Abstract: A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was established for the determination of inabenfide in fruits, vegetables, tea, honey, cereals and animal-derived foods. The food samples were extracted with acetonitrile, then purified by dispersion solid phase extraction using primary secondary amine (PSA) and C18 as solid phase. The residue was determined and confirmed by HPLC-MS/MS and quantified by external standard method. The mass spectrometric detection was operated with electrospray in positive ionization mode and inabenfide was identified in multiple reaction monitoring (MRM) mode. The interference of matrix was reduced by the matrix-matched calibration standard curves. The linear range of the method was 1-100 μg/kg, with the correlation coefficients (r2) of 0.998-0.999. The recoveries of inabenfide spiked in food samples were 85.2%-112.4% at the spiked levels of 5, 10, 50 μg/kg. The relative standard deviations (RSDs) were less than 8.5%. The limits of detection (LODs) were 0.08-1.64 μg/kg, and the limits of quantification (LOQs) were 0.30-5.48 μg/kg. The results showed that the proposed method is sensitive and accurate for the determination of inabenfide in foodstuffs.

Key words: foodstuffs, inabenfide, residue, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS)