Abstract：
In this study, an efficient preconcentration method was presented that is based on dispersive liquid-liquid microextraction taking the advantage of newly synthesized phosphonium deep eutectic solvents used as extractants and ultrasound probe as a dispersing agent. The extracts obtained were analyzed by high-performance liquid chromatography. To optimize the five most important factors for the microextraction procedure a central composite design plan was used. Under optimal conditions (140 μl of extractant, 60 mg of NaCl, pH = 2.0, 120 s of extraction time with ultrasound probe as the dispersing agent, 16 min of centrifugation for phase separation), the proposed method allowed to achieve good precision with RSD between 3.2% and 9.7% at 1.0, 5.0 and 40.0 ng ml levels. The preconcentration factors were equal to 42, 39, and 41, and the limits of detection 0.128, 0.103, and 0.135 ng/ml for dicamba, 2-methyl-4-chlorophenoxyacetic acid, and 2-methyl-4-chlorophenoxypropionic acid, respectively. The proposed method was successfully applied for the determination of chlorophenoxy acid herbicides in water samples from drainage ditches with a good recovery in the range of 70%-93%.
摘要：
在这项研究中,提出了一种有效的预浓缩方法，该方法基于分散液-液微萃取，利用新合成的鳞深共晶溶剂作为萃取剂，超声探针作为分散剂。通过高效液相色谱法分析获得的提取物。为了优化微萃取程序的五个最重要因素，使用了中央复合设计计划。在最佳条件下（140μl萃取剂，60mgNaCl,pH=2.0，超声探头为分散剂的提取时间为120s，离心16分钟进行相分离)，在1.0、5.0和40.0ngml水平下，所提出的方法可以达到良好的精度，RSD在3.2％至9.7％之间。前富集因子分别为42、39和41，麦草畏的检出限为0.128、0.103和0.135ng/ml，2-甲基-4-氯苯氧基乙酸,和2-甲基-4-氯苯氧基丙酸，分别。该方法已成功应用于排水沟水样中氯苯氧基除草剂的测定，回收率在70％-93％之间。
