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We combined the ion-imprinting technique and the binding ability of Fe3ions to organosmectite to create the inorgano-organo Fe3ions imprinted polymer−nanocomposite traps with the goal of preparing a solid phase that has high selectivity for Fe3ions. In the first step, the intercalation of quartamine cations was conducted by an ion-exchange process between the smectite host and an aqueous quartamine solution and Fe3ions were complexed with methacryloylamidoantipyrine (MAAP). In the second step, quartamine cations were exchanged with a preorganized metal−chelate complex monomer for the preparation of polymer nanocomposite traps based on the intersurface ion-imprinting. After that, the template ions (i.e., Fe3) were removed using 4.0 M HNO3solution. Fe3-imprinted nanocomposites were characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), swelling studies, and elemental analysis. Maximum binding capacity, optimum pH, and equilibrium binding time were found to be 78.5 mg/g, pH 3.0, and 10 min, respectively. The relative selectivity coefficients of the imprinted nanocomposite traps for Fe3/Al3, Fe3/Cu2, Fe3/Co2, and Fe3/Zn2were 5.28, 11.4, 15.8, and 72.6 times greater than the nonimprinted nanocomposites, respectively. The Fe3-imprinted nanocomposite traps could be used many times without decreasing in their adsorption capacities significantly. [ABSTRACT FROM AUTHOR]

The aim of this study is to prepare an ion-imprinted monolith which can be utilized to remove Fe 3+from beta thalassemia patient plasma. Fe 3+, as a template, was initially complexed with N-methacryloyl-( l)-cysteine methyl ester (MAC) to form MAC−Fe 3+(the complex monomer), which was then polymerized with hydroxyethyl methacrylate (HEMA) to constitude a Fe 3+-imprinted poly(HEMA−MAC) monolith (PHEMAC−Fe 3+) by bulk polymerization method. The template (Fe 3+) was removed from the polymer by 0.1 M EDTA solution. The specific surface area of PHEMAC−Fe 3+was found to be 35.2 m 2/g with a swelling ratio of 60.2%. A maximum adsorption capacity of 150 μg Fe 3+/g was observed with PHEMAC−Fe 3+. It was determined that PHEMAC−Fe 3+possesses relative selectivity coefficients for Fe 3+/Cd 2+and Fe 3+/Ni 2+, which are 42.6 and 36.1, respectively, times greater than nonimprinted monolith (produced in the absence of Fe 3+, PHEMAC). The PHEMAC−Fe 3+monolith has been recovered and reused many times without a significant decrease in its adsorption capacity. [ABSTRACT FROM AUTHOR]

Iminodiacetic acid (IDA)-functionalized adsorbents have attracted increasing interest in recent years for immobilized metal-affinity chromatography (IMAC). In this study, IDA was covalently attached to nonporous monosize poly(glycidyl methacrylate) poly(GMA) beads (1.6 m in diameter). Cu2ions were chelated via IDA groups for affinity depletion of immunoglobulin G (IgG) from human serum. The monosize poly(GMA) beads were characterized by scanning electron microscopy. The Cu2-chelated beads (628 mol/g) were used in the IgG adsorption−elution studies. Studies to determine the effects of IgG concentration, pH, and temperature on the adsorption efficiency of Cu2-chelated beads were performed in a batch system. Nonspecific binding of IgG to monosize beads in the absence of Cu2ions was very low (0.45 mg/g). The IgG adsorption to chelated Cu2ions was 171.2 mg/g. The equilibrium IgG adsorption increased with increasing temperature. The negative change in Gibbs free energy (Go< 0) indicated that the adsorption of IgG on the Cu2-chelated beads was a thermodynamically favorable process. The Sand Hvalues were 172.1 J/mol·K and −43.2 kJ/mol, respectively. A significant amount of the adsorbed IgG (up to 97.2%) was eluted in the elution medium containing 1.0 M NaCl in 1 h. The kinetics of the interactions suggest that the interactions could be best represented by a mechanism based on second-order kinetics (k9.8 × 10-5to 118.9 × 10-5g·mg-1·min-1). The adsorption followed the Langmuir isotherm model with monolayer adsorption capacity of 156.2−212.8 mg/g. Consecutive adsorption−elution experiments showed that the Cu2-chelated beads can be reused almost without any loss in the IgG adsorption capacity. To test the efficiency of IgG depletion from human serum, proteins in the serum and eluted portion were analyzed by two-dimensional gel electrophoresis. The depletion efficiency for IgG was above 98.2%. Eluted proteins include mainly IgG and a negligible amount of non-albumin proteins such as apo-lipoprotein A1, sero-transferrin, haptoglobulin, and 1-antitrypsin. When anti-HSA-Sepharose adsorbent is used together with our metal-chelated monosize poly(GMA) beads, IgG and HSA can be depleted in a single step. [ABSTRACT FROM AUTHOR]

The objective of this study is to prepare bilirubin-imprinted polymeric particles for the selective removal of bilirubin from hyperbilirubinemic human plasma. N-methacryloyl-(l)-tyrosine methylester (MAT) was chosen as the complexing monomer. In the first step, functional monomer MAT was synthesized by the reaction of l-tyrosine methylester and methacryloyl chloride and characterized by nuclear magnetic resonance (NMR). Bilirubin then was complexed with MAT and the bilirubin-imprinted poly(2-hydroxyethyl methacrylate-N-methacryloyl-(l)-tyrosine methylester) MIP was produced by bulk polymerization. The template molecules (i.e., bilirubin) then were removed using sodium carbonate and sodium hydroxide. MIP particles were characterized by elemental analysis, water uptake tests, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). Bilirubin adsorption experiments from human plasma were performed in a batch experimental setup. Cholesterol and testosterone were used as competing molecules in selectivity tests. Obtained results were as follows:  the water uptake ratio of MIP and non-imprinted (NIP) particles were 64.7% and 51.3%, respectively, in water. According to the elemental analysis results, the incorporation of MAT was 69.0 mol/g for MIP particles. SEM micrographs showed the surface roughness and porosity. The specific surface area of the MIP particles was determined to be 27.8 m2/g. The pore diameter of the MIP particles varied over a range of 20−245 Å and the average pore diameter was 25.0 Å. Template molecules (i.e., bilirubin) were removed from the polymer structure in the ratio of 87% of the initial concentration. Bilirubin adsorption increased as the bilirubin concentration increased, up to 0.8 mg/mL. The maximum bilirubin adsorption capacity was 3.4 mg/g of the dry weight of particles. MIP particles were 6.3 and 3.0 times more selective, with respect to the cholesterol and testosterone, respectively. Reusability of the MIP particles was also investigated. MIP particles showed a negligible loss in the bilirubin adsorption capacity after five adsorption−desorption cycles with the same adsorbent. [ABSTRACT FROM AUTHOR]