Magnetic nanoparticles coated with dithizone-modified chitosan for use in solid-phase extraction of copper(ii)

Abstract

A magnetic solid-phase extraction method for detection of trace copper(II) was developed by graphite furnace atomic absorption spectrometry. A novel adsorbent, consisting of magnetic nanoparticles coated with dithizone (DZ)-modified chitosan, was prepared. The adsorbent was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR) and energy dispersive spectrometry (EDS). Effects of pH, amount of adsorbent, adsorption time, elution condition, interference ions and adsorption capacity on the detection of trace copper ion were studied. Under the optimized conditions, the detection limit of the developed method was 0.18 μg L⁻¹ and the adsorption capacity was 210 mg g⁻¹. This adsorbent was successfully applied to the analysis of environmental water samples and certified reference materials.