Simultaneous determination of thirty non-steroidal anti-inflammatory drug residues in swine muscle by ultra-high-performance liquid chromatography with tandem mass spectrometry

An ultra-high-performance liquid chromatography with tandem mass spectrometric detection (UHPLC–MS/MS) method was established for the simultaneous determination of residues of thirty non-steroidal anti-inflammatory drugs (NSAIDs) in swine muscle. The samples were extracted with acetonitrile and phosphoric acid. The extracts were defatted with n-hexane, and then purified by HLB solid-phase extraction cartridge. Analysis was carried out on UHPLC–ESI-MS/MS working with multiple reaction monitoring mode with polarity switching. Limits of detection were between 0.4 μg/kg and 2.0 μg/kg, and limits of quantification were between 1.0 μg/kg and 5.0 μg/kg. The recoveries of NSAIDs were between 61.7% and 125.7% at spiked levels of 1.0–500 μg/kg. The repeatability was less than 8% and the within-laboratory reproducibility was not more than 12.3%. The method was reliable, convenient and sensitive.