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Gelatin and N-methacryloyl-(L)-histidine methyl ester [MAH] containing poly(2-hydroxyethyl methacrylate) [PHEMA] based cryogels were prepared to aid in enhancing cell proliferation. In order to evaluate effects of MAH comonomer and gelatin, cryogels were prepared containing different amounts of gelatin and MAH. Accordingly, four different groups of cryogels which were PHEMA, poly(2-hydroxyethyl methacrylate)-gelatin [PHEMA/GEL], poly(2-hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methyl ester) [PHEMAH] and poly(2-hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methyl ester)-gelatin [PHEMAH/GEL] were prepared and a total of eight cryogel groups were obtained depending on the varying gelatin ratios. Swelling tests, scanning electron microscope (SEM), microcomputed tomography (Micro-CT) and Fourier transform infrared spectroscopy- Attenuated Total Reflectance (FTIR-ATR) were performed for characterization studies. FTIR-ATR studies confirmed that gelatin and MAH were incorporated into the cryogel structures. Average pore size of cryogels was in the range of 18−198 μm confirmed by Micro-CT and SEM analysis. Then, cryogels were evaluated for cell proliferation abilities by MTT analysis for 24 h and 48 h for cell viability in L929 mouse fibroblast cells. Cell viability of PHEMAH/0.2GEL cryogels reached 209 %. Interaction and proliferation of fibroblast cells on cryogels demonstrated by SEM examination.

Iron (Fe) is an essential mineral, but iron overload can reason in multiple organ failures and cell injury. Iron overload syndromes can be widely classified as hereditary hemochromatosis. The development of iron overload is seen in hereditary hemochromatosis, a common inherited disorder that may lead to progressive organ dysfunction including cirrhosis, arthritis, hypogonadism, diabetes mellitus, and cardiomyopathy. If patients with iron overload are not treated, their life expectancy will be shortened. Nanochelators are usually utilized to remove overload iron. Many novel nanochelator have been formulated for effective methods. The ion molecular imprinting is a technique to form recognition sites in the highly cross-linked polymer using a template ion. In this research, effective ion-imprinted polymer-based nanoparticles were synthesized and evaluated for selective removal of iron(III). The iron-imprinted nanoparticles were prepared by using functional monomer N-methacryloyl-l-glutamic acid (MAGA) and comonomer 2-hydroxyethyl methacrylate by mini-emulsion polymerization techniques. The template analyte was desorbed with 0.01 M EDTA desorption agent. The iron-imprinted nanoparticles were selective for Fe(III) toward other analogs (Zn(II), Cr(III) and Al(III)). The adsorption isotherm model fitted the Langmuir isotherm with 0.995 of R2 value and the 83.33 mg/g of Qmax value for the Fe(III)-imprinted nanoparticles. The values of separation factor (RL) were found to be 0.016 for Fe(III). The maximum binding capacity for the ion-imprinted nanoparticles was found to be 77.80 mg/g dry nanoparticles, which is 8.9 times higher than the non-imprinted nanoparticles under the same conditions. Synthetic gastric fluid experiments were also performed for Fe(III) removal.

In this study, amino acid functionalized poly(2-hydroxyethyl methacrylate-N-methacrylolyl-l-phenylalanine) [PHEMAPA] cryogel discs were prepared. In this respect, phenylalanine containing N-methacryloyl-(L)-phenylalanine methyl ester (MAPA) was polymerized with 2-hydroxyethyl methacrylate (HEMA) without requirement of any activation step. Laccase bound poly(2-hydroxyethyl methacrylate-N-methacryloyl-l-phenylalanine) [Lac-PHEMAPA] cryogel discs were applied for decolorization of Reactive Blue-247 (RB-247). The ability of Lac-PHEMAPA cryogel discs on dye decolorization was found to be as 90% in 2 h and even more within 4h. The decolorization activities of 86% and 73% were observed at relatively low (4°C) and high (60°C) temperatures, respectively. The effect of dye concentration on dye decolorization and 100% decolorization activity was achieved in dye concentration between 50-300 ppm. Lac-PHEMAPA cryogel discs maintained 80% of its decolorization activity after six cycles. Consequently, the PHEMAPA cryogel discs are promising materials for immobilizing laccase. The Lac-PHEMAPA has a rapid dye decolorization in a broad range of temperature. The preparation is furthermore very stable and activity is preserved during storage.

In this study, we fabricated magnetic ion-imprinted polymers (IIP) for arsenic removal. Ion-imprinted method was developed by complexing N-methacryloyl-l-cysteine (MAC) monomer and As(III) and As(V...

In this study, a selective, rapid and sensitive surface plasmon resonance (SPR) sensor is prepared for real time detection of tartrazine in fruit juice. Tartrazine imprinted and non-imprinted poly(hydroxyethylmethacrylate-N-methacryloyl-(L)-histidine methyl ester) thin films are synthesized onto SPR chip surface using ultraviolet polymerization. The characterization studies of tartrazine imprinted and non-imprinted SPR sensors are performed with contact angle measurements, atomic force microscopy and ellipsometry. Then, kinetic studies for tartrazine are carried out in the concentration range of 0.5–100.0 $\mu \text{M}$ . The response time for adsorption, desorption and regeneration cycles is approximately about 15 min for the optical sensor system. The limit of detection and quantification are obtained as $0.0076~\mu \text{M}$ and $0.0252~\mu \text{M}$ , respectively. The selectivity studies of the tartrazine imprinted and non-imprinted SPR sensors are determined in the presence of allura red and sunset yellow molecules. In order to demonstrate the applicability, validation studies of tartrazine imprinted SPR sensor are performed by liquid chromatography-tandem mass spectrometry (LC-MS).

