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The aim of this study is to develop an alternative polymeric chelating agent for rapid and selectively removal with high capacity of Fe3+ ions from the gastrointestinal tract for the oral treatment of acute iron poisoning. For this purpose, Fe3+ imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-(l)- glutamic acid) (HEMA-MAGA) nanoparticles synthesized by surfactant free emülsiyon polymerization. Molecular imprinting (MIP) technique is used to enhance the selectivity of nanoparticles. Due to being carboxyl and amide groups on the MAGA monomer, it was chosen as a chelating agent for Fe3+ ions. Before the synthesizing of Fe3+ imprinted polymer, Fe3+ ions were complexed with MAGA and then Fe3+ imprinted nanoparticles were synthesized in the presence of this Fe3+-MAGA complexes. Poly(HEMA-MAGA) nanoparticles were characterized by infrared spectroscopy (FTIR), atomic force microscopy (AFM). Average particle size and size distribution also determined by Zeta sizer. The specific surface area and mead diameter of the Fe3+ imprinted poly(HEMA-MAGA) nanoparticles was 895 m2.g-1 and 95.3 nm, respectively. The maximum Fe3+ ions binding capacity of the poly(HEMA-MAGA) nanoparticles at pH:4.0 were 206.4 mg.g-1 nanoparticles. Fe3+ removal performance of the Fe3+ imprinted poly(HEMA-MAGA) nanoparticles with presence of other ions, optimum medium pH, temperature and equilibrium binding time were also investigated. Fe3+ removal studies were performed in both aqueous solution and intestinal mimicking solution.The results indicate that Fe3+ imprinted poly(HEMA-MAGA) nanoparticles is an alternative chelating agent for the selective Fe3+ ions removal with a short time and very high capacity.

Cryogels with embedded natural adsorbent are new trend of chromatographic media for separation of biomolecules. In this report, experimental determination of immunoglobulin G (IgG) purification by Cu2+-attached pumice particles unified cryogel (Cu2+-PPUC) was performed. For this purpose, after preparation of Cu2+-attached pumice particles, they were unified with 2-hydroxyethyl methacrylate monomers to produce Cu2+-PPUC through polymerization of gel-forming precursors at subzero temperatures. IgG separation experiments were accomplished in a continuous column system. The highest binding capacity (596.8 mg/g) was obtained by working with 0.02 M phosphate buffer at pH 6.0. The chemical analysis of pumice was examined by X-ray fluorescence spectrometer. Scanning electron microscopy was performed to identify the morphology of Cu2+-PPUC. Langmuir adsorption model was best fitted to interaction when compared to Freundlich model. Temkin model was utilized to characterize adsorption, energetically. Purification ability of Cu2+-PPUC for IgG was shown with high selectivity via reducing SDS–PAGE electrophoresis.

Cu(2+) -immobilized magnetic poly(hydroxyethylmethacrylate-N-methacryloyl-(l)-histidinemethylester) (mPHEMAH) nanoparticles were prepared by surfactant-free emulsion polymerization for cytochrome C (cyt C) purification from rat liver. Elemental analysis, atomic force microscopy, zeta sizer, and vibrating sample magnetometer were used to characterize mPHEMAH nanoparticles. In addition to these characterization steps, surface area, average particle size, and size distribution of mPHEMAH nanoparticles were determined. Quantity of immobilized Cu(2+) was measured using atomic absorption spectrophotometry. N-Methacryloyl-(l)-histidinemethylester and Cu(2+) content of mPHEMAH nanoparticles were 0.18 mmol/g polymer and 0.11 mmol/g polymer, respectively. Specific surface area of Cu(2+) -immobilized mPHEMAH nanoparticles was 1180 m(2) /g. Effect of initial cyt C concentration, pH, temperature, and ionic strength on cyt C adsorption onto Cu(2+) -immobilized mPHEMAH nanoparticles was investigated. Maximum cyt C adsorption capacity of Cu(2+) -immobilized mPHEMAH nanoparticles was 311.9 mg/g polymer. Maximum adsorption was obtained at pH 8.0 and 4 °C. Cu(2+) -immobilized mPHEMAH nanoparticles were used ten times with 4.1% decrease in adsorption capacity. In the last stage, Cu(2+) -immobilized mPHEMAH nanoparticles were used to purify cyt C from rat liver tissue, and the purity of desorbed fractions was controlled by SDS-PAGE.

