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Abstract: In this paper, a l-phenylalanine (l-Phe) imprinted polymer (MIP) based on monodisperse hybrid silica microspheres (MH-SiO2) with ph name="dbnd" />CH2 groups was synthesized by surface imprinting technique. The MH-SiO2 was synthesized by a sol–gel process in aqueous media using tetraethylorthosilicate (TEOS) and 3-methylacryloxypropyl trimethoxysilane (MATES) as the precursors. The morphologies of MH-SiO2 and MIP were characterized with scanning electron microscope (SEM) and the imprinted shell thickness on the surface of MH-SiO2 was calculated as 0.5μm. Compared with the imprinted polymer prepared only by β-cyclodextrin (β-CD) or methacrylic acid (MAA) as functional monomer, the imprinted polymer prepared with both β-CD and MAA as binary functional monomers hold the highest adsorption capacity. Under the optimum chromatographic conditions, a complete baseline separation of phenylalanine racemates was observed only using the column packed with the imprinted polymer prepared with both β-CD and MAA as binary functional monomers. And the separation factor and resolution of the imprinted polymer towards phenylalanine racemates were calculated as 1.41 and 1.46, respectively, which is higher than that of other imprinted polymers. [Copyright &y& Elsevier]

Abstract: A novel magnetic ion-imprinted polymer (Fe3O4@SiO2@IIP) was synthesized by using 3-(2-aminoethylamino)propyltrimethoxysilane (AAPTS) as the functional monomer, tetraethylorthosilicate (TEOS) as the cross-linker and Pb(II) as the template and evaluated for selective extraction of Pb(II) from environmental sample by magnetic solid phase extraction (M-SPE) procedure. The factors affecting separation and preconcentration of the target heavy metals involving pH, eluting solvent and sample volume were studied in detail. Under the optimized experimental conditions, the kinetics adsorption and adsorption capacity of the Fe3O4@SiO2@IIP toward Pb(II) were estimated. The results indicated that the adsorption mechanism is corresponding with the second-order adsorption process with correlation coefficient (r 2 =0.990), and the maximum adsorption capacity is 19.61mgg−1. The relative selectivity factor (β) values of Pb(II)/Cu(II), Pb(II)/Zn(II), Pb(II)/Cd(II) and Pb(II)/Hg(II) are 7.41, 6.76, 3.75 and 6.39, respectively. The Fe3O4@SiO2@IIP was applied for extracting and detecting of Pb(II) in real environmental samples combined with atomic adsorption spectrometer successfully with high recoveries of 98.0%. [Copyright &y& Elsevier]