QuEChERS结合柱净化的超高效液相色谱-串联质谱法测定有机肥中46种抗生素

Determination of 46 Antibiotics Residues in Organic Fertilizer by UPLC-MS/MS with QuEChERS Combined with Column Purification

建立了超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定有机肥中磺胺类、喹诺酮类、大环内酯类46种抗生素的分析方法。样品用乙腈-EDTA缓冲溶液(p H 10.0)提取,盐析后离心分层,乙腈层按Qu ECh ERS法,采用吸附剂净化;缓冲溶液层经HLB柱净化。ACQUITY UPLC BEH C18柱用作色谱分离,以2mmol/L甲酸铵水溶液(含0.1%甲酸)-甲醇为流动相进行梯度洗脱;电喷雾电离源正离子(ESI+)多反应监测(MRM)模式检测,基质外标法定量。46种抗生素在1~200μg/L范围内线性关系良好,相关系数(r2)为0.996 6~0.999 9。在25,100,400μg/kg加标浓度下,3类抗生素的回收率分别为67.8%~95.6%,65.6%~89.4%和66.6%~107.8%,相对标准偏差为0.4%~11.9%;方法检出限(S/N=3)为0.6~4.6μg/kg,定量下限(S/N=10)为2.1~15.4μg/kg。

A confirmative method was developed for the simultaneous determination of 46 antibiotics,including sulfonamides,quinolones and macrolides in organic fertilizer by ultrahigh performance liquid chromatography-tandem massspectrometry（UPLC-MS/MS）. The samples were extracted with acetonitrile-EDTA buffer solution（p H 10. 0）,and separated by centrifugation after salting-out. The upper acetonitrile layer was purified by the Qu ECh ERS steps with sorbents. The buffer solution layer was purified with solid-phase extraction cartridge. The separation of target drugs was performed on an ACQUITY UPLC BEH C18 column using a mobile phase consisting of 2 mmol/L ammonium acetate with 0. 1% formic acid and methanol by gradient elution. The analysis of target compounds was carried out with positive electrospray ionization（ESI ＋） source under multiple reaction monitoring（MRM） mode. The matrix-matched external standard calibration was used for quantification. Good linearities for the 46 antibiotics were achieved over the concentration of 1-200 μg/L,with correlation coefficients（r^2） of 0. 996 6-0. 999 9. The recoveries of sulfonamides,quinolones and macrolides at spiked levels of 25,100,400 μg/kg were in the range of 67. 8%-95. 6%,65. 6%-89. 4% and 66. 6%-107. 8%,respectively,with relative standard deviations（RSDs） of 0. 4%-11. 9%. The limits of detection（LOD,S/N = 3） were 0. 6-4. 6 μg/kg,and the limits of quantitation（LOQ,S/N = 10） were 2. 1-15. 4 μg/kg.