Single step in-syringe system for ionic liquid based liquid microextraction combined with flame atomic absorption spectrometry for lead determination

Abstract

A simple, novel and quick single step in-syringe system for ionic liquid based liquid microextraction (SSLME) has been presented in this paper. The objective of this study is to present a novel extraction alternative which avoids the centrifugation step, thermal dispersion and usage of hazardous organic solvents. In this procedure, the hydrophobic Pb–dithizone complex was extracted into the fine droplets of 1-butyl-3-methylimidazolium hexafluorophosphate [C₄mim][PF₆] within a syringe including Triton X-114 (TX-114) as dispersant. Several variables including pH of sample, [C₄mim][PF₆] volume, TX-114 volume, ligand concentration, incubation time and diluents nature were considered to be studied. At optimum experimental values of significant variables, detection limit and the enhancement factor were observed to be 0.281 μg L⁻¹ and 82.6, respectively. The repeatability of the proposed method expressed as RSD (n = 5) was 3.51%. The validity of the developed method was checked out by Pb determination in certified reference material (TMDA-54.4 fortified lake water) and the results were found in good agreement with the certified values. The method was applied satisfactorily for the preconcentration of Pb in real samples.