Hollow fiber-liquid phase microextraction for trace enrichment of the residues of atrazine and its major degradation products from environmental water and human urine samples

Abstract

A sample preparation technique using hollow fiber-liquid phase microextraction (HF-LPME) coupled to liquid chromatography has been developed for selective extraction and analysis of atrazine (ATZN) and its major degradation products including desethylatrazine (DEA), desisopropylatrazine (DIA), didealkylatrazine (DDA) and hydroxyatrazine (ATOH) from environmental water and human urine samples. Extraction conditions have been optimized as follows: membrane solvent, di-n-hexylether; acceptor pH, 0.0; donor pH, 7.0; sample volume, 200 mL; extraction time, 5 h; stirring rate, 150 rpm; and ionic strength, in terms of NaCl added, 20% (w/v). The analytical method developed has been validated both in reagent water and environmental water and human urine samples. Trace level detection as well as linearity, with the coefficient of determination (r²) ranging from 0.994 to 0.999, was obtained for the triazine compounds over a wide range of analyte concentrations between 10 and 500 μg L⁻¹, using the peak area as the response variable. The repeatability and reproducibility of the method were less than 11 and 17%, respectively, at a concentration of 50 μg L⁻¹ for each analyte. Limits of detection and quantification ranged from 0.03 to 1.12 μg L⁻¹ and 0.10 to 3.73 μg L⁻¹, respectively, using HPLC with UV detection. This confirms the reliability of the developed technique for further application in trace level enrichment of the residues of the target analytes and other polar, ionizable and structurally related contaminants in environmental water and human urine samples.