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

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。

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

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 (pH 10.0),and separated by centrifugation after salting-out.The upper acetonitrile layer was purified by the QuEChERS 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 C1scolumn 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 (r2) 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.