title: Determination of strophanthidin in ingesta and plant material by LC-MS/MS.
abstract: An LC-MS/MS method was developed for the semiquantitative determination of strophanthidin glycosides in ingesta from animals. Strophanthidin glycosides were simultaneously extracted and hydrolyzed to the strophanthidin aglycone using aqueous methanolic hydrochloric acid and the extracts cleaned up using solid-phase extraction. Extracts were analyzed using reverse-phase HPLC coupled with positive ion electrospray mass spectrometry. Characteristic product ion spectra were produced by fragmentation of the [M + H](+) precursor ion for each analyte. Quantitation was performed using the internal standard method with digitoxigenin serving as the internal standard. The method detection limit was calculated to be 0.075 microg/g, and the limit of quantitation was calculated to be 0.24 microg/g for strophanthidin in control rumen samples. This method was used in diagnostic investigations to confirm fatal strophanthidin glycoside poisonings in horses.
authors.affiliation: California Animal Health and Food Safety Laboratory System, University of California, Davis, California 95616, USA. msfiligenzi@ucdavis.edu
authors.forename: Michael S
authors.initials: MS
authors.lastname: Filigenzi
authors.forename: Leslie W
authors.initials: LW
authors.lastname: Woods
authors.forename: Marcia C
authors.initials: MC
authors.lastname: Booth
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Tor
authors.forename: Birgit
authors.initials: B
authors.lastname: Puschner
mesh_terms: D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004064:Digestive System / Q000737:chemistry* / Q000378:metabolism; D006331:Heart Diseases / Q000139:chemically induced / Q000662:veterinary; D006734:Horse Diseases / Q000139:chemically induced / Q000378:metabolism; D006736:Horses; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000737:chemistry; D010944:Plants / Q000737:chemistry*; D012417:Rumen / Q000737:chemistry / Q000378:metabolism; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization; D013327:Strophanthidin / Q000032:analysis* / Q000633:toxicity
chemical_list: D013327:Strophanthidin