title: Development and validation of a hydrophilic interaction liquid chromatography with tandem mass spectrometry method for the simultaneous detection and quantification of etilefrine and oxilofrine in equine blood plasma and urine.
abstract: A sensitive hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry method was developed and validated for the simultaneous detection and quantification of etilefrine and oxilofrine in equine blood plasma and urine. The method is highly sensitive and specific with good precision and accuracy. In plasma the limit of detection and limit of quantification are 0.03 and 0.1 ng/mL, respectively, for both analytes. In urine the limit of detection and limit of quantification are 0.3 and 1 ng/mL, respectively, for both analytes. The suitability of the method for doping control analysis in equine species is demonstrated by analyzing postadministration samples collected after a single intravenous administration of 50 mg etilefrine to a standardbred mare. Etilefrine was detected up to 120 h in urine and up to 48 h in plasma. Etilefrine is highly conjugated in equine urine whereas it exists in the free form in equine plasma. Therefore, enzyme hydrolysis prior to sample preparation is recommended for the detection and quantification of etilefrine and oxilofrine in equine urine.
authors.affiliation: Maxxam Analytics, Burnaby, BC, Canada.
authors.forename: Noel
authors.initials: N
authors.lastname: Kong
authors.forename: Rong
authors.initials: R
authors.lastname: Yi
authors.forename: Sarah
authors.initials: S
authors.lastname: Zhao
authors.forename: Jasmeet
authors.initials: J
authors.lastname: Sandhu
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Lam
authors.forename: Devan
authors.initials: D
authors.lastname: Loganathan
authors.forename: Barbara
authors.initials: B
authors.lastname: Morrissey
mesh_terms: D000818:Animals; D002316:Cardiotonic Agents / Q000097:blood* / Q000652:urine*; D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation / Q000379:methods*; D004300:Doping in Sports; D004809:Ephedrine / Q000031:analogs & derivatives* / Q000097:blood / Q000652:urine; D005039:Etilefrine / Q000097:blood* / Q000652:urine*; D006736:Horses; D053719:Tandem Mass Spectrometry / Q000379:methods* / Q000662:veterinary
chemical_list: D002316:Cardiotonic Agents; C026055:oxilofrine; D004809:Ephedrine; D005039:Etilefrine
keywords: Equine; Etilefrine; Hydrophilic interaction liquid chromatography; Oxilofrine; Tandem mass spectrometry