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The aim of this study was to investigate the heavy metal adsorption performance of supermacroporous polyhydroxyethyl methacrylate PHEMA cryogel. The PHEMA cryogel was produced by cryopolymerization. The PHEMA cryogel was characterized by scanning electron microscopy SEM. The PHEMA cryogel containing 385 μmol Reactive Green HE4BDg were used in the adsorption studies. Adsorption capacity of the PHEMA cryogel for the metal ions, i.e., Cu2, Cd2, and Pb2were investigated in aqueous media containing different amounts of the ions 5–600 mgL and at different pH values 3.2–6.9. The maximum adsorption capacities of the PHEMA cryogel were 11.6 mgg 56 μmolg for Pb2, 24.5 mgg 385 μmolg for Cu2and 29.1 mgg 256 μmolg for Cd2. The competitive adsorption capacities were 10.9 mgg 52 μmolg for Pb2, 22.1 mgg for Cd2196 μmolg and 23.2 mgg 365 μmolg for Cu2. The PHEMAReactive Green HE4BD cryogel exhibited the following metal ion affinity sequence on molar basis: Cu2> Cd2> Pb2. The PHEMAReactive Green HE4BD cryogel can be easily regenerated by 50 mMEDTA with higher effectiveness. These features make the PHEMAReactive Green HE4BD cryogel a potential adsorbent for heavy metal removal. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [ABSTRACT FROM AUTHOR]

Ni2imprinted monolithic column was prepared for the removal of nickel ions from aqueous solutions. NMethacryloylLhistidine was used as a complexing monomer for Ni2ions in the preparation of the Ni2imprinted monolithic column. The Ni2imprinted polyhydroxyethyl methacrylateNmethacryloylLhistidine PHEMAH monolithic column was synthesized by bulk polymerization. The template ion Ni2 was removed with a 42pyridylazo resorcinol PAR:NH3NH4Cl solution. The wateruptake ratio of the PHEMAH–Ni2monolith increased compared with PHEMAH because of the formation of nickelion cavities in the polymer structure. The adsorption of Ni2ions on both the PHEMAH–Ni2and PHEMAH monoliths were studied. The maximum adsorption capacity was 0.211 mgg for the PHEMAH–Ni2monolith. Fe3, Cu2, and Zn2ions were used as competitive species in the selectivity experiments. The PHEMAH–Ni2monolithic column was 268.8, 25.5, and 10.4 times more selective than the PHEMAH monolithic column for the Zn2, Cu2, and Fe3ions, respectively. The PHEMAH–Ni2monolithic column could be used repeatedly without a decrease in the Ni2adsorption capacity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [ABSTRACT FROM AUTHOR]

Magnetic poly(ethylene glycol dimethacrylate‐N‐methacryloyl‐(L)‐histidine methyl ester) [m‐poly(EGDMA‐MAH)] beads were prepared by suspension polymerization for the affinity depletion of immunoglobulin‐G (IgG) from human serum in a batch system. Elemental analysis of the magnetic beads for nitrogen was estimated as 70 μmol MAH/g polymer. IgG adsorption onto the m‐poly(EGDMA) was negligible. Higher adsorption value (up to 46.8 mg/g) was obtained in which the m‐poly(EGDMA‐MAH) beads were used. IgG adsorption capacity of the magnetic beads increased with an increase in the concentration of IgG. The maximum IgG adsorption was observed at pH 6.5 for MOPS buffer. IgG molecules could be repeatedly adsorbed and eluted with these adsorbents, without noticeable loss in their IgG adsorption capacity. Adsorption capacity decreased for both increasing salt concentration and temperature. In this study, we show that m‐poly(EGDMA‐MAH) beads (wherein IgG molecules bind directly with the matrix) can be used directly for affinity depletion without further modification. Higher adsorption value was obtained from human serum (up to 85.7 mg/g). The elution results demonstrated that the adsorption of IgG to the adsorbent was reversible. The depletion efficiencies for IgG were above 85% for all studied concentrations. Eluted portion was analyzed for testing the IgG removal efficiency by two dimensional gel electrophoresis. Eluted proteins include mainly IgG, and a small number of nonalbumin proteins such as apolipoprotein A1, serotransferrin, haptoglobulin, and α1‐antitrypsin. IgA was not identified in eluted fraction. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [ABSTRACT FROM AUTHOR]

The magnetic poly(2-hydroxyethyl methacrylate ethylene glycol dimethacrylate) m-poly(HEMA-EGDMA) beads (150−250-m diameter in spherical form) were prepared by a radical suspension polymerization technique. The pseudo-specific ligand, reactive imidazole containing 3-(2-imidazoline-1-yl)propyl (triethoxysilane) (IMEO) was selected as a silanization agent. IMEO was covalently immobilized onto the magnetic beads. IMEO-immobilized m-poly(HEMA-EGDMA) beads were used for the affinity adsorption of immunoglobulin-G (IgG) from aqueous solutions and human plasma. To evaluate the degree of IMEO attachment, the m-poly(HEMA-EGDMA) beads were subjected to Si analysis by using flame atomizer atomic absorption spectrometer, and it was estimated as 36.6 mg IMEO/g of polymer. The nonspecific IgG adsorption onto the plain m-poly(HEMA-EGDMA) beads was very low (about 0.4 mg/g). Higher adsorption values (up to 55 mg/g) were obtained when the m-poly(HEMA-EGDMA)/IMEO beads were used from both aqueous solutions and human plasma. The maximum IgG adsorption on the m-poly(HEMA-EGDMA)-IMEO beads was observed at pH 7.0. The IgG molecules could be repeatedly adsorbed and desorbed with m-poly(HEMA-EGDMA)-IMEO beads without noticeable loss in the IgG adsorption capacity. The adsorption capacity from human plasma in magnetically stabilized fluidized bed decreased drastically from 78.9 to 19.6 mg/g with the increase of the flow rate from 0.2 to 3.5 mL/min. [ABSTRACT FROM AUTHOR]

