[Determination of Sudan Red I-IV in duck egg yolk using ultra performance liquid chromatography-tandem mass spectrometry]

A method of the simultaneous analysis of Sudan Red I - IV in duck egg yolk was developed with an ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Acetonitrile was used to extract the residues from duck egg yolk, and water was added into the extract to precipitate impurities such as protein and fat. The supernatant was detected by the UPLC-MS/MS after refrigeration and centrifugation. The sample was separated on a Waters Acquity BHE C18 column, and detected by MS/MS with the multiple reaction monitoring (MRM) mode. The limits of detection (LOD) were 0.05 microg/L in the standard solution, and 10 microg/kg of the four substances in the sample spiked with Sudan Red I - IV. The average recoveries were between 50.2% - 101.3% at three spiking levels of 100.0, 200.0, 300.0 microg/kg. The experiment results show that this method is of high sensitivity, low LOD, better determination capacity and shorter analysis time. The method could meet the high-throughout detection of Sudan Red in food samples.