Ultrasound-assisted temperature-controlled ionic liquid microextraction for the preconcentration and determination of cadmium content in mussel samples

Abstract

In this paper, we propose a simple and quick method for the preconcentration of cadmium in mussels (Mytella guyanensis) using ultrasound-assisted temperature-controlled ionic liquid microextraction, which is subsequently detected by flame atomic absorption spectrometry (FAAS). The ionic liquid (IL) 1-hexyl-3-methylimidazolium hexafluorophosphate [Hmim][PF6] and 2-(2'-benzotiazolilazo)-p-cresol (BTAC) were used as the extraction solvent and chelating agent, respectively. An investigation of the variables that influence the preconcentration, such as pH, temperature, sonication time, amount of reagents and cooling time, was carried out. After optimization of these variables, the developed method yielded a preconcentration factor of 40, precision of 1.5% (5.0 μg L−1), and limit of detection of 0.10 μg L−1. The accuracy of the method was evaluated by an analysis of the following certified reference materials: mussel tissue (ERM-CE 278), aquatic plant (Lagarosiphon major, BCR-060), and plankton (BCR-414). The procedure was then applied for the determination of Cd in mussel samples, which was found to vary from 0.837 to 1.150 μg g−1. The reported method is simple, fast, efficient, and easy to perform, and represents an interesting alternative for the determination of cadmium.