Determination of Three Pyrethroid Insecticides in Food by Magnetic Ionic Liquid-Based Dispersive Liquid Phase Microextraction (DLLME) with High-Performance Liquid-Chromatography (HPLC)

A simple, green, rapid, and efficient magnet ionic liquid (MIL) dispersive liquid–liquid microextraction (DLLME) method coupled with high-performance liquid chromatography (HPLC) was successfully developed for the determination of three trace pyrethroids (fenvalerate, beta-cypermethrin, and bifenthrin) in water and food samples. Tri-hexyl-tetradecyl-phosphonium tetra-chlorocobalt (II) [P6,6,6,14+]2[CoCl42−] was explored as the extraction solvent due to its magnetic susceptibility, low ultraviolet absorbance, difficulty to hydrolyze in aqueous solution, and high extraction capacity. Important factors of extraction efficiency, such as the mass of MIL, pH, and ionic strength, were optimized. The spiked recoveries of the targets in water and food samples were from 96.3 to 103.8%. The detection limits were from 0.75 to 1.75 ng ml−1. The results indicated that the developed MIL-DLLME method based on [P6,6,6,14+]2[CoCl42−] as the extraction solution has the advantages of rapid and high efficiency and was employed to determine pyrethroids in water and food samples.