Low-density solvent-based vortex-assisted surfactant-enhanced emulsification liquid–liquid microextraction and its application


Correspondence: Dr. Peng Wang, Department of Applied Chemistry, China Agricultural University, Beijing, 100193, P. R. China

E-mail: wangpeng@cau.edu.cn

Fax: +86 010-62732937


For the first time, the low-density solvent-based vortex-assisted surfactant-enhanced emulsification liquid–liquid microextraction, followed by GC-flame photometric detection has been developed for the determination of eight organophosphorus pesticides in aqueous samples. A small volume of organic extraction solvent (toluene) was dispersed into the aqueous samples by the assistance of surfactant and vortex agitator. The extraction was performed in a special disposable polyethylene pipette, allowing using the reagents with lower density than water as extraction solvents. The influence parameters were systemically investigated and optimized: toluene (30 μL) and Triton X-100 (0.2 mmol/L) were used as the extraction solvent and the surfactant, respectively, and the extraction was performed for 1 min under room temperature without adding sodium chloride. Under the optimum conditions, the validation parameters such as the RSD (n = 6; 2.1–11.3%), LOD (0.005 and 0.05 μg/L), and linear range (0.1–50.0 μg/L with correlation coefficients (0.9958–0.9992) showed the method was satisfying. The proposed method has been successfully applied to the determination of the organophosphorus pesticides in real samples with recoveries between 82.8 and 100.2%.