Extraction and Preconcentration of Trace Amounts of Mercury Using Functionalized MagneticNanoparticles Prior to Their Determination by UVVis Spectrophotometry

In this paper, magnetic nanoparticles functionalized by triazene ligand were prepared for extraction/preconcentration of trace amounts of mercury ions in water samples former on its determination with UVVis spectrophotometry. The modified magnetic nanoparticles were characterized by the various techniques such as Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM) and X –Ray Diffractometry (XRD). In the separation process, aqueous solution of Hg2+ ion was mixed with Fe3O4 magnetite nanoparticles modified with (E)1(2Ethoxyphenyl)3(4nitrophenyl)triaze1ene (ENT), (MNPs@SiO2ENT) and then external magnetic field was applied for isolation of magnetite nanoparticles containing mercury ions. Experimental conditions for effective adsorption including pH, ENT amount, Fe3O4 NPs amounts, and eluent type have been studied and established. Under the optimal extraction and preconcentration conditions, calibration curve was linear in the range of 4–80 µgL1 with r2 = 0.9992 (n=20), the limit of detection (LOD) 1.05µg L1 and enrichment factor was 38, respectively. This technique was successfully used for the determination of Hg (II) in aqueous samples.