QuEChERS-高效液相色谱-串联质谱法测定多果定在黄瓜和土壤中的残留及消解动态

Residue and degradation of dodine in cucumber and soil investigated by QuEChERS-high performance liquid chromatography-triple quadrupole tandem mass spectrometry

建立了黄瓜和土壤样品中多果定的Qu ECh ERS-高效液相色谱-电喷雾串联质谱(HPLC-ESI-MS/MS)检测方法,样品经甲醇(乙腈+甲醇)溶液,Qu ECh ERS方法净化,以Agilent ZORBAX Eclipse Plus C_(18)(2.1 mm×50 mm,1.8μm Rapid Resolution HD)色谱柱进行高效液相色谱分离,以电喷雾离子串联质谱正离子(ESI+)多反应监测(MRM)模式进行测定.多果定在黄瓜和土壤上的最低检出浓度(LOQ)为0.01 mg·kg^(-1),平均回收率为77.7%—113.4%,相对标准偏差(RSD)为1.5%—8.0%;多果定在黄瓜和土壤上的残留消解动态规律符合一级动力学方程,其半衰期分别为2.3—4.3 d和2.7—17.3 d.该方法样品前处理简单快速,分析时间短,灵敏度、准确度和精密度均符合农药残留检测要求,适用于黄瓜和土壤中多果定残留的检测.

A method was developed for the determination of dodine residues in cucumber and soil by employing Qu ECh ERS-high performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry（ HPLC-ESI-MS/MS）. The residues in the samples were extracted by methanol or acetonitrile/methanol（ 2∶1,V/V）,cleaned up by developed Qu ECh ERS method,and then analyzed by using LC-MS/MS in multiple reaction monitoring（ MRM） mode via positive electro spray ionization with an Agilent ZORBAX Eclipse Plus C（18） column（ 2.1 mm×50 mm,1.8 μm RapidResolution HD Agilent） as the analytical column. The limit of quantification（ LOQ） was0.01 mg·L（-1）. The range of average recovery were 77.7%—113.4%. The relative standard deviations（ RSD） were 1.5%—8.0%.The dissipation dynamics of dodine residues in cucumber and soil fitted the first-order kinetic equation,and the dissipation half-life of dodine in cucumber and soil was2.3—4. 3 d and 2. 7—17. 3 d. The method is simple,rapid and characterized with acceptable sensitivity and accuracy to meet the requirements of the pesticide residue analysis. This method is applicable for the detection of dodine residues in cucumber and soil.