The aim of this study is to label the cells with polymeric nanoparticles properly and efficiently. For this purpose, acridine orange (AO)-loaded poly(2-hydroxyethyl methacrylate) (PHEMA) nanoparticles were synthesized by miniemulsion polymerization. PHEMA nanoparticles were characterized by zeta sizer, zeta potential, atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), fluorescence microscopy, Fourier transform infrared spectrophotometer (FTIR), and elemental analysis. In addition, the toxicity of the nanoparticles were investigated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay.

The aim of this study is to prepare poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine) [PHEMAH] magnetic nanoparticles for plasmid DNA (pDNA) purification from Escherichia coli (E. coli) cell lysate. Magnetic nanoparticles were produced by surfactant free emulsion polymerization. mPHEMAH nanoparticles were characterized by elemental analysis, Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), vibrating sample magnetometer (VSM), electron spin resonance (ESR), thermogravimetric analyses (TGA) and transmission electron microscopy (TEM). Surface area, average particle size and size distribution were also performed. Specific surface area of the mPHEMAH nanoparticles was found to be 1180 m2/g. Elemental analysis of MAH for nitrogen was estimated as 0.18 mmol/g polymer. The amount of pDNA adsorbed onto the mPHEMAH nanoparticles first increased and then reached a saturation value at around 1.0 mg/mL of pDNA concentration. Compared with the mPHEMA nanoparticles (50 μg/g polymer), the pDNA adsorption capacity of the mPHEMAH nanoparticles (154 mg/g polymer) was improved significantly due to the MAH incorporation into the polymeric matrix. The maximum pDNA adsorption was achieved at 25 °C. The overall recovery of pDNA was calculated as 92%. The mPHEMAH nanoparticles could be used six times without decreasing the pDNA adsorption capacity significantly. The results indicate that the PHEMAH nanoparticles promise high selectivity for pDNA.

Metal-chelating affinity beads have attracted increasing interest in recent years for protein purification. In this study, iminodiacetic acid (IDA) was covalently attached to the poly(glycidyl methacrylate) [PGMA] beads (1.6 μm in diameter). Cu(2+) ions were chelated via IDA groups on PGMA beads for affinity binding of hemoglobin (Hb) from human blood hemolysate. The PGMA beads were characterized by scanning electron microscopy (SEM). The PGMA-Cu(2+) beads (628 μmol/g) were used in the Hb binding-elution studies. The effects of Hb concentration, pH and temperature on the binding efficiency of PGMA-Cu(2+) beads were performed in a batch system. Non-specific binding of Hb to PGMA beads in the absence of Cu(2+) ions was very low (0.39 mg/g). The maximum Hb binding was 130.3 mg/g. The equilibrium Hb binding increased with increasing temperature. The negative change in Gibbs free energy (ΔG°0) indicated that the binding of Hb on the PGMA-Cu(2+) beads was a thermodynamically favorable process. The ΔS and ΔH values were 102.2 J/mol K and -2.02 kJ/mol, respectively. Significant amount of the bound Hb (up to 95.8%) was eluted in the elution medium containing 1.0 M NaCl in 1 h. The binding followed Langmuir isotherm model with monolayer binding capacity of 80.3-135.7 mg/g. Consecutive binding-elution experiments showed that the PGMA-Cu(2+) beads can be reused almost without any loss in the Hb binding capacity. To test the efficiency of Hb depletion from blood hemolysate, eluted portion was analyzed by fast protein liquid chromatography. The depletion efficiency for Hb was above 97.5%. This study determined that the PGMA-Cu(2+) beads had a superior binding capacity for Hb compared to the other carriers within this study.

Cibacron Blue F3GA (CB) was covalently attached onto poly(glycidyl methacrylate) (PGMA) monosize beads for removal of bilirubin from hyperbilirubinemia human serum. PGMA beads were produced by dispersion polymerization (1.6 μm in diameter). CB loading was 1.73 mmol/g. Bilirubin adsorption experiments were performed by stirred-batch adsorption. The non-specific adsorption of bilirubin was low (0.4 mg/g polymer). CB attachment onto the PGMA beads significantly increased the bilirubin adsorption (241.5 mg/g) from aqueous solutions. The maximum bilirubin adsorption was observed at pH 6.0. With an increase of the aqueous phase concentration of sodium chloride, the adsorption amount of bilirubin decreased drastically. The equilibrium adsorption of bilirubin significantly increased with increasing temperature. Much higher adsorption values up to 332 mg bilirubin/g were achieved in the case of the PGMA/CB beads from human plasma.

