韭菜中吡虫啉和啶虫脒残留的微波处理-逆固相分散法净化及液相色谱检测

建立了韭菜中两种烟碱类农药吡虫啉和啶虫脒残留的快速检测方法.韭菜样本用微波炉加热处理,使酶钝化消除含硫基质干扰,然后用乙腈提取、逆固相分散净化,用反相高效液相色谱-二极管阵列检测器检测.在0.05～2.0 mg/kg添加水平范围内,吡虫啉的平均添加回收率在95.2%～105.3%之间;相对标准偏差在0.8%～7.8%之间;啶虫脒的平均添加回收率在97.4%～108.8%之间;相对标准偏差在1.3%～8.3%之间.本方法对吡虫啉的检出限(LOD)为0.0078 mg/kg,定量检出限(LOQ)为0.026 mg/kg;对啶虫脒的检出限为0.0075 mg/kg,定量检出限为0.025 mg/kg.

Determination of Imidacloprid and Acetamiprid in Leek by Reversed Phase High Performance Liquid Chromatography with Microwave Treatment and Convenient Reverse Solid Phase Dispersion Clean-up

A rapid method has been developed for the determination of two neonicotinoid insecticide residues including imidacloprid and acetamiprid in leek.The samples of leek were treated with microwave to make the enzyme inactive and to eliminate the matrix interferences.Then the pretreated samples were extracted with acetonitrile,further cleaned up by reverse solid phase dispersion,and analyzed by reversed phase HPLC with diode array detector(DAD).Average recoveries of imidacloprid and acetamiprid were found in the range of 95.2%-105.3% and 97.4%-108.8% at three spiking levels from 0.05 mg/kg to 2.0 mg/kg with relative standard deviations of 0.8%-7.8% and 1.3%-8.3%,respectively.Limit of detections of imidacloprid and acetamiprid were 0.0078 mg/kg and 0.0075 mg/kg,while limit of quantifications were 0.026 mg/kg and 0.025 mg/kg,respectively.