固相萃取-液相色谱测定复杂基质蔬菜中9种烟碱类残留

Determination of Nicotinoid Residues in Complicated Matrix Vegetables by Solid Phase Extraction and HPLC Method

建立了韭菜、洋葱、大蒜等复杂基质蔬菜样品中呋虫胺、烯啶虫胺、氟啶虫酰胺、噻虫嗪、吡虫啉、噻虫胺、氯噻啉、啶虫脒、噻虫啉9种烟碱类农药残留的液相色谱检测方法。对比了几种常用溶剂的提取效率以及固相萃取材料对韭菜、洋葱样品中干扰基质的去除效果。研究结果表明，样品经微波处理后，用乙腈提取，Envi—Carb／PSA固相萃取柱净化，乙腈洗脱后，经反相高效液相色谱紫外检测器检测，在0．02～0．5mg／kg加标水平下9种烟碱类农药的回收率为67％～110％，相对标准偏差均小于18．6％。所检测的3种蔬菜样品中除噻虫啉的定量下限为0．05mg/kg外，其他8种农药的定量下限均不大于0．02mg/kg。方法简便、快速，可满足复杂基质蔬菜中烟碱类农药多残留分析的要求。

A simple and sensitive high performance liquid chromatographic （HPLC） method was developed for the simultaneous determination of 9 nieotinoid insecticide residues, ineluding dinotefuran, nitenpyram, flonieamid, thiamethoxam, imidacloprid, clothianidin, imidaelothiz, acetamiprid and thiaeloprid, in sulphur-containing vegetables samples. The extract efficieneies of several solvent and the cleanup capacities of different SPE cartridges were compared. The vegetables were extracted with aeetonitrile and cleaned up on an Envi -Carb/PSA cartridge. The nieotinoid insecticides were eluted with aeetonitrile and detected with UV detector. The calibration curves showed good linearities in the range of 0. 02 - 1.0 mg/L with correlative coefficient more than 0. 999. The limits of quantitation （LOQ） were 0.02 mg/kg for all 9 pesticide except for thiacloprid with LOQ of 0. 05 mg/kg. The recoveries of 9 pesticides from vegetable sample spiked at three concentration levels of 0.02 mg/kg, 0.05 mg/kg and 0.5 mg/kg ranged from 67% to 110% with RSDs less than 18.6% . The established method was simple, sensitive and accurate, and was suitable tot the routine detection of nicotinoid pesticides residues in vegetables.