title: Analysis of 17β-estradiol, estriol and estrone in American eel (Anguilla rostrata) tissue samples using liquid chromatography coupled to electrospray differential ion mobility tandem mass spectrometry.
abstract: BACKGROUND
  17β-Estradiol (E2), estrone (E1) and estriol (E3) are steroid hormones responsible for the regulation of the female reproductive system. Estradiol is planned to be used to feminize eels in aquaculture in order to improve their size and marketability. The residual levels of these hormones in fish tissue must be monitored to meet the requirements of food regulatory agencies. Few studies have studied these hormones in complex biological matrices such as fish tissue.
  
  
  METHODS
  We developed a method to analyze E1, E2 and E3 in fish tissue using liquid chromatography in combination with differential ion mobility spectrometry (DMS) and tandem mass spectrometry (MS/MS). The mass spectrometer was operated in negative polarity selected reaction monitoring (SRM) mode. To test the performance of this method, residual levels of E1, E2 and E3 were measured in the muscle tissue of juvenile eels subjected to feminization treatment with E2.
  
  
  RESULTS
  We report that following 17β-estradiol treatment, E2 is rapidly metabolized from the eel tissue, with a 50% depletion rate per day. Five days post-treatment, E2 returned to the level found in non-treated controls, similar to levels found in wild mature female eels.
  
  
  CONCLUSIONS
  The method presented herein allows the quantitative analysis of E1, E2 and E3 in fish tissue samples. Under the experimental conditions, E2 in fish tissue samples returned to physiological levels post hormonal treatment. Copyright © 2017 John Wiley & Sons, Ltd.
authors.affiliation: Proteomics and Mass Spectrometry Core Facility, Faculty of Medicine, Dalhousie University, 5850 College Street, Halifax, Nova Scotia, Canada, B3H 4R2.
authors.forename: Alejandro
authors.identifier: http://orcid.org/0000-0001-8646-8525
authors.initials: A
authors.lastname: Cohen
authors.affiliation: NovaEel Inc., 2161 Armcrescent E Dr., Halifax, Nova Scotia, Canada, B3H 4R2.|Department of Biology, Dalhousie University, 1355 Oxford St., Halifax, Nova Scotia, Canada, B3H 4R2.
authors.forename: Neil W
authors.initials: NW
authors.lastname: Ross
authors.affiliation: NovaEel Inc., 2161 Armcrescent E Dr., Halifax, Nova Scotia, Canada, B3H 4R2.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Smith
authors.affiliation: Proteomics and Mass Spectrometry Core Facility, Faculty of Medicine, Dalhousie University, 5850 College Street, Halifax, Nova Scotia, Canada, B3H 4R2.|Department of Pharmacology, Faculty of Medicine, Dalhousie University, 5850 College Street, Halifax, Nova Scotia, Canada, B3H 4R2.|Department of Surgery, Faculty of Medicine, Dalhousie University, 5850 College Street, Halifax, Nova Scotia, Canada, B3H 4R2.
authors.forename: James P
authors.initials: JP
authors.lastname: Fawcett
mesh_terms: D000811:Anguilla; D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods*; D004350:Drug Residues / Q000032:analysis*; D004958:Estradiol / Q000032:analysis*; D004964:Estriol / Q000032:analysis*; D004970:Estrone / Q000032:analysis*; D005260:Female; D005396:Fish Products / Q000032:analysis; D057230:Limit of Detection; D018482:Muscle, Skeletal / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry
chemical_list: D004970:Estrone; D004958:Estradiol; D004964:Estriol