分散固相萃取-气相色谱-质谱法测定水果和蔬菜中扑草净和禾草丹残留量

GC-MS Determination of Residual Amounts of Prometryne and Thioencarb in Fruits and Vegetables with Dispersive Solid Phase Extraction

以乙腈作萃取溶剂,乙二胺-N-丙基硅烷（PSA）为吸附剂对水果和蔬菜中残留的扑草净和禾草丹进行固相分散萃取。提取液供气相色谱-质谱仪测定,外标法定量。在优化的试验条件下,选定m/z241和m/z100分别作为扑草净和禾草丹的定量离子,在选择离子监测模式下,扑草净和禾草丹的线性范围均为0.05-10.0 mg·L^-1。用标准加入法测得两除草剂的回收率分别在89.0%-92.0%和92.0%-95.0%之间,相对标准偏差（n=6）均小于7%

Residual amounts of prometryne and thioencarb in samples of fruit and vegetable were extracted by dispersive sold phase extraction（DSPE） technique with acetonitrile as extraction solvent and PSA as adsorbent.The eluate was determined by GC-MS,and external standard calibration was adopted in the determination.Under the optimized conditions,the ions with m/z 241 and 100 were selected as quantitative ions for the determination of prometryne and thioencarb respectively.Linearity ranges for both prometryne and thiencarb were between 0.05-10.0 mg·L^-1.The values of recovery for prometryne and thioencarb found by standard addition method were in the ranges of 89.0%-92.0% and 92.0%-95.0%,respectively,and values of RSD′s（n=6） found were less than 7%.