Quick determination of fipronil and its metabolites in eggs by gas chromatography-triple quadrupole mass spectrometry

A method was established for the simultaneous determination of fipronil and its metabolites in eggs by gas chromatography-tandem mass spectrometry coupled with QuECh-ERS. Fipronil and its metabolites were extracted from eggs with acetonitrile, and the solution was dehydrated with 150 mg anhydrous magnesium sulfate. The extracts were purified with 50 mg N-propyl ethylenediamine ( PSA ) and 50 mg C18, and a capillary column pesticide II was used. The analytes were detected in timed selected reaction monitoring ( timed-SRM ) mode, and were quantified using external standard method with matrix correction standard curves. A good linearity in the range of 1.0 - 200 mu g/L with correlation coefficients ( R-2 ) > 0.999 was observed. The limits of quantification ( LOQs ) were between 0.5 and 1.0 mu g/kg. The recoveries at three spiked levels ( 2. 0, 5.0 and 10.0 mu g/kg ) were in the range of 87.8% to 111.5% with RSDs between 2.0% and 9. 2% ( n=3 ). This new method satisfied the related regulations of the European Union for the determination of fipronil and its metabolites in eggs.