High-performance Liquid Chromatography-tandem Mass Spectrometry for Determination of the Metabolites of Nitrofurans Residues in Eriocheir Sinensis

A high-performance liquid chromatography-tandem mass spectrometric method is established for the determination of metabolites of nitrofurans residues in Chinese Mitten Crab.Homogenized edible samples are hydrolyzed and derivatized using 2-nitrobenzaldehyde at 37℃ overnight followed by addition of internal standards.After adjusting the pH to 7.0~7.4,the solution is extracted twice by ethyl acetate.The residue is dissolved with 1.0mL dissolvant solution(acetontrile:0.4% acetic acid solution=10:90) and defatted with n-hexane(saturated by acetonitrile).The four analytes are separated on ZORBAX Eclipse XDB-C18 Column,and finally identified by Electrospray ionization-tandem mass spectrometry(ESI-MS-MS)analysis.Analytic confirmation is performed using multi-reaction monitoring(MRM) with one precursor ion and two product ions as identifiers.Analytes quantification is performed using internal standard method.The quantitative limit of the method is 0.5 μg.kg-1.and the linear range is 0.25~10.0μg.kg-1.The recovery range of AMOZ is 92.8%~106%,SEM is 84.5%~94.6%,AHD is 80.6%~98.6%,AOZ is 88.4%~105%,when fortified at the concentration of 0.5 μg.kg-1,1 μg.kg-1,2 μg.kg-1 and 10.0 μg.kg-1.The RSD of the method is less than 10%.