Analysis of nitrofuran metabolic residues in salt by liquid chromatography-tandem mass spectrometry

Recent reports from the Brazilian Agricultural Ministry program of residue control describe some cases of the presence of semicarbazide, the target metabolite of nitrofurazone {2-[(5-nitro-2-furanyl)methylene]-hydrazinecarboxamide}, in samples of salted chicken meat. Since that contamination can be originated from other reasons in addition to nitrofurazone abuse, our laboratory has developed a sensitive and simple method for detection of four nitrofuran metabolites in salt samples. This method include a previous hexane extraction of the metabolites followed by a derivatization reaction with 2-nitrobenzaldehyde. The nitrophenyl derivatives were analyzed by liquid chromatography-tandem mass spectrometry without any additional clean-up procedures. The limit of quantification for routine analysis was 0.5 mug kg(-1) for each metabolite. (C) 2004 Elsevier B.V. All rights reserved.