气相色谱-质谱联用法测定水果中四螨嗪残留量

GC-MS Determination of Residual Clofentezine in Fruits

提出了气相色谱-质谱联用法（GC-MS）、用选择离子监测方式（SIM）测定水果中四螨嗪残留量。试样用水-丙酮（1＋4）振荡提取,经二氯甲烷液-液分配,以凝胶色谱柱净化,再经氟罗里硅土固相柱净化,洗脱液浓缩并溶解定容后,供气相色谱-质谱仪检测,外标法定量。回收率范围为83.8%-91.6%,相对标准偏差（n=10）为5.1%-7.4%,测定限为0.010 mg·kg^-1。

Clofentezine in fruit sample was extracted with acetone and water mixed in the ratio of 4 to 1, and then partitioned with dichloromethane. The analyte in dichloromethane was purified by passing successively through gel-chromatographic column and Florisil solid phase extraction （SPE） column. The eluate from the Florisil SPE column was evaporated to dryness in a water bath at 40 ℃, The residue was taken up with acetone and made up to 2. 00 mL with acetone, which was used for GC-MS determination, with external standard method. Detection limit of the method was found to be 0. 010 mg · kg^-1. Recovery test was made by standard addition method, and values of recovery obtained were in the range from 83. 8% to 91. 6%. Test for precision was performed at 3 different concentration level, giving values of RSD＇s （n=10） in the range of 5. 1 %--7. 4%.