title: Development and validation of a confirmatory method for the determination of 12 non steroidal anti-inflammatory drugs in milk using liquid chromatography-tandem mass spectrometry.
abstract: A rapid and reliable LC-MS/MS method for the simultaneous confirmation of twelve non steroidal anti-inflammatory drugs (NSAIDs) in bovine milk was developed and fully validated in accordance with the European Commission Decision 2002/657/EC. The validation scheme was built in accordance with the MRLs or target analytical levels (EU-CRL recommended concentrations and detection capabilities) of the analytes, except for diclofenac for which the lower level of validation achieved was 0.5 μg kg(-1) whereas its MRL is 0.1 μg kg(-1). The NSAIDs investigated were as follows: phenylbutazone (PBZ), oxyphenylbutazone (OPB), naproxen (NP), mefenamic acid (MF), vedaprofen (VDP), flunixin (FLU), 5-hydroxyflunixin (FLU-OH), tolfenamic acid (TLF), meloxicam (MLX), diclofenac (DC), carprofen (CPF) and ketoprofen (KTP). Several extraction procedures had been investigated during the development phase. Finally, the best results were obtained with a procedure using only methanol as the extraction solvent, with an evaporation step included and no further purification. Chromatographic separation was achieved on a C18 analytical column and the run was split in 2 segments. Matrix effects were also investigated. Data acquisition implemented for the confirmatory purpose was performed by monitoring 2 MRM transitions per analyte under the negative electrospray mode. Mean relative recoveries ranged from 94.7% to 110.0%, with their coefficients of variation lying between 2.9% and 14.7%. Analytical limits expressed in terms of decision limits (CCα) were evaluated between 0.69 μg kg(-1) (FLU) and 27.54 μg kg(-1) (VDP) for non-MRL compounds, and at 0.10 (DC), 15.37 (MLX), 45.08 (FLU-OH), and 62.96 μg kg(-1) (TLF) for MRL compounds. The validation results proved that the method is suitable for the screening and confirmatory steps as implemented for the French monitoring plan for NSAID residue control in bovine milk.
authors.affiliation: Veterinary Drug Residues Unit, Laboratory of Fougeres, ANSES (National Agency for Food, Environment and Occupational Health Safety), BP 90203, La Haute Marche, 35133 Javené, France. estelle.dubreil@anses.fr
authors.forename: Estelle
authors.initials: E
authors.lastname: Dubreil-Chéneau
authors.forename: Yvette
authors.initials: Y
authors.lastname: Pirotais
authors.forename: Mélaine
authors.initials: M
authors.lastname: Bessiral
authors.forename: Brigitte
authors.initials: B
authors.lastname: Roudaut
authors.forename: Eric
authors.initials: E
authors.lastname: Verdon
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000032:analysis* / Q000302:isolation & purification; D002417:Cattle; D002853:Chromatography, Liquid / Q000379:methods*; D004350:Drug Residues / Q000032:analysis*; D005260:Female; D006041:Goats; D006851:Hydrochloric Acid; D000432:Methanol; D008892:Milk / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D006851:Hydrochloric Acid; D000432:Methanol