分散固相萃取-液相色谱-串联质谱法测定农产品中吡氟甲禾灵

Determination of haloxyfop-etotyl in agricultural products by dispersive solid phase extraction and liquid chromatography-mass spectrometry

应用液相色谱-串联质谱联用技术,建立了农产品中吡氟甲禾灵的分析方法。样品经乙腈提取,无水Mg2SO4和NaCl混合盐盐析,N-丙基乙二胺、C18填料分散固相萃取净化;采用乙腈和5 mmol/L甲酸铵水溶液为流动性,二元梯度洗脱,C18(2.1×150 mm,3.5μm)色谱柱分离;电喷雾正离子模式采集,多反应监测模式测定。结果表明:吡氟甲禾灵在0.5～500μg/kg范围内线性关系良好,相关系数(r)为0.9999;在农产品中进行4个加标水平,平均回收率(n=3)为75.4%～113.8%,相对标准偏差为0.6%～9.2%;方法检测限为0.5μg/kg,定量限为2μg/kg。方法适用于农产品中吡氟甲禾灵的分析。

A method was developed for the determination of Haloxyfop-etotyl in agricultural products using liquid chromatography tandem mass spectrometry.The sample was extracted with acetonitrile,and salted out by anhydrous magnesium sulfate and sodium chloride,then cleaned up utilizing dispersive solid-phase extraction contained PSA（primary secondary amine） and C18.Haloxyfop-etotyl was separated on a C18（2.1×150 mm,3.5 μm） column with gradient elution employing acetonitrile and 5 mmol/L ammonium formate as mobile phase,and finally detected with positive-ion electrospray ionization-mass spectrometry in multiple reaction monitoring mode.The results showed good linearity over the range of 0.5～500 μg/kg for Haloxyfop-etotyl with the correlation coefficient of 0.9999.The Haloxyfop-etotyl was measured in fortified agricultural products at four spiked levels,and the mean recoveries（n=3） were in the range of 75.4%～113.8% with the relative standard deviations of 0.6%～9.2%.The limit of detection（LOD） was 0.5 μg/kg,and the limit of quantification（LOQ） was 2 μg/kg.The method is simple,sensitive,selective and suitable for determination of Haloxyfop-etotyl residue in agricultural products.