Enantioselective determination of acaricide etoxazole in orange pulp, peel, and whole orange by chiral liquid chromatography with tandem mass spectrometry. Issue 4 (February 2015)

• Record Type: Journal Article
• Authors: Yao, Zhoulin; Li, Zuguang; Zhuang, Shulin; Li, Xiaoge; Xu, Mingfei; Lin, Mei; Wang, Qiang; Zhang, Hu
• Is Part Of: Journal of separation science. Volume 38:Issue 4(2015:Feb.)
• Page Start: 599
• Page End: 604
• Publication Date: 2015-02
• Subjects: Separation (Technology) -- Periodicals; Chromatographic analysis -- Periodicals; 543.089
• DOI: 10.1002/jssc.201401065
• Languages: English
• ISSNs: 1615-9306

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>An efficient enantioselective method for the determination of etoxazole in orange pulp, peel, and whole orange was developed using liquid chromatography with tandem mass spectrometry. The enantioseparation was performed on a Chiralpak AD‐3R column at 30ºC using acetonitrile with 0.1% formic acid solution (80:20, v/v) as the mobile phase in less than 5 min. Quantification was achieved using matrix‐matched standard calibration curves. The overall mean recoveries for two enantiomers from orange pulp and whole orange were 91.0–99.6% and the orange peel was 92.6–103.1%, with relative standard deviations of 0.8–5.4% intraday and 2.0–4.8% interday at 1, 10, and 100 μg/kg levels, and 1.3–5.2% intraday and 3.5–4.3% interday at 5, 50, and 500 μg/kg levels, respectively. The limits of quantification for all enantiomers in three matrices did not exceed 5 μg/kg. Moreover, the absolute configuration of etoxazole enantiomers had been determined by the combination of experimental and predicted electronic circular dichroism spectra, and the first eluted enantiomer was confirmed as (<italic>S</italic>)‐etoxazole on a Chiralpak AD‐3R column while (<italic>R</italic>)‐etoxazole was first on three cellulose chiral columns. The application of the proposed method to real sample analysis suggests its potential use in enantioselective determination of etoxazole enantiomers in citrus.</p> </abstract>