基于低共熔溶剂的液液微萃取技术测定食用油中的新烟碱类杀虫剂

利用合成的低共熔溶剂(deep eutectic solvent,DES)作为液液微萃取技术中的萃取剂,利用超声波辅助分散,建立高效液相色谱测定食用油中4种新烟碱类杀虫剂(噻虫嗪、吡虫啉、啶虫脒、噻虫啉)的方法.首先将合成的DES加入到含有目标分析物的食用油(正己烷稀释)中,进行超声辅助分散加速提取,然后离心,吸出上层...

Liquid Phase Microextraction with Deep Eutectic Solvent Combined with High Performance Liquid Chromatography for Determination of New Neonicotinoid Insecticide Residues in Edible Oil

In this study, a method for the determination of residues of four new neonicotinoid insecticides (thiamethoxam, imidacloprid, acetamiprid, and thiacloprid) in edible oil was developed using ultrasound-assisted liquid-liquid microextraction with deep eutectic solvent (UA-DES-LLME) followed by high performance liquid chromatography (HPLC). Samples were diluted with n-hexane and added with deep eutectic solvent (DES) before being subjected to ultrasonic-assisted dispersive liquid-liquid microextraction (UALLME). Then, the extract was centrifuged. The lower DES-rich phase was collected and injected into the HPLC system for analysis. Several important parameters influencing the extraction efficiency, such as the type and volume of DES, ultrasonication time, and centrifugation time, were investigated. Under the optimized conditions, the recoveries of the analytes were between 81.9% and 98.0%, with relative standard deviations (RSD, n = 5) of 5.5%–8.3%. The limits of detection (LODs) and limits of quantitation (LOQs) were 3.2?5.3 μg/L and 10.8?17.7 μg/L respectively. The method was successfully applied to real samples of soybean oil, sunflower seed oil and linseed oil. This method combined extraction and concentration in one step without the use of poisonous organic solvents. This method proved to be simple, rapid and efficient.