Simultaneous detection of five coccidiostats in eggs by liquid chromatography-tandem mass spectrometry

A relatively fast, simple and very selective liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the detection of diclazuril, dimetridazole, halofuginone, nicarbazin and robenidine in eggs has been developed and validated. After a simple extraction with acetonitrile and evaporation of the organic phase, the extract was filtered and directly injected into the LC-MS-MS system on a C-18 column. The parent ions were selected for further fragmentation with argon. The developed method was validated according to Revision of Commission Decision 93/256/EC [EC, Final version of Commission Decision laying down analytical methods to be used for detecting substances and residues thereof in live animals and animal products according to Council Directive 96/23/EC (Revision of Commission Decision 93/256/EC)]. The validation parameters linearity, precision, recovery, specificity, decision limit (CCalpha) and detection capability (CCbeta) were determined. CCalpha varied from 0.75 mug kg(-1) for dimetridazole to 6 mug kg(-1) for diclazuril and CCbeta varied from 0.9 mug kg(-1) for dimetridazole up to 8.3 mug kg(-1) for diclazuril. (C) 2002 Elsevier Science B.V. All rights reserved.