In this study, selective and sensitive detection of the neurotransmitter dopamine (DA) in both aqueous solution and biological samples was performed using a surface plasmon resonance (SPR) sensor based on a molecular imprinting technique. For this, dopamine-imprinted poly(2-hydroxyethyl methacrylate-N-methacroyl-(L)-cysteine methyl ester-gold nanoparticles-N-methacryloyl-L-phenylalanine methyl ester) [PHEMAC-AuNPs/MAPADA] nanoparticles were prepared. Furthermore, to evaluate the imprinting efficiency, non-imprinted [PHEMAC-AuNPs/MAPA] nanoparticles were designed using the same polymerization procedure except for the addition of dopamine molecules. To examine the effect of incorporating AuNPs to increase the SPR signal response, control experiments were carried out via the SPR biosensor produced using [PHEMAC/MAPADA] nanoparticles prepared without the addition of AuNPs. Characterization studies of dopamine- + imprinted [PHEMAC-AuNPs/MAPADA] and non-imprinted [PHEMAC-AuNPs/MAPA] nanoparticles was performed with a zetasizer and an FTIR-ATR spectrophotometer. In addition, dopamine-imprinted [PHEMAC-AuNPs/MAPADA] and non-imprinted [PHEMAC-AuNPs/MAPADA] SPR sensors were characterized by ellipsometer and contact angle measurements. The high imprinting efficiency (I.F: 9.67) of the dopamine-imprinted [PHEMAC-AuNPs/MAPADA] SPR sensor was determined by comparing it with the non-imprinted [PHEMAC-AuNPs/MAPA] SPR sensor. A good linear relationship was obtained in the 0.01–0.5 ppb concentration range with correlation coefficients of 0.9818 and 0.9819, respectively. The dopamine-imprinted [PHEMAC-AuNPs/MAPADA] SPR sensor was 5.53 and 4.59 times more selective for the target molecule dopamine than for epinephrine (EP) and norepinephrine (NE), respectively. The repeatability of the [PHEMAC-AuNPs/MAPADA] SPR sensor was assessed with a 0.5 ppb dopamine solution, with the percent relative standard deviation of the intra-assays (RSD) being less than 1.7%, indicating negligible loss of dopamine sensing capability after four adsorption–desorption cycles with the same sensor.

In the study, magnetic poly(hydroxyethylmethacrylate-N-methacryloyl-(L)-histidine) (mPHEMAH) nanoparticles were prepared by miniemulsion polymerisation using N-methacryloyl-(L)-histidinemethylester...

In this study, quartz crystal microbalance sensors based on molecular imprinting technology were fabricated for real-time detection of insulin in aqueous solution and artificial plasma. This study describes the preparation of insulin imprinted poly(hydroxyethyl methacrylate)-N-methacryloyl-( l )-histidine methyl ester based quartz crystal microbalance sensor for insulin determination. Poly(hydroxyethyl methacrylate)-N-methacryloyl-( l )-histidine methyl ester based film on chip surface was synthesized by ultra violet (UV) polymerization for the detection of insulin at low concentrations. At the first step, N-methacryloyl-( l )-histidine methyl ester complex was formed with insulin and then, the insulin imprinted film has been prepared. The characterization of the polymeric film has been conducted with ellipsometry, contact angle, Fourier transform infrared-attenuated total reflectance and atomic force microscopy measurements. Langmuir, Freundlich and Langmuir-Freundlich adsorption isotherm models were applied for this system. The best fitted model to explain the interactions between molecular imprinted chip and insulin molecules was the Langmuir adsorption isotherm (R2: 0.999). The repeatability of insulin imprinted chip was investigated by using of equilibration-binding-regeneration cycles for four times. The detection limit was found as 0.00158 ng/mL. According to the results, the QCM sensor has showed low-detection limit, high selectivity and sensitivity for insulin assay.

Staphylococcus aureus, Enterococcus faecalis and Escherichia coli are the common causes of wound infections. For the treatment of these infections, ciprofloxacin can be recommended as a broad-spectrum antibiotic that acts on both Gram-negative and Gram-positive microorganisms. Besides, antimicrobial agents could be integrated into polymeric materials. Cryogels, one of these polymeric materials, are spongy polymers showing high macroporosity. In addition to their attractive usage as affinity support materials and scaffolds, they also appear as drug carrier materials in recent years. Molecular imprinting method is a recognition technique prepared by forming a polymeric network around the template. Although this method has been used in purification and separation processes for more than thirty years, it has gained great interest as a new approach that provides an advantage in drug release studies in terms of high drug loading capacity and long-term release. In this study, ciprofloxacin (CIP) imprinted 2-Hydroxyethyl methacrylate (HEMA) based N-methacryloyl-(L)-histidine methyl ester (MAH) containing [CIP-p(HEMAH)] cryogels was prepared and characterized. CIP releasing experiments were performed, and then, antimicrobial activities of CIP p(HEMAH) cryogels were examined against S. aureus, E. faecalis and E. coli. It can be concluded that CIP-p(HEMAH) cryogels could be proposed as promising polymeric materials for wound healing applications.