WOS: 000246089000002, PubMed ID: 17222902, The aim of this study is to prepare cholesterol-imprinted polymeric particles. N-Methacryloyl-(L)-tyrosinemethylester (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 FTIR and NMR. Then, cholesterol was complexed with MAT in different mol ratios and the cholesterol-imprinted poly(2-hydroxyethyl methacrylate-N-methacrylOyl-(L)-tyrosine methylester) [MIP] particles were synthesized by bulk polymerization. After that, the template molecules (i.e., cholesterol) were removed using chloroform. MIP particles were characterized by elemental analysis, FTIR, SEM, swelling tests and surface area measurements. Cholesterol adsorption experiments were performed in a batch experimental set-up. Adsorption medium was methanol or intestinal mimicking solution. Stigmasterol and estradiol were used as competing molecules in selectivity tests. Obtained results were as follows: swelling ratio of MIP and non-imprinted (NIP) particles were 60.8% and 44.1% in water. With the increase in the amount of MAT in the polymerization medium, incorporation of MAT was increased (16.6-78.0 mu mol/g). SEM photographs showed the surface roughness and porosity. Specific surface area of NIP and MIP particles were found as 19.2 and 31.5 m(2)/g, respectively. Template molecules (i.e., cholesterol) were removed from the polymer structure in the ratio of 76-84% of the initial concentration. Cholesterol adsorption increased with the increase in cholesterol concentration up to 1.5 mg/mL. MIP particles prepared using higher amounts of cholesterol exhibit significantly higher capacity to the NIP particles (i.e., control polymer). MIP particles were 3.09 and 3.60 times selective with respect to the stigmasterol and estradiol, respectively. Reusability of MIP particles was also investigated. MIP particles showed negligible loss in the cholesterol adsorption capacity after five adsorption-desorption cycles with the same adsorbent

The aim of this study was to prepare Concanavalin A (Con A) immobilized magnetic poly(glycidyl methacrylate) (mPGMA) beads for prostate specific antigen (PSA) binding and to study binding capacities of the beads using lectin-glycoprotein interactions. Firstly, iron oxide nanoparticles were synthesized by co-precipitation method and then, beads were synthesized by dispersion polymerization in the presence of iron oxide nanoparticles. Con A molecules were both covalently immobilized onto the beads directly and through the spacer arm (1,6-diaminohexane-HDMA). The total PSA and free PSA binding onto the mPGMA-HDMA-Con A beads were higher than that of the mPGMA-Con A beads. Maximum PSA binding capacity was observed as 91.2 ng/g. Approximately 45% of the bound PSA was eluted by using 0.1 M mannose as elution agent. The mPGMA-HDMA-Con A beads could be reused without a remarkable decrease in the binding capacities after 5 binding-desorption cycles. Serum fractions were analyzed using SDS-PAGE. The mPGMA-HDMA-Con A beads could be useful for the detection of PSA and suggested as a model system for other glycoprotein biomarkers.

Cu(2+) -immobilized magnetic poly(hydroxyethylmethacrylate-N-methacryloyl-(l)-histidinemethylester) (mPHEMAH) nanoparticles were prepared by surfactant-free emulsion polymerization for cytochrome C (cyt C) purification from rat liver. Elemental analysis, atomic force microscopy, zeta sizer, and vibrating sample magnetometer were used to characterize mPHEMAH nanoparticles. In addition to these characterization steps, surface area, average particle size, and size distribution of mPHEMAH nanoparticles were determined. Quantity of immobilized Cu(2+) was measured using atomic absorption spectrophotometry. N-Methacryloyl-(l)-histidinemethylester and Cu(2+) content of mPHEMAH nanoparticles were 0.18 mmol/g polymer and 0.11 mmol/g polymer, respectively. Specific surface area of Cu(2+) -immobilized mPHEMAH nanoparticles was 1180 m(2) /g. Effect of initial cyt C concentration, pH, temperature, and ionic strength on cyt C adsorption onto Cu(2+) -immobilized mPHEMAH nanoparticles was investigated. Maximum cyt C adsorption capacity of Cu(2+) -immobilized mPHEMAH nanoparticles was 311.9 mg/g polymer. Maximum adsorption was obtained at pH 8.0 and 4 °C. Cu(2+) -immobilized mPHEMAH nanoparticles were used ten times with 4.1% decrease in adsorption capacity. In the last stage, Cu(2+) -immobilized mPHEMAH nanoparticles were used to purify cyt C from rat liver tissue, and the purity of desorbed fractions was controlled by SDS-PAGE.

