Determination of marker residue of Olaquindox in fish tissue by ultra performance liquid chromatography–tandem mass spectrometry

✍ Scribed by Xiaojun Zhang; Bin Zheng; Hong Zhang; Xuechang Chen; Guangming Mei

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 252 KB
• Volume: 34
• Category: Article
• ISSN: 1615-9306
• DOI: 10.1002/jssc.201000722

✦ Synopsis

Abstract

Methyl‐3‐quinoxaline‐2‐carboxylic acid (MQCA) is the last major remaining detectable metabolite of Olaquindox in animal tissue. A rapid, sensitive and specific ultra performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method was developed for the detection and quantification of MQCA in fish tissue using deuterated quinoxaline‐2‐carboxylic acid (d~4~‐QCA) as internal standard. Various parameters affecting sample preparation, LC separation and MS/MS detection were investigated, and the optimal conditions concerned were determined. Fish tissue samples were subject to hydrochloric acid hydrolysis followed by Oasis MAX solid‐phase extraction clean‐up; analysis was performed using UPLC coupled to electrospray MS/MS. The chromatographic separation was achieved in less than 5 min. The limit of detection and the limit of quantification were 0.1 and 0.25 ng/g, respectively. The average recoveries of MQCA, spiked at levels of 0.25–50.0 ng/g, were from 92.7 to 104.3%. The relative standard deviation values were <6%. The validated method was successfully applied to analyze 60 batch samples collected from the local market.