The development of novel biocompatible and cost effective cryogel membrane which shows enhanced antimicrobial properties in order to use for several approaches such as wound dressing, scaffold or food packaging was aimed in this study. A super macro porous lysozyme imprinted cryogel membranes showing antibacterial effect against both Gram-positive and Gram-negative bacteria were prepared by using molecular imprinting technique. N-methacryloyl-(L)-histidine methyl ester (MAH) was used as the pseudo specific ligand and complexed with Cu++ in order to provide metal ion coordination between MAH and template molecule (lysozyme). Comparing the antibacterial activity of different lysozyme concentrations, cryogel membranes were prepared in three different concentrations. To synthesize Poly (hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methylester) P(HEMA-MAH) cryogel membrane, free radical polymerization initiated by N, N, N', N'-tetramethylene diamine (TEMED) and ammonium persulfate (APS) was carried out at -12 °C. The characterization of the lysozyme imprinted cryogel membrane was accomplished by using scanning electron microscopy (SEM), swelling degree measurements and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) spectroscopy. The cytotoxicity test of produced membrane was performed by using mouse fibroblast cell line L929. The antibacterial activity of P(HEMA-MAH) lysozyme molecular imprinted [P(HEMA-MAH) Lyz-MIP] cryogel membranes against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were determined by Kirby-Bauer membranes diffusion and viable cell counting methods. When the antibacterial effect of P(HEMA-MAH) Lyz-MIP cryogel membranes were evaluated, it was found that P(HEMA-MAH) Lyz-MIP cryogel membranes had stronger antibacterial effects against Gram-negative E. coli bacteria even in low lysozyme concentrations. In addition, 100% bacterial inhibition was detected for both of two bacteria at increasing lysozyme concentrations.

Antibacterial micron-sized cryogels, so-called microcryogels, were prepared by cryogelation of gelatin and integration of lysozyme. Gelation yield, specific surface area, macro-porosity and swelling degree of the microcryogels were examined in order to characterize their physical properties. MTT method was utilized to measure cell viability of the gelatin microcryogels with a period of 24, 48, and 72 h and no significant decrease was observed at 72 h. Apoptotic staining assay also showed high viability at 24, 48, 72 h in parallel with the control group. The antibacterial performances of the gelatin microcryogels against

Human body is greatly exposed to aluminum due to its high abundance in the environment. This nonessential metal is a threat to the patients of chronic renal disorders, as it is easily retained in their plasma and quickly accumulates in different tissues. Thus, there is great need to remove it from the aqueous environment. In this study, Al3+ imprinted semiinterpenetrating polymer network (semi-IPN)-based cryogel composite was prepared and applied for the purification of environmental and drinking water samples from aluminum. Poly (2-hydroxyethyl methacrylate) (pHEMA) discs were produced via cryogenic treatment and imprinted semi-IPN was introduced to the 3-(trimethoxysilyl) propyl acrylate-modified macroporous cryogel discs. The adsorption properties and selectivity of the aluminum (III) imprinted semi-IPN cryogel composite were studied in detail. The imprinted semi-IPN cryogel composite showed good selectivity towards aluminum (III) ions with the imprinting factor (IF) of 76.4 in the presence of competing copper (II), nickle (II), and iron (III) ions. The maximum adsorption capacity of 271 mu mol g(-1) was obtained for aluminum (III) at pH 7.0 within 10 min using imprinted semi-IPN cryogel composite. The good selectivity and reusability of aluminum (III)-imprinted semi-IPN cryogel composite makes this material an eligible candidate for the purification of drinking water from aluminum (III) leaving important minerals remained in the water.

In this study was prepared Cd(II)) ion-imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-cysteine methylester) pHEMAC nanoparticles for the oral treatment of heavy metal poisoning. Cd(II) ion-imprinted pHEMAC nanoparticles were characterized by TEM, FTIR, zetasizer, and surface area calculations. The efficiency and selectivity of these Cd(II) ion imprinted pHEMAC nanoparticles were investigated both in deionized water and simulated gastrointestinal fluids. Adsorption studies were performed at different pH, temperature and initial concentrations of Cd(II) ion to determine optimum conditions. The selectivity studies were accomplished with Cd(II) ion imprinted and non-imprinted pHEMAC nanoparticles by using different metal ion solutions (i.e., copper, zinc, nickel, and lead). Langmuir and Freundlich isotherms were applied for these adsorption studies

In this study, we have reported a novel fabrication technique for human serum albumin (HSA) imprinted composite bacterial cellulose nanofibers (MIP-cBCNFs) used for the depletion of HSA selectively from artificial blood plasma for proteomic applications. Molecular imprinting was achieved by using metal ion coordination interactions of N?methacryloyl?(L)?histidinemethylester (MAH) monomer and Cu(II) ions. MAH-Cu(II)-HSA complex was polymerized with bacterial cellulose nanofibers (BCNFs) under constant stirring at room temperature. The characterization of the MIP-cBCNFs was carried out by FTIR-ATR, SEM, contact angle measurements and surface area measurements. The adsorption experiments of HSA onto the MIP-BCNFs and NIP-BCNFs from aqueous HSA solutions were investigated in a batch system. The selectivity of the MIP-cBCNFs was investigated by using non-template human transferrin (HTR), and myoglobin (Myo). The relative selectivity coefficients of the MIP-cBCNFs were calculated as 4.73 and 3.02 for HSA/HTR and HSA/Myo molecules, respectively. In addition, the depletion of HSA from artificial human plasma was confirmed by SDS-PAGE and 2-D gel electrophoresis. As a result, it has been shown that metal ion coordination interactions contribute to specific binding of template when preparing MIP-cBCNFs for the depletion of HSA with a high adsorption capacity, significant selectivity and reusability. © 2018

Boronate affinity chromatography is a common purification method used for isolation and purification of cis-diol containing biomolecules. Poly (hydroxyethyl methacrylate-co-vinyl phenyl boronic acid) [P(HEMA-VPBA)] nanoparticles were prepared by miniemulsion polymerization to use in RNA purification methods. The P(HEMA-VPBA) nanoparticles were characterized by particle size distribution, surface area, Fourier transform infrared spectroscopy and atomic force microscopy. The effects of temperature, pH, RNA concentration and different salt types on RNA binding on the P(HEMA-VPBA) nanoparticles were examined. It was observed that RNA binding was increased with the increasing of pH and max RNA binding was obtained at pH 9.0. RNA binding capacity of the P(HEMA-VPBA) nanoparticles was increased from 167mg/g to 601mg/g with addition of BaCl2 to the binding medium. Maximum RNA binding capacity of the P(HEMA-VPBA) nanoparticles was 172mg/g at 1.0mg/mL initial RNA concentration. The P(HEMA-VPBA) nanoparticles were reusable for RNA binding. RNA was also extracted from Escherichia coli cells and purified successfully using the P(HEMA-VPBA) nanoparticles.

