文摘
This research described a sensitive and rapid UPLC-MS/MS method for the determination of mequindox and its six major metabolites in chicken muscle, chicken liver, swine muscle, and swine liver. Among the metabolites, carbonyl reduction-1,4-bisdesoxy-mequindox is novel. Target analytes could be extracted by ethyl acetate without any acidolysis or enzymolysis steps. After purification by a Bond Elut C18 cartridge, analysis was carried out by UPLC-MS/MS using positive ion multiple reaction monitoring (MRM) mode. Validation was performed in spiked samples, and mean recoveries ranged from 64.3 to 114.4%, with intraday and interday variations of less than 14.7 and 19.2%, respectively. The limit of detection (LOD) was <1.0 μg kg–1, whereas the limit of quantification (LOQ) was <4.0 μg kg–1. This procedure will help monitor mequindox residues in animal-derived food, and it will also facilitate further pharmacokinetics of mequindox.