Hybrid monolith assisted magnetic ion-imprinted polymer extraction coupled with ICP-MS for determination of trace Au(III) in environmental and mineral samples

Abstract In this work, by introducing solvothermal method for generating Fe3O4 nanoparticles and “one-pot” method for synthesizing organic-inorganic hybrid monolithic vinyl functionalized Fe3O4 (Fe3O4@HM), a facile procedure was proposed for preparing poly(1-vinylimidazole) (PVIM) functionalized gold ion imprinted polymer based MNPs@IIP (MNPs@HM@PVIM-Au-IIP). The as-prepared magnetic nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and vibrating sample magnetometry (VSM), etc. After the optimum conditions, including solution pH, adsorption time and sample volume, eluent composition and volume, and elution time were investigated, this MNPs@IIP was employed as ion imprinted polymer magnetic solid phase extraction (II-MSPE) matrix for separation and enrichment of trace gold ions followed by inductively coupled plasma mass spectrometric (ICP-MS) determination with excellent selectivity and sensitivity, and strong anti-interference ability. These merits were benefited from the formation of hybrid monolithic interlayer enduing the resultant MNPs@HM@PVIM-Au-IIP with good chemical and mechanical stability, as well as the dimensional homogeneity due to the solvothermal-generated Fe3O4 nanoparticles as the cores. The applicability superiority of this MNPs@IIP was confirmed by the rapid and efficient extraction of trace level Au(III) in environment water, sediment, soil, coal and ore samples with satisfactory results. The reliability of this II-MSPE-ICP-MS method was also verified by using corresponding Certified Standard Reference materials and spiking recovery of the real samples analyzed.