Effervescence-assisted dispersive liquid-liquid microextraction for extraction and preconcentration of organochlorine pesticides in water samples

Abstract

ABSTRACT. In this paper, effervescence-assisted dispersive liquid-liquid microextraction method has been developed for the extraction and preconcentration of organochlorine pesticides in water samples before their determination by gas chromatography-mass spectrometry. The method involves in-situ generation of CO2 bubbles to induce dispersion of the extraction solvent in the aqueous sample. Different parameters affecting the extraction efficiency of the method including the type and concentration of the effervescent agents as well as the type and volume of extraction solvent were optimized. Under optimum conditions, matrix matched calibration curves were constructed at eight concentrations ranging from 0.6–4.0 ng/mL showed good linearity with coefficient of determinations of ≥ 0.9961. The limits of detections and quantifications ranged from 0.2–0.4 and 0.6–1.0 ng/mL, respectively. The intra- and inter-day precisions studied at two concentration levels had below 5% relative standard deviation values. Similarly, recoveries investigated at two concentration levels ranged from 80.7–117.4%. The findings demonstrated that proposed method is simple, rapid, and efficient to be used as alternative method for analysis of organochlorine pesticides from environmental water and other similar matrices.   KEY WORDS: Effervescence agents, CO2 bubbles, Organochlorine pesticides, Water samples, gas chromatography-mass spectroscopy   Bull. Chem. Soc. Ethiop. 2023, 37(5), 1109-1122.                                                            DOI: https://dx.doi.org/10.4314/bcse.v37i5.4