Multiclass method for the determination of 62 antibiotics in milk

Abstract

A multiclass method for screening and confirmatory analysis of antimicrobial residues in milk has been developed and validated. Sixty-two antibiotics belonging to ten different drug families (amphenicols, cephalosporins, lincosamides, macrolides, penicillin, pleuromutilins, quinolones, rifamycins, sulfonamides and tetracyclines) have been included. After the addition of an aqueous solution of EDTA, the milk samples were extracted twice with acetonitrile, evaporated and dissolved in ammonium acetate. After centrifugation, 10 µl were analysed using LC-Q-Orbitrap operating in positive electrospray ionization mode. The method was validated in bovine milk in the range 2-150 µg kg(-1) for all antibiotics; for four compounds with maximum residue limits higher than 100 µg kg(-1) , the validation interval has been extended until 333 µg kg(-1) . The estimated performance characteristics were satisfactory complying with the requirements of Commission Decision 2002/657/EC. Good accuracies were obtained also taking advantage from the versatility of the hybrid mass analyser. Identification criteria were achieved verifying the mass accuracy and ion ratio of two ions, including the pseudomolecular one, where possible. Finally, the developed procedure was applied to 13 real cases of suspect milk samples (microbiological assay) confirming the presence of one or more antibiotics, although frequently, the maximum residue limits were not exceeded. The availability of rapid multiclass confirmatory methods can avoid wastes of suspect, but compliant, raw milk samples. Copyright © 2016 John Wiley& Sons, Ltd.

Distribution of Transferable Antibiotic Resistance Genes in Laboratory-Reared Edible Mealworms (Tenebrio molitor L.)

“…The analysis of the 64 antibiotics listed in Table 2 , which belong to ten drug families (amphenicols, beta-lactams, diamino-pyrimidines, lincosamides, macrolides, pleuromutilins, quinolones, rifamycins, sulfonamides and tetracyclines), was carried out in wheatmeal and pooled carrots as described by Moretti et al ( 2016 ) with some modifications regarding the sample preparation protocol of the wheatmeal. Briefly, 2 g of organic wheatmeal was sequentially extracted using acetonitrile/water 50/50 (v/v), acetonitrile containing formic acid at 0.1%, and an aqueous solution of 0.1 M Na 2 EDTA.…”

Multiclass and multiresidue screening of veterinary drugs and pesticides in infant formula using Quadrupole‐Orbitrap MS with PRM scan mode

“…Great emphasis has been placed on risk discovery, and screening methodology characterizing high‐throughput capability, therefore, is preferred. In this context, simultaneous multiclass and multiresidue analysis is a better choice and attracts more and more attention, especially with advances of mass spectrometry . In present study, the compounds from 11 different chemical classes (antivirals, anticoccidials, macrolides, pyrethroids, insecticides, sulfonamides, beta‐agonists, sedatives, thyreostats, nonsteroidal anti‐inflammatory drugs, and other pharmacologically active substances), which are commonly relevant to dairy products as regulated in China and EU, were selected as target analytes to be investigated for developing an efficient mass spectrometry‐based screening method.…”

Transfer of a Multiclass Method for over 60 Antibiotics in Food from High Resolution to Low Resolution Mass Spectrometry

“…About three years later, the same Laboratory of Zurich, and the research group of Almeria University developed multiclass procedures for veterinary drugs, respectively, in meat, and milk, using LC-Orbitrap technique, a new MS analyzer, that was commercialized in 2005 [13,29]. Later, the introduction of benchtop hybrid high-resolution mass spectrometers (mainly, Q-TOF and Q-Orbitrap) produced further advantages in terms of selectivity and accuracy and, accordingly, these kinds of equipment has been more commonly applied (Table 1) [14,15,18,21,22,24,25,26,28,29].…”

“…The possibility of easy implementation and sustainable daily management, independent from the available LC-MS equipment. The aim of this work was to discuss the transfer of previously developed multiclass methods for more than sixty antibiotics in meat and milk from an LC-Q-Orbitrap platform to an LC-QqQ one [24,25]. The performance characteristics of the new LC-QqQ methods were estimated by means of full validation studies carried out according to European Commission Decision 2002/657/EC [30].…”