title: Detection of synthetic glucocorticoid residues in cattle tissue and hair samples after a single dose administration using LC-MS/MS.
abstract: A sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for the detection of several synthetic glucocorticoids in kidney, muscle and hair samples of cattle after a single intramuscular injection is described. After a dichloromethane wash of the hair samples, analytes were released from the hair matrix by enzymatic digestion. Muscle samples were also digested enzymatically using proteinase, while kidney samples were deconjugated by Helix pomatia juice. These preliminary steps were followed by a methanol extraction and a solid phase extraction (SPE) clean up step for all matrices. Chromatographic separation was achieved on a Hypersil Hypercarb column and MS/MS data were obtained in the multiple reaction monitoring mode using negative electrospray ionization. The developed protocols were evaluated by assessing residue concentrations in muscle, kidney and hair samples of thirteen calves, treated with a particular intramuscular injection of glucocorticoid. The lowest residue levels were found in muscle samples (approximately 5% of the residue levels in kidney), while high residue levels were obtained in hair samples. Hair is an interesting matrix since the sampling is non-invasive and the drugs may stay incorporated for a longer period of time.
authors.affiliation: Laboratory of Food Analysis, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium. olivia.vandenhauwe@Ugent.be
authors.forename: Olivia
authors.initials: O
authors.lastname: Van den hauwe
authors.forename: Frederic
authors.initials: F
authors.lastname: Dumoulin
authors.forename: Chris
authors.initials: C
authors.lastname: Elliott
authors.forename: Carlos
authors.initials: C
authors.lastname: Van Peteghem
mesh_terms: D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004350:Drug Residues / Q000032:analysis*; D005938:Glucocorticoids / Q000008:administration & dosage / Q000032:analysis*; D006197:Hair / Q000737:chemistry*; D012015:Reference Standards; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D005938:Glucocorticoids