应用DPX方法快速测定蔬菜中有机磷残留量

GC determination of residual amounts of organophosphorus pesticides in vegetables with DPX

目的应用DPX方法快速处理样品,气相色谱法测定蔬菜中的22种有机磷残留量。方法蔬菜经乙腈提取后用DPX-Q吸管净化,提取液用氮吹法浓缩近干,残渣二氯甲烷溶解定容到0.5 ml,采用DB-1701 MS毛细管柱分离,火焰光度检测器测定有机磷农药。结果样品加标回收率为80.5%～102%,相对标准偏差(n=6)为3.2%～9.6%,检出限(3 S/N)为0.006～0.019 mg/kg。结论该实验方法简便、快速、灵敏、准确,各项技术指标能满足蔬菜中有机磷农药检测需要。

Objective Gas chromatography was applied to the determination of residual amounts of 20 organophospho- rus perstieides in vegetables with sample pre-treatment by DPX method. Methods The pesticides were separated from wegeta- ble samples extraction with acetonitrile and the extract was purified by DPX-Q. The filtrate was taken and evaporated to fryness byN2-blowing, and the residues were taken up to 0. 5ml of dichloromethane separately, which were used for separation on DB- 1701MS chromatographic column. Flame photometric detector was used in the determination for organophosphorus persticides. Results Values of recovery found were ranged from 80. 5% to102%, withrsd＇s （n=6） in the range of 3. 2% to9.6%, De- tection limits （3S/N） in the range of 0. 006 - 0. 019mg/kg. Conclusion The method is simple, rapid, sensitive and accu- rate, The technical specifications are suitalle for the detection of organophosphorus persticides in vegetables.