气相色谱法同时测定荞麦中百菌清、三唑酮和拟除虫菊酯类农药残留量

Simultaneous GC Determination of Chlorothalonil,Triadimefon and Pyrethrin Pesticide Residues in Buckwheat

摘要: 采用气相色谱法同时测定荞麦中百菌清、三唑酮和拟除虫菊酯类农药残留量.样品经石油醚-丙酮(4＋1)混合溶剂提取后,所得提取液经层析柱净化浓缩,于气相色谱(带电子捕获检测器)测定.百菌清、三唑酮和4种拟除虫菊酯类杀虫剂的线性范围均为0.02~5.0 mg·L-1,方法的检出限(3S/N)均小于0.02 mg·L-1.在三个标准加入水平下进行了回收率和精密度试验,所得回收率在80.4%~111.6%之间,相对标准偏差(n=8)小于8.0%.

Abstract: Gas chromatography was applied to the determination of residual chlorothalonil,triadimefon and pyrethrin pesticides in buckwheat.The sample was extracted with a mixture of petroleum ether and acetone(4+1),and the extract obtained was purified and concentrated on chromatographic column.The eluate from the chromatographic column was used for GC (with ECD) analysis.Linearity ranges of chlorothalonil,triadimefon and 4 pyrethrin pesticides were kept in the range of 0.02-5.0 mg·L-1,with detection limits (3S/N) less than 0.02 mg·L-1.Tests for recovery and precision were made by standard addition method at 3 different concentration levels,values of recovery found were in the range of 80.4%-111.6% and values of RSD′s (n=8) were less than 8.0%.