Ermis, Nihal/0000-0002-0085-3076 WOS: 000419414800031 For selective and sensitive determination of L-phenylalanine (L-Phe) a novel and reliable electrochemical sensor has been developed based on molecular imprinting technique. Thiophen-3-carbonyl tryptophan (TP3C-Trp) has been synthesized and used as a novel monomer. L-Phe was used as template molecule and imprinted in presence of thiophen and thiophen-3-carbonyl tryptophan (TP3C-Trp), used as functional monomers. As a comparison a non-modified polymer surface was also prepared under same circumstances without template molecule, L-Phe. The characterization studies of both non-imprinted (NIP) and L-phenylalanine imprinted (MIP) electrochemical sensor surfaces were made by using atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), ellipsometry and contact angle measurements. The electrochemical characterization analysis were made via square wave and cyclic voltammetry. The linearity range and the detection limit of the developed sensor were obtained as 1.0 x 10(-8)-1.0 x 10(-7) M and 1.0 x 10(-9) M, respectively.

In this article, ion imprinted poly(hydroxyethyl methacrylate) (PHEMA) based supermacroporous cryogels were synthesized in the presence of a functional monomer, namely N-methacryloyl-histidine methyl ester (MAH), to be complexed with Ni(II) ions. Two types of cryogels (MIP1 and MIP2) were synthesized according to functional monomer/template [MAH/Ni(II)] complexing molar ratios. These cryogels were then characterized by swelling tests, FT-IR and SEM measurements and used for selective binding of Ni(II) ions from aqueous solutions and a certified material. The maximum adsorption capacities of MIP1 and MIP2 cryogels were found as 1.89 and 5.54 mg/g, respectively. Ni(II) imprinted cryogels exhibited excellent selectivity toward competitive metal ions [Fe(III), Cu(II) and Zn(II)] indicating important potential for selective removal of Ni(II) ions from aqueous solutions. In addition, Ni(II) imprinted cryogels were used repeatedly without a decrement in the binding capacity. © 2016 Elsevier B.V.

The protein C imprinted monolithic cryogel was synthesized using 2-hydroxyethyl methacrylate by redox cryo-polymerization method. The prepared monolithic cryogel was characterized by Fourier transform infrared spectroscopy, swelling test, surface area measurements, and scanning electron microscopy. The nonimprinted cryogel was prepared as well for control. Adsorption of protein C from aqueous solutions was investigated in a continuous mode and several parameters affecting adsorption performance were optimized. The maximum protein C adsorption amount was 30.4 mg/g. The selectivity studies were performed by monolithic column studies and fast protein liquid chromatography, using hemoglobin and human serum albumin as competing proteins. The relative selectivity coefficients were 2.37 and 8.89 for hemoglobin and human serum albumin, respectively. Reusability was tested for ten consecutive adsorption-desorption cycles, and no significant change in adsorption capacity was recorded. A pseudo-second-order model was suitable to interpret kinetic data, and the Langmuir model suited the adsorption isotherms well.

In this study, copper (II) ion (Cu+2) imprinted poly(hydroxyethyl methacrylate-N-metacryloyl-(L)-cysteine methyl ester [PHEMAC-Cu+2] nanoparticles were synthesized by two-phase mini-emulsion polymerization method and applied to the SPR sensor chip surface for the selective determination of the Cu+2 ions in both aqueous solution, Cu+2-spiked artificial urine and physiological serum samples to investigate the effects of metabolite residues during the analysis. The non-imprinted [PHEMAC] nanoparticles were synthesized by applying the same procedure for the [PHEMAC-Cu+2] nanoparticle synthesis except the addition of Cu+2 ions as a control experiment to evaluate the selectivity of the [PHEMAC-Cu+2] nanoparticles. Roughness differences between [PHEMAC-Cu+2] and [PHEMAC] nanoparticles showed that the imprinting process of Cu+2 ions was performed successfully. [PHEMAC-Cu+2] and [PHEMAC] SPR biosensors prepared by attaching nanoparticles onto the surface of sensor chips, were characterized by atomic force microscope, ellipsometer, contact angle measurements. Langmuir adsorption model was found the most applicable model for this affinity system. Results showed that Cu+2 affinity regions on the surface of [PHEMAC-Cu+2] SPR biosensor were homogeneously distributed and have a monolayer structure. Having the high imprinting efficiency with the imprinting factor of 4.74, the [PHEMAC-Cu+2] SPR biosensor was found to show more selectivity towards the target Cu+2 than the non-imprinted [PHEMAC] SPR biosensor. The selectivity studies of [PHEMAC-Cu+2] SPR biosensors for Cu+2 detection were investigated by using Zn+2 and Ni+2 solutions selected as competitor molecules. The results of intraday and interday precision studies were carried out to ascertain the reproducibility of the proposed method and reported as percent relative standard deviation (%RSD) value.

