title: Optimisation and validation of a quantitative and confirmatory LC-MS method for multi-residue analyses of β-lactam and tetracycline antibiotics in bovine muscle.
abstract: A multi-residue method for the determination of the β-lactam antibiotics ampicillin, cefazolin, cloxacillin, dicloxacillin, nafcillin, oxacillin, penicillin G, penicillin V and the tetracyclines chlotetracycline, tetracycline and oxytetracycline was optimised and validated in bovine muscle. The method is based on the extraction of the residues from muscle using water/acetonitrile (2/8, v/v) with subsequent use of dispersive solid-phase C18 and hexane for purification. Extracts were analysed using ultra-performance liquid chromatography (UPLC-MS/MS) coupled with the mass spectrometer in positive electrospray ionisation mode (ESI+) for all analytes. The method was validated according to the requirements of European Commission Decision 2002/657/EC. The validation results were obtained within the MRL range of 0-1.5 of the MRL, with recoveries varying from 90% to 110% and CV < 20% (n = 54), except for cloxacillin, dicloxacillin and nafcillin. However, matrix interference was observed. The decision limit (CCα) ranged from 10% to 15% of the MRL. The uncertainty measurement was estimated based on both bottom-up and top-down strategies and the uncertainty values were found to be lower than 20% of the MRL. The method has a simple extraction procedure whereby analytes are separated with reasonable resolutions in a single 11-min chromatographic run. According to the validation results, this method is suitable for monitoring β-lactams and tetracyclines according to National Program for Residue and Contaminant Control - Brazil (NPRC-Brazil) in bovine muscle.
authors: Ministry of Agriculture, Livestock and Food Supply, MAPA, National Agricultural Laboratory, LANAGRO/MG, Brazil. cristiana.rezende@agricultura.gov.br
authors: C P
authors: CP
authors: Rezende
authors: M P
authors: MP
authors: Almeida
authors: R B
authors: RB
authors: Brito
authors: C K
authors: CK
authors: Nonaka
authors: M O
authors: MO
authors: Leite
mesh_terms: D000818:Animals; D001938:Brazil; D002417:Cattle; D002853:Chromatography, Liquid / Q000379:methods*; D004350:Drug Residues / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis* / Q000517:prevention & control; D057230:Limit of Detection; D008460:Meat / Q000032:analysis*; D009132:Muscles / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013752:Tetracycline / Q000032:analysis*; D019155:Veterinary Drugs / Q000032:analysis; D047090:beta-Lactams / Q000032:analysis*
chemical_list: D019155:Veterinary Drugs; D047090:beta-Lactams; D013752:Tetracycline