Abstract
A novel and greener methodology for the simultaneous preconcentration of organochlorine pesticides in water samples based on ultrasound assisted-homogeneous liquid-liquid phase microextraction (UA-HLLME) has been developed. Gas chromatography-time of flight mass spectrometry was used for quantification of OCPS in water samples. In this method, choline-chloride-ethylene glycol deep eutectic solvent and ethyl acetate were used as the disperser solvent and extraction solvent, respectively. Univariate and multivariate approaches were used for optimization of the influential parameters that affect the extraction efficiency of the UA-HLLME method. Under the optimum conditions, enrichment factors ranging from 152 to 403 with acceptable recoveries of 85-100% were obtained. The dynamic linear ranges were obtained in the concentration range 0.015–1000 μg L−1 with correlation coefficients ranging 0.9952–0.9995. The limits of detection and quantification of the developed UA-HLLME method were in the range 1.9-8.6 ng L−1 and 5.9-26 ng L−1, respectively. The intra-day and inter-day precision expressed in terms of relative standard deviation (%RSD) ranged from 2.1-4.5% and 3.9-7.3%, respectively. The developed method was successfully applied for the preconcentration and determination of the selected OCPs from 3 different river water samples. The developed procedure displayed simplicity, environmental friendliness, relatively high extraction efficiency, short analysis time and relatively low detection limits.