Synthesis of melamine (ME) imprinted polymeric sorbent for use as solid phase extraction adsorbent was targeted and the benefits of the synthesis in the monolith format were combined with imprinting technology advantages. Melamine as template and 2-vinylimidazole-Cu 2 + as complexing agent were used as the first time for pre-complex formation, followed by the preparation of monolith by bulk polymerization method in the presence of ethyleneglycol dimethacrylate as crosslinker, azobisisobutyronitrile as initiator, and ethyl alcohol as solvent for a duration of 4 h at 80 °C. 1.0 M NaOH solution was used as a desorption agent to remove template. Non-imprinted monolith (NIP) were synthesized as a control without template in same receipt. The monolith samples were characterized by Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), elementary analysis, and Branauer- Emmett- Teller (BET) studies. Melamine adsorption from aqueous solution was studied in continuous mode, and some parameters such as pH, temperature, concentration and flow-rate were optimized for melamine adsorption. The maximum adsorption capacities were determined as 147.9 mg/g for imprinted polymer (MIP), 82.0 mg/g for non-imprinted polymer (NIP) and 4.0 mg/g for polymer without pre-complex (E) at 25 °C, and pH 5.0 with 500 ppm melamine initial concentration for 1.0 mL/min flow-rate. In addition to interaction characterized by metal coordination bond formation, non- covalent interactions were responsible for melamine adsorption. No significant change in adsorption performance was recorded after 10 consecutive adsorption-desorption cycles. Kinetic analysis indicated compliance with pseudo-second order kinetics. The Freundlich isotherm was found suitable for description of the process. Cyanuric acid (CY), aniline (AN), and phenol (PH) were used as competing agents in selectivity studies, and relative selectivity coefficients were calculated (k' CY = 4.45; k' AN = 7.08; k' PH = 3.98). The performance of melamine imprinted polymeric monolith (MIP) as solid-phase extraction adsorbent for extraction of melamine from milk samples was investigated and the recovery of melamine in spiked milk samples was 97.6% with the relative standard deviation (RSD) (8.1%).

Immobilized metal ion affinity chromatography is one of the methods used for the adsorption of proteins. In this study, poly(glycidyl methacrylate) cryogel discs were prepared by free radical polymerization. The metal chelating groups were polymeric chain of poly-( l )-histidine (mol wt ≥ 5000) having poly-imidazole ring sequence. Then, Cu(II), Zn(II), and Ni(II) ions were separately chelated on the poly-( l )-histidine immobilized poly(glycidyl methacrylate) cryogel discs to be used in immobilized metal ion affinity chromatography separation of lysozyme. The swelling test, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller, and scanning electron microscopy were performed to characterize both poly(glycidyl methacrylate) and poly-( l )-histidine immobilized poly(glycidyl methacrylate) cryogel discs. The effects of the pH, lysozyme concentration, adsorption time, and ionic strength on the adsorption capacity were studied. These parameters were varied between 4.0 and 8.0 for pH, 0.0 and 2.0 mg/ml for initial lysozyme concentration, 0 and 120 min for adsorption time, and 0.0 and 1.0 µM for ionic strength. The maximum lysozyme adsorption capacity of the Cu(II), Zn(II), and Ni(II) ions chelated poly-( l )-histidine immobilized poly(glycidyl methacrylate) cryogel discs was 36.4, 26.8, and 17.3 mg/g cryogel, respectively. Desorption of lysozyme from cryogel discs was easily achieved by 1.0 M NaCI solution. Repeated adsorption-elution processes showed that these cryogel discs were suitable for repeatable lysozyme adsorption. Adsorption isotherms fitted to Langmuir model and adsorption kinetics suited to pseudo-second order model. Thermodynamic parameters (i.e. ΔH°, ΔS°, ΔG°) were also calculated from Langmuir isotherms at different temperatures.

In this work, poly(HEMA-MAPA) membranes were prepared by UV-polymerization technique. These membranes were characterized by SEM, FTIR, and swelling studies. Synthesized membranes had high porous structure. These membranes were used for controlled release of curcumin which is already used as folk remedy and used as drug for some certain diseases and cancers. Curcumin release was investigated for various pHs and temperatures. Optimum drug release yield was found to be as 70% at pH 7.4 and 37 °C within 2 h period. Time-depended release of curcumin was also investigated and its slow release from the membrane demonstrated within 48 h.

Monodisperse magnetic acrylate based particles (5.0 µm in diameter) containing histidine were synthesized using a modified suspension polymerization method for the purification of immunoglobulin G from human plasma in a magnetically stabilized fluidized bed. N-methacryloyl-(L)-histidine methyl ester (MAH) was used as pseudo-specific ligand/co-monomer. MAH content of the magnetic particles was calculated as 55.3 µmol MAH/g polymer using elemental analysis. Immunoglobulin G binding amount of the magnetic particles decreased with increase of the flow-rate. The maximum immunoglobulin G binding was observed at pH 7.4 (phosphate buffer). Immunoglobulin G binding amount onto the magnetic poly(ethylene glycol dimethacrylate) [mPEGDMA] particles was found to be almost negligible due to the hydrophilic polymer structure. High binding values were obtained from aqueous solutions (1646 mg/g). Higher immunoglobulin G binding was observed when human plasma was used (2169 mg/g). Purity of the separated immunoglob...

