title: Confirmation and quantification of clenbuterol in horse urine using liquid chromatography tandem mass spectrometry triple quadrupole.
abstract: Clenbuterol (CLE) is used in horses as a bronchodilator and for its anabolic steroid-like effects. CLE is a Class 3 drug according to current Association of Racing Commissioners International (ARCI) Uniform Classification Guidelines. The Racing Medication and Testing Consortium recommended a urine CLE threshold of 140 pg/mL after careful scientific review of the results of studies describing the disposition of CLE in the horse and this threshold was adopted by the ARCI. Enzyme-linked immunosorbent assay was previously used to screen samples for CLE in Illinois, but could not detect such low concentrations in urine. Thus, a liquid-liquid extraction of CLE from urine followed by quantification by liquid chromatography-tandem mass spectrometry was developed and validated. Method validation included testing stability, ion suppression and enhancement, precision, accuracy and uncertainty. Intra-, interday and total precision and accuracy were calculated for each control and found to be within the ±15% acceptance range. The Guide to the Expression of Uncertainty in Measurement approach was used to calculate uncertainty, which was 11% at the 95% confidence level. In the past 5 years, only 15 samples were reported as positive for CLE in Illinois. This new method was used in a pilot program to screen and confirm samples received from thoroughbred and harness horses.
authors.affiliation: Animal Forensic Toxicology Laboratory, Department of Biopharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 2242 West Harrison Street, Chicago, IL 60612, USA jenibishop@ymail.com.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Bishop
authors.affiliation: Animal Forensic Toxicology Laboratory, Department of Biopharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 2242 West Harrison Street, Chicago, IL 60612, USA.
authors.forename: Brendan
authors.initials: B
authors.lastname: Heffron
authors.affiliation: Animal Forensic Toxicology Laboratory, Department of Biopharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 2242 West Harrison Street, Chicago, IL 60612, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Taddei
authors.affiliation: Animal Forensic Toxicology Laboratory, Department of Biopharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 2242 West Harrison Street, Chicago, IL 60612, USA.
authors.forename: Marc
authors.initials: M
authors.lastname: Benoit
authors.affiliation: Animal Forensic Toxicology Laboratory, Department of Biopharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 2242 West Harrison Street, Chicago, IL 60612, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Hurt
authors.affiliation: Animal Forensic Toxicology Laboratory, Department of Biopharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 2242 West Harrison Street, Chicago, IL 60612, USA.
authors.forename: Sara
authors.initials: S
authors.lastname: Costello
authors.affiliation: Animal Forensic Toxicology Laboratory, Department of Biopharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 2242 West Harrison Street, Chicago, IL 60612, USA.
authors.forename: Melissa
authors.initials: M
authors.lastname: Gross
authors.affiliation: Animal Forensic Toxicology Laboratory, Department of Biopharmaceutical Sciences, College of Pharmacy, University of Illinois at Chicago, 2242 West Harrison Street, Chicago, IL 60612, USA.
authors.forename: Adam
authors.initials: A
authors.lastname: Negrusz
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods*; D002976:Clenbuterol / Q000652:urine*; D006736:Horses; D059625:Liquid-Liquid Extraction; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D002976:Clenbuterol