Injection-ultrasound-assisted emulsification microextraction based on using low-density organic solvent followed by high-performance liquid chromatography for the determination of pyrethroids in water samples

A highly efficient, simple and rapid method, injection-ultrasound-assisted emulsification microextraction based on using low-density organic solvents followed by high-performance liquid chromatography-ultraviolet detection, was developed for the determination of trace level pyrethroids in water samples. Various parameters influencing the extraction efficiency, such as type of extractant, extractant volume, ultrasonic time, centrifugation time and salt addition, were studied and optimized by two methods: the single factor experiment and the Box–Behnken design. Under the optimum conditions, great enrichment factors (678–713) and good recoveries (92.48–97.31%) were obtained for the extraction and analysis of artificial water samples. Linearity of the method for three pyrethroids was in the range of 0.11–218 μg L−1 for fenpropathrin, and 0.07–136 μg L−1 for fenvalerate and permethrin, respectively, with correlation coefficients ranging from 0.9994 to 0.9999. The limits of detection for the target analytes were 12.13 to 20.16 ng L−1, and the limits of quantification were 40.43 to 67.19 ng L−1. The recoveries of the three pyrethroids from actual water samples at three spiked levels were in the range of 83.25 to 103.3% with relative standard deviation RSDs less than 7.40%.