno
mesh_terms: D000157:Aconitine / Q000031:analogs & derivatives* / Q000097:blood*; D000470:Alkaloids / Q000097:blood; D002138:Calibration; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013779:Tetrodotoxin / Q000097:blood*
chemical_list: C479201:14-anisoylaconine; D000470:Alkaloids; C479202:benzoylhypaconine; C047307:benzoylaconine; D013779:Tetrodotoxin; D000157:Aconitine