GC/MS法测定大米中精噁唑禾草灵和氰氟草酯残留量

采用乙腈提取,NH2固相萃取柱净化,GC/MS测定,建立了大米中精噁唑禾草灵和氰氟草酯残留量的测定方法。添加精噁唑禾草灵质量分数为0.02,0.2,0.5mg/kg,平均回收率分别为82.3%,88.8%和90.7%,相对标准偏差分别为6.8%,8.2%和3.7%,检出限为0.02 mg/kg;添加氰氟草酯质量分数为0.02,0.2,0.5mg/kg,平均回收率分别为87.7%,94.2%和92.3%,相对标准偏差分别为8.6%,5.6%和7.3%,检出限为0.02mg/kg。

Determination of fenoxaprop-p-ethyl and cyhalofop-butyl in rice by GC/MS

Rice samples were extracted with acetonitrile,and cleaned up by a NH2 solid phase extraction column.An accurate GC/MS method for the determination of fenoxaprop-p-ethyl and cyhalofop-butyl in rice was developed.Precision and accuracy of fenoxaprop-p-ethyl were assessed by adding fenoxaprop-p-ethyl into rice at three concentration levels(0.02,0.2 and 0.5mg/kg) using five replicates at each level.The average recoveries of fenoxaprop-p-ethyl were 82.3%,88.8% and 90.7% with the RSDs between 3.7% and 8.2%,and the limit of detection was 0.02 mg/kg.Likewise,precision and accuracy of cyhalofop-butyl were assessed by adding cyhalofop-butyl into rice at three concentration levels(0.02,0.2 and 0.5mg/kg) using five replicates at each level.The average recoveries of cyhalofop-butyl were 87.7%,94.2% and 92.3% with the RSDs between 5.6% and 8.6 %,and the limit of detection was 0.02 mg/kg.