Determination of organophosphorous pesticides in water samples using ionic liquid-based liquid phase microextraction coupled with high performance liquid chromatography

A novel method for the determination of three organophosphorous pesticides (phorate, parathion and poxim) in water samples has been developed using ionic, liquid-based liquid-phase microextraction coupled with high performance liquid chromatography. The influence of extraction parameters including extraction solvent, the volume ratio of extraction solvent to sample aqueous, extraction time, extraction temperature and stirring rate was investigated. 1-butyl-3-methylimi dazolium hexafluorophosphate was used as extraction solvent and displayed particular advantages compared with volatile organic solvents such as benzene, hexane and acetone. The proposed method provided enrichment folds of 665, 630 and 553 for phorate, parathion and poxim, respectively. The method had good linear range of 0.01 - 0.1 mu L/L and the limits of detection of the three pesticides were in the range of 0.001 - 0.01 mu L/L. The RSD of matrix spiked samples were 3.4%, 10.5% and 2.4% for phorate, parathion and poxim, respectively.