The Research On Determination Of Quinolones Residues In Chicken By UPLC-MS/MS Coupled With MISPE

The quinolones are widely used in veterinary clinic field for the prevention and treatment of the animal diseases because of their broad antibacterial spectrum,strong bactericidal effect and less side effects.However,its overuse and irrational use are becoming more and more serious,leading to drug residues in animals,threats to human health.Therefore,it is necessary to strictly monitor the drug residues in animal derived food.An ultra performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS）method coupled with molecularly imprinted solid phase extraction（MISPE）for the determination of 23 quinolones residues in chicken was established.1.The established UPLC-MS/MS analysis condition for simultaneous determination of 23 quinolones was optimized.The mass spectrometry conditions of mass spectrometry ionization,quantitative ion,qualitative ion,cone voltage,collision energy,parent ion and daughter ions were optimized respectively.Meawhile,the chromatographic conditions of mobile phase composition and ratio,gradient elution conditions were optimized respectively.The drugs were analyzed on BEH C₁₈8 column by gradient elution with acetonitrile and 0.1%（v/v）formic acid solution as mobile phase.The samples were analyzed in electrospray positive ion mode and multiple reaction monitoring（MRM）mode.The analytes were quantified by the external standard quantitative method.2.To optimize the conditions for the purification,loading volume,washing,elution and eluent volume of 23 quinolones in MISPE column.Finally determine the loading volume of 4 mL,2 mL water,2 mL acetonitrile and 2 mL 2%（v/v）acetic acid acetonitrile,2 mL 0.1%（v/v）ammonia washing,3 mL 5%（v/v）ammoniated methanol elution conditions.The samples were extracted with phosphate buffer solution,and cleaned up with MISPE columns.Then the column was washed followed by water,acetonitrile,2%（v/v）acetic acid acetonitrile,0.1%（v/v）aqueous ammonia,and eluted with 5%（v/v）ammoniated methanol.The specific adsorption of MISPE for the 23 quinolones in chicken samples was investigated.The maximum capacities of the MISPE column were470.6-898.3μg/L.The reusability of MISPE was investigated.MISPE column can be reused at least 11 times with the recovery rate reached more than 80%,the coefficient of variation of each drug in 1.5%-14.9%.3.The evaluation of the linear relationship,detection limit,quantitative limit,accuracy,precision,matrix effect and sensitivity of the MISPE-UPLC-MS/MS method for simultaneous determination of 23 quinolones in chicken were evaluated.The results showed that the linear ranges were 0.25-200μg/L,with correlation coefficients（r）greater than 0.99.The limits of detection（LODs,S/N=3）and the limits of quantification（LOQs,S/N=10）were 0.08μg/kg and 0.25μg/kg,respectively.At the spiked levels of 0.25,2.5,5μg/kg,the recoveries were 88.6%-103.3%with the inter-or intra-RSDs of 0.7%-10.5%and0.6%-13.2%,respectively.The matrix had no effect on the analysis results.The method is sensitive,simple and rapid for the simultaneous determination of the nine fluoroquinolone residues.4.The 80 samples of chicken samples collected from a slaughterhouse in Shandong Province were tested by using the optimized MISPE-UPLC-MS/MS method.The results were in accordance with the results obtained by the method of GB/T 20366-2006.