In this study, composite polymeric cryogel cartridges were achieved by using Cd(II) imprinted poly(hydroxyethyl methacrylate N-methacryloly-(L)-cysteine methylester) beads and poly(hydroxyethyl methacrylate) cryogel cartridges with two different mole ratios of functional monomer. The N-methacryloly-(L)-cysteinemethylester was used as a functional monomer and Cd(II) 1:1 and 2:1, which were then notated as MIP1 and MIP2, respectively. Various characterization methods have confirmed the structural transformation on the MIP1 and MIP2 composite cryogel cartridges by scanning electron microscopy, Fourier-transform infrared spectroscopy-Attenuated Total Reflectance, and swelling tests. The maximum amount of Cd(II) adsorption with composite cryogel cartridges was determined by altering the Cd(II) initial concentration, temperature, and pH values. The maximum adsorption capacity of MIP1 and MIP2 composite cryogel cartridges obtained was 76.35 and 98.8 &micro, mol/g of composite cryogels, respectively. The adsorption studies revealed that the MIP2 possessed a good adsorption performance for Cd(II). The obtained composite cryogel cartridges have a selective, reusable, and cost-friendly potential for the removal of Cd(II) from aqueous solutions, and are used many times without decreasing their adsorption capacities significantly. The Cd(II) removal rate of the MIP1 and MIP2 composite cryogel cartridges from synthetic wastewater samples was determined as 98.8%. The obtained cryogel cartridges&rsquo, adsorption material exhibited a good directional removal performance for Cd(II) from wastewater samples.

The novel nanosensor based on Surface Plasmon Resonance (SPR) was developed for sensitive and selective detection of ciprofloxacin via molecularly imprinted nanoparticles (MIP/NPs). NPs were synthesized through miniemulsion polymerization technique with methacrylic acid as a functional monomer. FTIR, SEM, zetasizer and contact angle measurements were used for the characterization of MIP/NPs. After modification the SPR chip surface, the nanosensor was used for detection of ciprofloxacin in aqueous solution. According to selected concentration range, the correlation coefficient and limit of detections were obtained as 0.993 (R2) and 3.21 and 7.1 ppb in ultrapure water and SWW, respectively. Association kinetic analysis, Scatchard, Freundlich, Langmuir and Freundlich-Langmuir isotherms were also performed on the data to investigate adsorption behaviour of ciprofloxacin on the surface of nanosensor. Tetracycline and enrofloxacin were used as competitor agents to examine the selectivity of nanosensor. ...

Pharmaceutically active compounds like diclofenac (DFS), ibuprofen (IBP), and other drugs that persist in the environment are listed as emerging contaminants. These escape from normal wastewater treatment plants and find their way to water streams; therefore, alternate treatment processes are needed. Herein, a sorbent material is reported that is prepared through hydrotermal carbonization from dried fruit powder of Zizipus mauritiana L. (HTC-ZM) and applied for simultaneous removal of DFS and IBP. Carbonized material (HTC-ZM) was found as agglomerates of approximately 1 μm particle size with surface area of 1160 m2/g having oxygen functional groups (e.g., COO, O, C=O) on surface. Simultaneous removal of IBP and DFS onto HTC-ZM was studied using response surface methodology with a set of 18 experiments using factors such as pH, amount of sorbent, contact time, and sorbate concentration. Maximum removal efficiency was obtained 88% and 97% for DFS and for IBP, respectively, with adsorption capacity of 2.03 mmol g−1 for DFS and 2.54 mmol g−1 for IBP. Kinetics modeling and “mean free energy” values predicted that sorption is mainly governed by physical interactions followed by “pore filling” mechanism for uptake of DFS and IBP.

Molecular imprinting technique was used for the preparation of antibiotic and anti-neoplastic chemotherapy drug (mitomycin C) imprinted cryogel membranes (MMC-ICM). The membranes were synthezied by using metal ion coordination interactions with N-methacryloyl-(l)-histidine methyl ester (MAH) functional monomer and template molecules (i.e. MMC). The 2-hydroxyethyl methacrylate (HEMA) monomer and methylene bisacrylamide (MBAAm) crosslinker were used for the preparation of mitomycin C imprinted cryogel membranes by radical suspension polymerization technique. The imprinted cryogel membranes were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) and swelling degree measurements. Cytotoxicity of MMC-ICMs was investigated using mouse fibroblast cell line L929. Time-dependent release of MMC was demonstrated within 150 h from cryogel membranes. Cryogels demonstrated very high MMC loading efficiency (70-80%) and sustained MMC release over hours.

Poly(2-hydroxyethyl methacrylate-glycidyl methacrylate) [p(HEMA-GMA)] cryogel discs were prepared under sub-zero temperatures. Gelatin was attached covalently on the p(HEMA-GMA) cryogel discs and reversible immobilization of horseradish peroxidase (HRP) was performed. The p(HEMA-GMA) cryogel discs were characterized by swelling tests, scanning electron microscopy, and surface area measurements. HRP immobilization capacity of p(HEMA-GMA)/gelatin cryogel discs was 24.8 mg/g. Removal of phenol from aqueous solutions was performed using HRP immobilized p(HEMA-GMA)/gelatin cryogel. It was observed that within 2 h of contact time, the percentage of phenol removal reaches up to 91% in the presence of H2O2.

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 investigate the usability of cryogel columns for the purification of invertase from Saccharomyces cerevisiae. Poly(2-hydroxyethyl methacrylate) monolithic columns were produced via cryogelation. Ester groups of the poly(2-hydroxyethyl methacrylate) structure were then converted to imine groups by the reaction with poly(ethylene imine) in the presence of NaHCO3. Transition metal ions, Cu(II), Co(II), and Ni(II), were chelated on the PEI-modified cryogel columns. Purification of invertase from natural source namely S. cerevisiae was also studied, and the purification fold values were obtained as 41.350, 44.714, and 30.302 for Cu(II)-chelated, Co(II)-chelated, and Ni(II)-chelated PHEMA/PEI columns, respectively.

