Preconcentration and Determination of Trace Amounts of Lead and Cadmium in Food Samples with Ionic Liquid Coated Magnetic Nanoparticles as a New Nano AdsorbentAuthor(s): Elaheh Konoz*, Sara Khodadadi, Ali Ezabadi and Ali Niazi
In the present study, a new, simple and rapid method is developed for pre-concentration and determination of the trace amounts of Pb (II) and Cd (II) ions in food samples through solid phase extraction using (Fe3O4SiO2 (DABCO-PDO) Cl) ionic liquid modified magnetic nanoparticles. This adsorbent was used for the first time to extract and pre-concentrate lead and cadmium metals. Herein, Pb (II) and Cd (II) contents were quantified with Flame Atomic Absorption Spectroscopy (FAAS). The effect of different empirical parameters (such as sample pH, adsorbent amount, type and amount of the solvent, extraction and desorption times and the ligand concentration) was evaluated and optimized for Pb (II) and Cd (II) extraction and pre-concentration. The calibration curve was linear under the optimum condition in the concentration range of 0.8-4.5 µgL-1 with the correlation coefficient of 0.9986. The concentration factor was 100 with the detection limit of 0.25 µgL-1 and 0.068 for Pb and Cd, respectively. The repeatability of Relative Standard Deviations (RSD%) for the concentration of 1 mgL-1 was 1.8 for Pb and 1.4 for Cd. The developed method was successfully used to determine lead and cadmium content in food samples (milk, yogurt, rice, fish, olive oil, sunflower oil). The ionic liquid-modified magnetic nanoparticles were further characterized using Fourier Transform Infrared Spectroscopy (FT-IR) analysis, Scanning Electron Microscopy (SEM), X-Ray Powder Diffraction (XRD), Transmission Electron Microscopy (TEM) and Vibrating Sample Magnetometer (VSM) techniques.