Interferons are potent biologically active proteins synthesized and secreted by somatic cells of all mammalian species. Dye-affinity adsorption is increasingly used for protein separation. Hollow fibers have several advantages as adsorbents in comparison to conventional bead supports because they are not compressible and they eliminate internal diffusion limitations. The aim of this study was to explore in detail the performance of polyamide hollow fibers to which Cibacron Blue F3GA was attached for adsorption of recombinant interferon-α (rHuIFN-α). The hollow fiber was characterized by scanning electron microscopy. These dye-carrying hollow fibers (35.8 μmol/g) were used in the rHuIFN-α adsorption-elution studies. The effects of initial concentration of rHuIFN-α, medium pH, ionic strength and temperature on the adsorption efficiency of dye-attached hollow fibers were studied in a batch system. The non-specific adsorption of rHuIFN-α on the hollow fibers was 1.2 mg/g. Cibacron Blue F3GA attachment significantly increased the rHuIFN-α adsorption up to 99.8 mg/g. Significant amount of the adsorbed rHuIFN-α (up to 94.8%) was eluted in 1 h in the elution medium containing 1.0 M NaCl. In order to determine the effects of adsorption conditions on possible conformational changes of rHuIFN-α structure, fluorescence spectrophotometry was employed. We resulted that dye-affinity hollow fibers can be applied for rHuIFN-α adsorption without causing any significant conformational changes. Repeated adsorption/elution processes showed that these dye-attached hollow fibers are suitable for rHuIFN-α adsorption.

This study describes the application of an open tubular capillary column for chiral ligand-exchange separation and determination of malic acid enantiomers in apple juice by open-tubular capillary electrochromatography (OT-CEC). The open tubular column was prepared by in-situ grafting polymerization of 3-chloro-2-hydroxypropyl methacrylate (HPMA-Cl) and followed by L-Histidine (L-His) modification. L-His was used as a chiral ligand-exchange selector and copper (II) as a central ion. The electrochromatographic characterization of the open tubular column was performed with the use of thiourea as an electroosmotic flow (EOF) marker. Factors affecting electrochromatographic enantioseparation of malic acid were also studied. The running buffer conditions for optimum enantioseparation of malic acid were found to be ACN/5.0mM CuSO4, 20.0mM (NH4)2SO4 (60/40%, v/v) adjusted to pH 3.0. The separation and determination of the enantiomers of malic acid in the apple juice solution diluted 10- to 40-folds were successfully achieved.

The selective binding of albumin on dye-affinity nanospheres was combined with magnetic properties as an alternative approach for albumin depletion from human plasma. Magnetic poly(hydroxyethyl methacrylate) (mPHEMA) nanospheres were synthesized using mini-emulsion polymerization method in the presence of magnetite powder. The specific surface area of the mPHEMA nanospheres was found to be 1302 m2/g. Subsequent to Cibacron Blue F3GA (CB) immobilization onto mPHEMA nanospheres, a serial characterization processing was implemented. The quantity of immobilized CB was calculated as 800 μmol/g. Ultimately, albumin adsorption performance of the CB-attached mPHEMA nanospheres from both aqueous dissolving medium and human plasma were explored.

The preparation of affinity membranes for application in antibody purification studies is described here. Protein-A-attached poly(hydroxyethyl methacrylate-N-methacryloyl-L-alanine) (PHEMAAL) membranes were produced by a photopolymerization technique and then characterized by swelling tests, surface area measurements, contact angle and scanning electron microscopy (SEM) studies. The water swelling ratio of the PHEMAAL membrane was 133.2%. PHEMAAL membranes have large pores with a size in the range of 5-10 μm. Protein A was covalently attached onto the PHEMAAL membranes via cyanogen bromide (CNBr) activation. Maximum protein A loading was 4.7 mg/g. There was a very low non-specific IgG adsorption onto the PHEMAAL membranes, about 0.38 mg/g. The maximum IgG adsorption on the PHEMAAL-protein A membrane was found to be 9.8 mg/g at pH 7.4 from aqueous solutions. Higher adsorption amount was observed from human plasma (up to 37.3 mg/g). Adsorbed IgG was eluted using 0.1 M glycine-HCl buffer (pH 3.5) with a purity of 93%. PHEMAAL-protein A membrane was used for repetitive adsorption/elution of IgG without noticeable loss in IgG adsorption amount after 10 cycles. The PHEMAAL-protein A membrane showed several advantages, such as simpler preparation procedure, good selectivity for IgG purification from human plasma and good stability throughout repeated adsorption-elution cycles.