A hydrophobic group/comonomer N-methacryloyl-(l)-alanine (MAAL) containing 2-hydroxyethyl methacrylate (HEMA)-based magnetic hydrophobic nanoparticles was synthesized by using a microemulsion polymerization technique for immobilization of amyloglucosidase (AMG). The magnetic hydrophobic nanoparticles with an average diameter of 79 nm were characterized with Fourier transform infrared spectroscopy, transmission electron microscopy, zeta-size analysis, and electron spin resonance spectroscopy. Hereby, the effecting factors such as initial concentration of AMG, pH, and temperature on the immobilization were investigated. After determining the optimum immobilization conditions, the kinetic constants (KM and Vmax) and properties of free and immobilized AMG were investigated in batch studies. The maximum AMG adsorption capacity of the magnetic hydrophobic nanoparticles was 294.42 mg/g at pH 3.0. The optimum pH and temperature for free and immobilized AMG were found to be pH 5.0 and 60 °C. The KM value for immob...

A new type of polymethacrylate-based monolithic column with chiral stationary phase was prepared for the enantioseparation of aromatic amino acids, namely D,L-phenylalanine, D,L-tyrosine, and D,L-tryptophan by CEC. The monolithic column was prepared by in situ polymerization of butyl methacrylate (BMA), N-methacryloyl-L-histidine methyl ester (MAH), and ethylene dimethacrylate (EDMA) in the presence of porogens. The porogen mixture included DMF and phosphate buffer. MAH was used as a chiral selector. FTIR spectrum of the polymethacrylate-based monolith showed that MAH was incorporated into the polymeric structure via in situ polymerization. Some experimental parameters including pH, concentration of the mobile phase, and MAH concentration with regard to the chiral CEC separation were investigated. Single enantiomers and enantiomer mixtures of the amino acids were separately injected into the monolithic column. It was observed that L-enantiomers of aromatic amino acids migrated before D-enantiomers. The reversal enantiomer migration order for tryptophan was observed upon changing of pH. Using the chiral monolithic column (100 μm id and 375 μm od), the best chiral separation was performed in 35:65% ACN/phosphate buffer (pH 8.0, 10 mM) with an applied voltage of 12 kV in CEC. SEM images showed that the chiral monolithic column has a continuous polymeric skeleton and large through-pore structure.

Poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) [poly(HEMA-GMA)] cryogel was synthesized by cryopolymerization technique at frozen temperature. Iminodiacetic acid (IDA) was then attached covalently to the cryogel as a chelating agent. Then, poly(HEMA-GMA)-IDA cryogel was chelated with Ni(II) ions and this novel metal affinity support was used for adsorption of urease from its aqueous solution. Urease adsorption experiments were carried out in a continuous system by using a peristaltic pump. Maximum urease adsorption onto poly(HEMA-GMA)-IDA-Ni(II) cryogel was found to be 11.30 mg/g cryogel at pH 5.0 acetate buffer and in 25 °C medium temperature. Urease adsorption capacity decreased with increasing ionic strength and increasing chromatographic flow rate. Adsorption kinetics of urease onto poly(HEMA-GMA)-IDA-Ni(II) cryogel was also investigated and it was found that Langmuir adsorption model is applicable for this adsorption study. This novel immobilized metal affinity chromatography support was used 10 times without any decrease at their adsorption capacity. It was also observed that urease enzyme was repeatedly adsorbed and desorbed without significant lost in enzymatic activity.

WOS: 000320895900004, In this study, we applied the epitope imprinting approach to prepare molecularly imprinted monolithic cryogels for immunoglobulin G (IgG) recognition. In this respect, we imprinted F-ab fragments of IgG molecules instead of intact protein molecules via two different non-covalent interactions. In the first approach, we directly coordinated F-ab fragments with N-methacryloyl-L-histidine (MAH), polymerizable derivative of L-histidine, but for the second, we used cupric ions [Cu(II)] as mediator between MAH and F-ab fragments. The monolithic cryogels were characterized by Fourier transform infrared (FTIR) spectroscopy, swelling test, and scanning electron microscopy. Then, the monolithic cryogels were used for F-ab fragment adsorption from aqueous solution while evaluating the factors such as pH and F-ab fragment concentration affecting on adsorption process in continuous set-up. After that, monolithic cryogels were used for IgG adsorption by varying pH, IgG concentration, flowrate, and temperature in appropriate ranges. Maximum IgG adsorption capacities were determined as 32.4 mg/g and 49.0 mg/g for directly coordinated cryogel (MIPDirect) and Cu(II) assisted cryogel (MIPCu(II) (assisted)), respectively. Non-imprinted monolithic cryogels were also prepared for control purposes. In addition to F-ab fragments and IgG molecules, albumin and F-c fragment of IgG molecules were used as competitor biomolecules in order to investigate the selectivity gained by imprinting process. Relative selectivity constants were calculated as 1.47, 2.64 and 3.89 for MIPDirect and 2.90, 8.98, and 11.51 for MIPCu(II) (assisted) for F-ab/IgG, F-ab/F-c, and F-ab/albumin as biomolecule pairs, respectively. The desorption efficiency and reusability of MIPCu(II) assisted cryogel were better than that of MIPDirect. The results reported here showed that the metal ion assistance improved the selectivity features of the imprinted cryogels and allowed to study under milder conditions with enhanced adsorptive properties

There is a significant need for the development of the novel adsorbents in the field of protein purification. In this study, thin hemoglobin imprinted film (MIP) was fabricated onto the bacterial cellulose nanofibers' (BCNFs) by surface imprinting method using metal ion coordination interactions with N-methacryloyl-(L)-histidinemethylester (MAH) and copper ions. The hemoglobin surface imprinted bacterial cellulose nanofibers (MIP-BCNFs) was applied to selective recognition of hemoglobin and purification from hemolysate. The characterization of the MIP-BCNFs was carried out by the Fourier Transformed Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), micro-Computerized Tomography (mu CT), atomic force microscopy (AFM) and surface area measurements. The adsorption experiments of hemoglobin onto the MIP-BCNFs and NIP-BCNFs from aqueous hemoglobin solutions were investigated in a batch system. The results showed that MIP-BCNFs are promising materials for purification of hemoglobin with high adsorption capacity, significant selectivity and reusability. (C) 2017 Elsevier B.V. All rights reserved.