Poly(acrylamide‐allyl glycidyl ether) [poly(AAm‐AGE)] cryogel was prepared by bulk polymerization which proceeds in an aqueous solution of monomers frozen inside a glass column (cryo‐polymerization). After thawing, the monolithic cryogel contains a continuous polymeric matrix having interconnected pores of 10–100 μm size. Cibacron Blue F3GA was immobilized by covalent binding onto poly(AAm‐AGE) cryogel via epoxy groups. Poly(AAm‐AGE) cryogel was characterized by swelling studies, FTIR, scanning electron microscopy, and elemental analysis. The equilibrium swelling degree of the poly(AAm‐AGE) monolithic cryogel was 6.84 g H2O/g cryogel. Poly(AAm‐AGE) cryogel containing 68.9 μmol Cibacron Blue F3GA/g was used in the adsorption/desorption of human serum albumin (HSA) from aqueous solutions and human plasma. The nonspecific adsorption of HSA was very low (0.2 mg/g). The maximum amount of HSA adsorption from aqueous solution in acetate buffer was 27 mg/g at pH 5.0. Higher HSA adsorption value was obtained from human plasma (up to 74.2 mg/g). Desorption of HSA with a purity of 92% from Cibacron Blue F3GA attached poly(AAm‐AGE) cryogel was achieved using 0.1M Tris/HCl buffer containing 0.5M NaCl. It was observed that HSA could be repeatedly adsorbed and desorbed with poly(AAm‐AGE) cryogel without significant loss in the adsorption capacity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [ABSTRACT FROM AUTHOR]

Porous polymeric beads were obtained by the suspension polymerization of 2‐hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA). Poly(HEMA–EGDMA) beads were characterized by surfacearea measurements, swelling studies, FTIR, scanning electron microscopy (SEM), and elemental analysis. Poly (HEMA–EGDMA) beads had a specific surface area of 56 m2/g. SEM observations showed that the poly(HEMA–EGDMA) beads abounded macropores. Poly(HEMA–EGDMA) beads with a swelling ratio of 55%, and containing different amounts of Reactive Red 120 (9.2–39.8 μmol/g) were used in the adsorption/desorption of human serum albumin (HSA) from aqueous solutions and human plasma. The nonspecific adsorption of HSA was very low (0.2 mg/g). The maximum HSA adsorption amount from aqueous solution in phosphate buffer was 60.1 mg/g at pH 5.0. Higher HSA adsorption value was obtained from human plasma (up to 95.7 mg/g) with a purity of 88%. The equilibrium monolayer adsorption amount, Qmax was determined as 172.4 mg/g. The dimensionless separation factor (RL) value shows that the adsorption behavior of HSA onto the Reactive Red 120 attached poly(HEMA–EGDMA) beads was favorable (0 < RL < 1). Desorption of HSA from Reactive Red 120 attached poly (HEMA–EGDMA) beads was performed using 0.1M Tris/HCl buffer containing 0.5M NaCl. It was observed that HSA could be repeatedly adsorbed and desorbed with Reactive Red 120‐attached poly(HEMA–EGDMA) beads without significant loss in the adsorption amount. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [ABSTRACT FROM AUTHOR]

Monosize, nonporous poly(glycidyl methacrylate) [poly(GMA)] beads were prepared by dispersion polymerization. Cibacron Blue F3GA was covalently attached onto the poly(GMA) beads for adsorption of recombinant interferon‐α (rHuIFN‐α). Monosize poly(GMA) beads were characterized by scanning electron microscopy. Dye‐carrying beads (1.73 mmol/g) were used in the adsorption–elution studies. The effect of initial concentration of rHuIFN‐α, pH, ionic strength, and temperature on the adsorption efficiency was studied in a batch system. Nonspecific adsorption of rHuIFN‐α on the beads was 0.78 mg/g. Dye attachment significantly increased the rHuIFN‐α adsorption up to 181.7 mg/g. Equilibrium adsorption of rHuIFN‐α onto the dye‐carrying beads increased with increasing temperature. Negative change in free energy (ΔG0 < 0) indicated that the adsorption was a thermodynamically favorable process. ΔS and ΔH values were 146.1 J/mol K and −37.39 kJ/mol, respectively. Significant amount of the adsorbed rHuIFN‐α (up to 97.2%) was eluted in the elution medium containing 1.0M NaCl in 1 h. To determine the effects of adsorption conditions on possible conformational changes of rHuIFN‐α structure, fluorescence spectrophotometry was employed. We concluded that dye‐affinity beads can be applied for rHuIFN‐α adsorption without causing any significant conformational changes. Repeated adsorption–elution processes showed that these beads are suitable for rHuIFN‐α adsorption. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 975–981, 2007 [ABSTRACT FROM AUTHOR]