Poly(hydroxyethyl methacrylate) (PHEMA) nanoparticles with an average size of 300 nm in diameter and with a polydispersity index of 1.156 were produced by surfactant free emulsion polymerization. Specific surface area of the PHEMA nanoparticles was found to be 996 m(2)/g. Metal-chelating ligand 3-(2-imidazoline-1-yl)propyl(triethoxysilane) (IMEO) was covalently attached to the PHEMA nanoparticles. IMEO content was 0.97 mmol IEMO/g. The morphology and properties of these nanoparticles were characterized with scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy. The Cu2+-chelated PHEMA-IMEO nanoparticles were used in the adsorption-elution studies of human serum albumin (HSA) in a batch system. Maximum HSA adsorption amount of the Cu2+ chelated nanoparticles was 680 mg HSA/g. The PHEMA-IMEO-Cu2+ nanoparticles exhibited a quite high adsorption capacity and fast adsorption rate due to their high specific surface area and the absence of internal diffusion resistance.

The purpose of this study is to observe the structural changes of the thermosensitive poly N-isopropylacrylamide- N-methacryloyl-L-histidine poly NIPA-MAH monolithic cryogel with changing temperature around lower critical solution temperature LCST of NIPA by Small Angle X-Ray Scattering SAXS . Poly NIPA-MAH cryogel was prepared by free radical cryocopolymerization of NIPA with MAH as functional comonomer and N,N- methylene-bisacrylamide MBAAm as crosslinker directly in a plastic syringe. Polymerization initiated by N,N,N,N- tetramethylene diamine TEMED and ammonium persulfate APS pair at subzero temperature in an ice bath. LCST of poly NIPA-MAH cryogel was found to be 34oC. Poly NIPA-MAH cryogel with 60–100 μm in pore diameter have a specific surface area of 42.6 m2/g polymer. This porous cryogel form provides fast temperature response comparing to conventional gels. The surface morphology and bulk structure of poly NIPA-MAH cryogel revealed with scanning electron microscopy SEM . SAXS allowed the determination of nanoalteration of poly NIPA-MAH cryogel such as pore volume, wall thickness and pore shape with changing temperature. Scattering data were analysed both native form and in water at temperature range of 300C-400C. At two different temperatures 34oC and 35oC a detailed investigation on shape of pores and pore size; which indicating a recordable change, were also carried out., B u çalışmanın amacı, NIPA’in düşük kritik çözelti sıcaklığı LCST civarındaki sıcaklığın değiştirilmesiyle ısıya duyarlı poli N-izopropilakrilamid-metakriloil-L-histidin , poli NIPA-MAH monolitik kriyojellerinin nano yapısındaki değişimleri küçük açı x-ışını saçılması SAXS yöntemi ile incelemektir. Poli NIPA-MAH kriyojeller, NIPA, MAH fonksiyonel monomeri ve N,N-metilen-bisakrilamit MBAAm çapraz bağlayıcısı kullanılarak plastik şırınga içerisinde serbest radikal kriyopolimerizasyonu ile hazırlanmıştır. Polimerizasyon buz banyosunda sıfır derecenin altında N, N, N, N-tetrametilen diamin TEMED ve amonyum persulfat APS çifti kullanılarak başlatılmıştır. Poli NIPA-MAH kriyojelinin LCST değeri 34 oC olarak bulunmuştur. Poli NIPA-MAH kriyojelleri 60-100 µm gözenek çapına ve 42.6 m2/g polimer spesifik yüzey alanına sahiptir. Sentezlenen gözenekli kriyojeller geleneksel jellerle karşılaştırıldığında sıcaklık değişimine hızlı tepki vermektedir. Poli NIPA-MAH kriyojelinin yığın yapısı ve yüzey morfolojisi taramalı elektron mikroskobu SEM kullanılarak belirlenmiştir. SAXS, poli NIPA-MAH kriyojelinin sıcaklık değişimiyle gözenek hacmi, duvar kalınlığı ve gözenek şekli gibi nano boyuttaki değişimlerin belirlenmesine imkan vermektedir. 30-40oC sıcaklık aralığında doğal form ve su içerisinde saçılma verileri incelenmiştir. Iki farklı sıcaklıkta 34oC ve 35oC gözenek boyutu ve şekli üzerinde kaydedilebilir bir değişikliği gösteren ayrıntılı bir inceleme de gerçekleştirilmiştir