Mimicking receptor for methylmercury preconcentration based on ion-imprinting

Abstract

Solid-phase extraction (SPE) based on molecularly imprinted polymers (MIPs) were used to develop selective separation and preconcentration for methylmercury ion from complex matrixes. In this study, an ion-imprinting polymer was prepared to make artificial organomercury lyase preorganizing three methacryloyl-(L)-Cysteine methylester (MAC) monomers and one methylmercury ion in a three-coordinate form by template polymerization, with the goal preparing a solid-phase which has the high selectivity for methylmercury ions. Methylmercury-imprinted beads were produced by a dispersion polymerization technique with use methylmercury-methacryloyl-(L)-cysteine (MM-MAC) complex monomer and ethylene glycoldimethacrylate (EDMA). After removal of methylmercury ions, methylmercury-imprinted beads were used for solid-phase extraction and determination of mercury compounds. Methylmercury adsorption and selectivity studies of methylmercury versus other metal ions which Hg(II), Zn(II), Pb(II) and Cd(II) were reported and distribution and selectivity coefficients of these ions with respect to methylmercury were calculated here. ICP-OES and HPLC-DAD determinations of methylmercury and mercury ions in the certified reference, LUTS-1 from the National Research Council of Canada and synthetic sea water showed that the interfering matrix had been almost removed during preconcentration. The methylmercury-imprinted solid-phase as mimic receptor was good enough for methylmercury determination in complex matrixes