单滴液相微萃取-高效液相色谱法测定水中二甲戊乐灵农药残留

Determination of Pendimethalin in Water by Single Drop Liquid Phase Microextraction-High Performance Liquid Chromatography

应用单滴液相微萃取(SD-LPME)技术建立了水体中二甲戊乐灵农药的高效液相色谱(HPLC)分析方法。研究了不同的萃取条件(萃取剂、体积、萃取时间、搅拌速度、温度等)及测定条件对检测二甲戊乐灵的影响,确定了最佳萃取条件:环己烷作萃取剂,萃取剂体积5μL,液滴体积2μL,搅拌速度350r/min,35℃条件下萃取35min。应用此方法测定了自来水和太湖水样中的二甲戊乐灵农药残留,相对标准偏差(RSD)在2.5%～3.4%(n=6)之间;回收率为88.0%～99.8%。

Single Drop Liquid phase microextraction-high performance liquid chromatography was established for the determination of pendimethalin in water. In order to optimize the experimental conditions, the effects of different extraction（extraction solvent, solvent volume, extraction time, stirring rates and temperature） and measuring conditions on detection of pendimethalin were investigated. Optimal experimental conditions were as follows： organic solvent, organic solvent volume, drop volume, stirring rate ,solution temperature, and extractiun time were： cyclohexane, 5 μL, 2 μL, 350 r/min, 35℃ and 35 min, respectively. The pendimethalin residues in the tap water and Tai lake were determined by this method. The relative standard deviations of the method ranged from 2.5% to 3.4%（n=6）, and the recoveries were 88.0% -92.6%.