China Agricultural University, Beijing 100193, China.
Anal Bioanal Chem. 2010 Aug;397(7):3089-95. doi: 10.1007/s00216-010-3841-2. Epub 2010 Jun 5.
A simple, rapid and efficient ionic liquid based on dispersive liquid-phase microextraction (IL-DLPME) method was developed for the determination of three triazine and two phenylurea herbicides in water samples. IL (1-hexyl-3-methylimidazolium hexafluorophosphate [C(6)MIM][PF(6)]) that dispersed completely into the water solution under controlled temperature was used as the extraction solvent. The analytes were easily concentrated into the ionic liquid phase. This technique combined the process of extraction and concentration of the analytes into one step and avoided use of the more common, toxic organic solvents. The factors affecting the extraction efficiency such as the IL volume, sample pH, extraction time, centrifugal time, dissoluble temperature and ionic strength were optimized. The extracts were analyzed by high-performance liquid chromatography (HPLC) coupled with diode array detector (DAD). Under the optimized conditions, recoveries (50.5-109.1%) were obtained for the target analytes in water samples. The calibration curves were linear and the correlation coefficient ranged from 0.9947 to 0.9973 in the concentration levels of 5-100 microg L(-1). The relative standard deviations (RSDs, n = 5) were 6.80-10.78%. The limit of detections (LODs) for the five polar herbicides were between 0.46 microg L(-1) and 0.89 microg L(-1).
建立了一种基于离子液体分散液相微萃取（IL-DLPME）的简单、快速、高效的方法，用于测定水样中的三种三嗪类和两种苯脲类除草剂。离子液体（1-己基-3-甲基咪唑六氟磷酸盐[C（6）MIM][PF（6）]）在控温下完全分散于水溶液中，用作萃取溶剂。目标分析物很容易被浓缩到离子液体相中。该技术将萃取和浓缩分析物的过程合二为一，避免了使用更常见的有毒有机溶剂。优化了影响萃取效率的因素，如 IL 体积、样品 pH 值、萃取时间、离心时间、溶解温度和离子强度。采用高效液相色谱（HPLC）-二极管阵列检测器（DAD）对提取物进行分析。在优化条件下，水样中目标分析物的回收率为 50.5%-109.1%。在 5-100μg/L 的浓度水平下，校准曲线呈线性，相关系数范围为 0.9947-0.9973。相对标准偏差（RSD，n=5）为 6.80%-10.78%。五种极性除草剂的检出限（LODs）在 0.46μg/L-0.89μg/L 之间。
