Quantitative identification of toxic metals in water and food samples using ion imprinted polymer based magnetic graphene oxide

In this paper, a procedure is proposed for the determination of toxic metals in food and water samples simoultaniously employing ion imprinted polymer [1] based magnetic graphene oxide [2]. The polymer has been synthesized by the suspension polymerization technique [3] using azobisisobutyronitrile (AIBN) as a initiator, 1,5-diphenyl carbazone as a chelating agent and methacrylic acid (MAA) and ethylene glycol dimethacryalte (EGDMA) as functional monomer and cross linker respectively. The resulting composites were verified by X-ray diffraction, field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FT-IR). Various analytical parameters such as extraction and desorption time, eluent type and concentration and pH were evaluated. Results shown that the IIP offers imprinting properties for Cu (II), Ni (II), Pb (II), Cd (II), Zn (II) and Mn (II) with analytical recoveries close to 100% for all elements. whiles the non-imprinted polymer (NIP) did not show tendency for any trace element. In addition, the polymer does not interact with alkaline or alkaline-earth metals. The limits of detection of the method for all evaluated heavy metals were between 0.02- 0.20 µg L-1 when Inductively coupled plasma atomic emission spectroscopy ICP-OES [4] was used as a detector. Finally, the proposed analytical procedure was successfully applied to monitoring that metal ions in food and water samples with satisfactory results for the spiked samples.