Development of an ASE-GC-MS/MS method for detecting dinitolmide and its metabolite 3-ANOT in eggs

An accelerated solvent extraction coupled with gas chromatography-tandem mass spectrometry (ASE-GC-MS/MS) method for detecting dinitolmide residue and its metabolite (3-amino-2-methyl-5-nitrobenzamide, 3-ANOT) in eggs was developed and optimized. The samples were extracted using ASE with acetonitrile as the extractant and were purified by passage through a neutral alumina solid-phase extraction column. Then, the samples were analyzed using the GC-MS/MS method. The optimized method parameters were validated according to the requirements set forth by the European Union and the Food and Drug Administration. The average recoveries of dinitolmide and 3-ANOT from eggs (egg white, egg yolk, and whole egg) at the limit of quantification (LOQ), 0.5 maximum residue limit (MRL), 1 MRL, and 2 MRL were 82.74% to 87.49%, the relative standard deviations (RSDs) were less than 4.63%, and the intra-day RSDs and the inter-day RSDs were 2.96% to 5.21% and 3.94% to 6.34%, respectively. The limits of detection and the LOQ were 0.8 to 2.8 μg/kg and 3.0 to 10.0 μg/kg, respectively. The decision limits (CC_α ) were 3001.69 to 3006.48 μg/kg, and the detection capabilities (CC_β ) were 3001.74 to 3005.22 μg/kg. Finally, the new method was successfully applied to the quantitative determination of dinitolmide and 3-ANOT in 50 commercial eggs from local supermarkets.