| A new method was established for the simultaneous determination of 10 quinolone(QN) residues in animal-originated foodstuffs by ultrafiltration tube cleaning with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS).After extraction with acetonitrile (containing 1%acetic acid),the extract was purified with 50 mL Millipore ultrafiltration tube (Molecular Weight Cut-Off，MWCO:3 kD),and then the centrifugal liquid was evaporated to dryness under a stream of nitrogen,and redissolved.The analytes were separated on a Waters Xbridge C18 column using 0.1%formic acid-acetonitrile as mobile phase.The identification and quantification of 10 quinolone residues were carried out under positive electrospray ionization (ESI+) in multiple reaction monitoring (MRM) mode，the quantification analysis was performed by the external standard method.The calibration curves showed good linearities in the range of 5.0-100 μg/kg for all QNs.The limits of detection for all QNs were in the range of 0.15-0.75 μg/kg,and the limits of quantitation were 0.49-2.59 μg/kg.The recoveries of these analytes varied from 71.4%to 85.9%at spiked levels of 5.0,10,50 μg/kg,with relative standard deviations of 3.9%-10.7%.This method was simple,rapid,sensitive and reproducible,and could be applied in the determination of 10 quinolone residues in anima-originated foodstuffs． |