Supramolecular solvent-based microextraction of copper and lead in water samples prior to reacting with synthesized Schiff base by flame atomic absorption spectrometry determination

Abstract

A supramolecular solvent made up of reverse micelles of nonanoic acid, dispersed in a continuous phase of tetrahydrofuran (THF) and water, is proposed for the simple, rapid and efficient microextraction of copper (Cu) and lead (Pb) in water samples prior to flame atomic absorption spectrometry determination. A new Schiff base was synthesized and used as the chelating agent in this study. Some important extraction parameters such as the pH, Schiff base concentration, the composition and volume of the supramolecular solvent and vortex time are evaluated, obtaining the most favorable results. Under the optimized conditions, the calibration curves were linear in the range of 10–800 μg L⁻¹ for Cu and 10–500 μg L⁻¹ for Pb, respectively. The limits of detection (LOD) were 0.29 μg L⁻¹ and 0.45 μg L⁻¹, with the enrichment factors of 27 and 22 for Cu and Pb, respectively. Recoveries of Cu and Pb spiked in water samples were in the range of 91.2–102.1%. The results show that the proposed method is suitable for the determination of Cu and Pb in water samples.