高效液相色谱-串联质谱法测定婴幼儿米粉中29种三嗪类除草剂残留

Determination of 29 triazine herbicides in infant rice flour by high performance liquid chromatography-tandem mass spectrometry

采用改良的QuEChERS方法结合高效液相色谱-串联质谱(HPLC-MS/MS)法建立了婴幼儿米粉中同时测定29种三嗪类除草剂残留量的分析方法。米粉样品经6 mL水浸润后,用乙腈:乙酸乙酯(1:1,V/V)提取,N-丙基乙二胺(PSA)和无水MgSO4净化,经ZORBAX Eclipse XDB-C_(18)色谱柱分离,采用正离子模式扫描,多反应监测(MRM)模式检测,外标法定量。结果表明29种三嗪类除草剂线性关系良好,相关系数R^(2)大于0.999,方法的检出限为0.01~0.51μg/kg,定量限在0.04~1.70μg/kg之间。3个加标水平下的平均回收率在71.1%~111.4%之间,相对标准偏差(RSDs)0.9%~8.8%。该方法适用于婴幼儿米粉中29种三嗪类除草剂残留的同时快速检测。

A method was established for the simultaneous determination of 29 triazine herbicides in infant rice flour by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS),based on the modified QuEChERS.After mixing with 6 mL of water,the rice flour samples were extracted with acetonitrile:ethyl acetate(1:1,V/V),and purified with N-propyl ethylenediamine(PSA)and anhydrous magnesium sulfate(MgS04),then the samples were separated by ZORBAX Eclipse XDB-C_(18) column,and determined by multiple reaction monitoring(MRM)with positive ion mode scanning and quantified by the external standard method.The results showed that 29 triazine herbicides had good linear relationships,with the correlation coefficients(R^(2))greater than 0.999.Moreover,the limits of detection of the method were 0.01-0.51μg/kg,and the limits of quantitation were 0.04-1.70μg/kg.The average recoveries at 3 spiked levels were 71.1%-111.4%,with relative standard deviations(RSDs)of 0.9%-8.8%.The method is suitable for the rapid and simultaneous detection of 29 triazine herbicide residues in infant rice flour.