title: Liquid chromatographic determination of progestogens in animal fat.
abstract: A liquid chromatographic method was developed for determination of 3 progestogens-melengestrol acetate, megestrol acetate, and chlormadinone acetate-found in edible tissue at concentrations between 10 and 1000 ppb. These progestogens are commonly used as feed additives to control herd estrus and to improve feed efficiency. Rendered fat was extracted with acetonitrile, washed with hexane, and dried. The remaining lipids were saponified with sodium hydroxide and precipitated with magnesium chloride. The progestogens were extracted from the basic solution with hexane, dried, and cleaned up on a cyanopropyl solid-phase extraction column in the normal-phase mode. The eluate was dried and reconstituted with acetonitrile-water (7 + 3, v/v). Chromatography was performed on a 5 microns high-carbon load C18 column with acetonitrile-water (7 + 3, v/v) at 1 mL/min and UV detection at 291 nm. Recoveries from fortified samples ranged from 84 to 116%. The limit of quantitation was 10 ppb for both beef and pork. The detection limit was 3 ppb.
authors.affiliation: Agriculture Canada, Health of Animals Laboratory, Saskatoon, SK, Canada.
authors.forename: M T
authors.initials: MT
authors.lastname: Andresen
authors.forename: A C
authors.initials: AC
authors.lastname: Fesser
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000273:Adipose Tissue / Q000737:chemistry* / Q000378:metabolism; D000818:Animals; D002417:Cattle; D002715:Chlormadinone Acetate / Q000032:analysis*; D002853:Chromatography, Liquid; D004350:Drug Residues / Q000032:analysis*; D006586:Hexanes / Q000737:chemistry; D015636:Magnesium Chloride / Q000737:chemistry; D019290:Megestrol Acetate / Q000032:analysis*; D008552:Melengestrol Acetate / Q000032:analysis*; D012015:Reference Standards; D015203:Reproducibility of Results; D012972:Sodium Hydroxide / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013552:Swine; D014867:Water / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D006586:Hexanes; D015636:Magnesium Chloride; D014867:Water; D002715:Chlormadinone Acetate; D008552:Melengestrol Acetate; D012972:Sodium Hydroxide; D019290:Megestrol Acetate; C032159:acetonitrile