Simultaneous Determination of Nitrofuran Metabolite Residues in Different Animal Derived Foods by UPLC-MS/MS

Ultra-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the measurement of four metabolites of nitrofuran antibiotics in 4 animal derived foods (porcine muscle, pork liver, crab and shrimp). Samples pretreatment and UPLC-MS/MS conditions were optimized. The samples were hydrolyzed by hydrochloric acid, derivatized by 2-nitrobenzaldehyde, extracted by ethyl acetate, scanned by ESI positive mode and determined by MRM. The results showed that the method had a good linearity within the dynamic range of 1~100 ng/mL. The average recoveries were 84.6%~118.1%, and the relative standard deviations (RSD) were 2.9%~8.1%. The limit of detection (LOD) for 3-amino-2-oxazolidinone (AOZ), semicarbazide (SEM), 5-morpholino-3-amino-2-oxazolidone (AMOZ) and 1-amino-hydantoin (AHD) were 0.1, 0.2, 0.2 and 0.5 μg/kg, respectively. The limit of quantification (LOQ) for 3-amino-2-oxazolidinone (AOZ), semicarbazide (SEM), 5-morpholino-3-amino-2-oxazolidone (AMOZ), and 1-amino-hydantoin (AHD) were 0.4, 0.5, 0.5 and 1.0 μg/kg, respectively, which met the requirements of national standards. The proposed method was used to detect nitrofuran residual in 80 animal derived food samples and quality control samples. The results were close to that detected by national standard method GB/T 20752-2006. The proposed method was time saving and cost-efficient. The results could provide theoretical basis and reference for the detection of nitrofuran residual in animal derived food.