title: Maximum residue level validation of triclabendazole marker residues in bovine liver, muscle and milk matrices by ultra high pressure liquid chromatography tandem mass spectrometry.
abstract: Triclabendazole is the only anthelmintic drug, which is active against immature, mature and adult stages of fluke. The objective of this work was to develop an analytical method to quantify and confirm the presence of triclabendazole residues around the MRL. In this work, a new analytical method was developed, which extended dynamic range to 1-100 and 5-1000 μg kg(-1) for milk and tissue, respectively. This was achieved using a mobile phase containing trifluoroacetic acid (pK(a) of 0.3), which resulted in the formation of the protonated pseudomolecular ions, [M+H](+), of triclabendazole metabolites. Insufficient ionisation of common mobile phase additives due to low pK(a) values (<2) was identified as the cause of poor linearity. The new mobile phase conditions allowed the analysis of triclabendazole residues in liver, muscle and milk encompassing their EU maximum residue levels (MRL) (250, 225 and 10 μg kg(-1) respectively). Triclabendazole residues were extracted using a modified QuEChERS method and analysed by positive electrospray ionisation mass spectrometry with all analytes eluted by 2.23 min. The method was validated at the MRL according to Commission Decision (CD) 2002/657/EC criteria. The decision limit (CCα) of the method was in the range of 250.8-287.2, 2554.9-290.8 and 10.9-12.1 μg kg(-1) for liver, muscle and milk, respectively. The performance of the method was successfully verified for triclabendazole in muscle by participating in a proficiency study, the method was also applied to incurred liver, muscle and milk samples.
authors.affiliation: Food Safety Department, Teagasc, Ashtown Food Research Centre, Ashtown, Dublin 15, Ireland. michelle.whelan@agriculture.gov.ie
authors.forename: Michelle
authors.initials: M
authors.lastname: Whelan
authors.forename: John
authors.initials: J
authors.lastname: O'Mahony
authors.forename: Mary
authors.initials: M
authors.lastname: Moloney
authors.forename: Kevin M
authors.initials: KM
authors.lastname: Cooper
authors.forename: Ambrose
authors.initials: A
authors.lastname: Furey
authors.forename: D Glenn
authors.initials: DG
authors.lastname: Kennedy
authors.forename: Martin
authors.initials: M
authors.lastname: Danaher
mesh_terms: D000818:Animals; D001562:Benzimidazoles / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004350:Drug Residues / Q000032:analysis; D057230:Limit of Detection; D008099:Liver / Q000737:chemistry*; D008892:Milk / Q000737:chemistry*; D009132:Muscles / Q000737:chemistry*; D015203:Reproducibility of Results; D053719:Tandem Mass Spectrometry / Q000379:methods*; D000077682:Triclabendazole
chemical_list: D001562:Benzimidazoles; D000077682:Triclabendazole