New Reagent for Trace Determination of Protein-Bound Metabolites of Nitrofurans in Shrimp Using Liquid Chromatography with Diode Array Detector

摘要

The synthesis of derivatives of metabolites from furazolidone,furaltadone,nitrofurazone,and nitrofurantoin using a new derivatizing reagent,2-naphthaldehyde(NTA),is described.The reaction product was used in liquid chromatography with diode array detector(LC-DAD)for determination of protein-bound metabolites of nitrofurans in shrimp followed by two steps of liquid-liquid extraction.Derivatives of nitrofuran metabolites are well separated from NTA remaining in the extract upon separation on a ChromSpher 5 Pesticide(250 x 4.6 mm,5 mu m)column at 40 deg C with acetonitrile/5 mM ammonium acetate adjusted to pH 7.5 gradient as the mobile phase and DAD detection at 308 nm except for naphthyl derivative of 1-aminohydantoin at 310 nm.The high absorptivity of these derivatives makes simultaneous screening of these metabolites in shrimp at 1 mu g/kg possible for the first time using LC-DAD.The method was validated using blank shrimp fortified with all four metabolites at 1,1.5,and 2 mu g/kg.Recoveries were >86% with relative standard deviations of <14% for all four metabolites.Comparison between LC-DAD and APCI-MS/MS shows very good agreement for shrimp samples.