Preconcentration of Copper and Lead Using Deep Eutectic Solvent Modified Magnetic Nanoparticles and Determination by Inductively Coupled Plasma Optical Emission Spectrometry

In this work, an efficient and eco-friendly magnetic solid-phase extraction method was developed for the simultaneous preconcentration and separation of copper and lead from environmental samples. Deep eutectic solvent modified nano-Fe3O4 particles (Fe3O4-DES) were used as the adsorbent in the MSPE procedure. The analytes were trapped by the adsorbent while stirring and separated from the solution by the action of an external magnetic field. Then, the analytes were eluted from the surface of Fe3O4-DES with HNO3 solution and determined by inductively coupled plasma optical emission spectrometry (ICP-OES). Several factors affecting the extraction efficiency, such as type of DES, pH of the solution, extraction time, amount of the adsorbent, sample volume, and the volume and concentration of the eluent, were investigated. Under the optimal conditions, the detection limits of the proposed method were 0.29 mu g L-1 and 0.51 mu g L-1 for copper and lead respectively, with a relative standard deviation of 3.55% and 2.62%, respectively (n=7). Verification of the accuracy of the method was carried out by analysis of certified reference materials. The method was applied to the determination of trace amounts of copper and lead in environmental samples with satisfactory results.