Tandem dispersive liquid–liquid microextraction coupled with micro-sampling flame atomic absorption spectrometry for rapid determination of lead(II) and cadmium(II) ions in environmental water samples

ABSTRACT

Tandem dispersive liquid liquid microextraction coupled with micro - sampling flame atomic absorption spectrometry for rapid determination of lead2 and cadmium2 ions in environmental water samples. A simple method termed as tandem dispersive liquid–liquid microextraction coupled with micro-sampling flame atomic absorption spectrometry is used for determination of the lead(II) and cadmium(II) ions in different environmental water samples. According to the proposed method, the target analytes are extracted from an aqueous sample solution (10 mL) into a micro-volume of an organic solvent, and then they are selectively back-extracted into an aqueous acceptor solution (150 μL) to increase the compatibility of the extractant phase with a final analyser system and provide a suitable enrichment factor. The developed method is very fast, implemented in just about 7 min, and provides a high sample clean-up. The factors influencing the extraction efficiency including the type and volume of the organic solvent, pH and volume of the acceptor solution, and number of extractions are thoroughly examined and optimised. Under the optimal experimental conditions, the developed method provides a good linearity (in the range of 0.4–300 ng mL^?1 (R² ≥ 0.994)), and low limits of detection (in the range of 0.07–0.31 ng mL^?1). Finally, the method is successfully applied for the direct determination of the understudied analytes in the river, dam, and well water samples.