WOS: 000394064800071, PubMed: 28183651, This study reports a surface plasmon resonance (SPR) based affinity sensor system with the use of molecular imprinted nanoparticles (plastic antibodies) to enhance the pesticide detection. Molecular imprinting based affinity sensor is prepared by the attachment of atrazine (chosen as model pesticide) imprinted nanoparticles onto the gold surface of SPR chip. Recognition element of the affinity sensor is polymerizable form of aspartic acid. The imprinted nanoparticles were characterized via FTIR and zeta-sizer measurements. SPR sensors are characterized with atomic force microscopy (AFM), scanning electron microscopy (SEM), Fourier transform infrared spectrophotometry (FTIR) and contact angle measurements. The imprinted nanoparticles showed more sensitivity to atrazine than the non-imprinted ones. Different concentrations of atrazine solutions are applied to SPR system to determine the adsorption kinetics. Langmuir adsorption model is found as the most suitable model for this affinity nanosensor system. In order to show the selectivity of the atrazine-imprinted nanoparticles, competitive adsorption of atrazine, simazine and amitrole is investigated. The results showed that the imprinted nanosensor has high selectivity and sensitivity for atrazine. (C) 2016 Elsevier B.V. All rights reserved., Ministry of Food, Agriculture and Livestock, of Republic of Turkey [TAGEM 12/AR-GE/35], This research has been carried out with supports from the Ministry of Food, Agriculture and Livestock, of Republic of Turkey with grant number TAGEM 12/AR-GE/35.

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.

WOS: 000386402900054, PubMed: 27411294, Molecular imprinted polymers (MIPs) are tailor-made materials with selective recognition to the target. The goals of this study were to prepare cholesterol imprinted polymeric nanospheres (CIPNs) and optimize their adsorption parameters and also to use CIPNs for adsorption of cholesterol (CHO), which is an important physiological biomacromolecule, from gastrointestinal mimicking solution (GIMS). Pre-polymerization complex was prepared using CHO as template and N-methacryloylamido-(L)-phenylalanine methyl ester (MAPA). This complex was polymerized with 2-hydroxyethyl methacrylate (HEMA). CHO was removed by MeOH and tetrahydrofuran (THF). Adsorption studies were performed after chacterization studies to interrogate the effects of time, initial concentration, temperature, and ionic strength on CHO adsorption onto CIPNs. Maximum adsorption capacity (714.17 mg/g) was higher than that of cholesterol imprinted polymers in literature. Pseudo-second-order kinetics and Langmuir isotherm fitted best with the adsorption onto CIPNs. 86% of adsorbed cholesterol was desorbed with MeOH:HAc (80:20, v/v) and CIPNs were used in adsorption-desorption cycle for 5-times with a decrease as 12.28%. CHO analogues; estron, estradiol, testosterone, and progesterone were used for competitive adsorption. The relative selectivity coefficients of CINPs for cholesterol/estron and cholesterol/testosterone were 3.84 and 10.47 times greater than the one of non-imprinted polymeric nanospheres (NIPNs) in methanol, respectively., Dokuz Eylul University, Turkey [2012-KBFEN-107], This study was financially supported by the Scientific Research Projects Coordination of Dokuz Eylul University, Turkey (Project number: 2012-KBFEN-107).

Supermacroporous cryogel with an average pore size of 10–200 μm in diameter was prepared by cryopolymerization of N-methacryloyl-( l )-glutamic acid (MAGA) and 2-hydroxyethyl methacrylate (HEMA). The poly(HEMA–MAGA) cryogel was characterized by surface area measurements, FTIR, swelling studies, elemental analysis and SEM. The poly(HEMA–MAGA) cryogel had a specific surface area of 23.2 m 2 /g. The equilibrium swelling ratio of the cryogel is 9.68 g H 2 O/g for poly(HEMA–MAGA) and 8.56 g H 2 O/g cryogel for PHEMA. The poly(HEMA–MAGA) cryogel disks with a pore volume of 71.6% containing 878 μmol MAGA/g were used in the removal of UO 2 2+ from aqueous solutions. Adsorption equilibrium of UO 2 2+ was obtained in about 30 min. The adsorption of UO 2 2+ ions onto the PHEMA cryogel disks was negligible (0.78 mg/g). The MAGA incorporation significantly increased the UO 2 2+ adsorption capacity (92.5 mg/g). The adsorption process is found to be a function of pH of the UO 2 2+ solution, with the optimum value being pH 6.0. Adsorption capacity of MAGA contained PHEMA based cryogel disks increased significantly with pH and then reached the maximum at pH 6.0. Consecutive adsorption and elution cycles showed the feasibility of repeated use for poly(HEMA–MAGA) cryogel disks.

A novel N-methacryloyl-L-tryptophan methyl ester (MATrp) containing poly (hydroxyethyl methacrylate) cryogel (PHEMATrp) disc was prepared for removal of bilirubin (BR) out of human plasma. PHEMATrp cryogel disc was produced by bulk polymerization, with high gelation yield up to 92% and characterized by swelling tests, scanning electron microscopy (SEM), elemental analysis, Brunauer– Emmett–Teller (BET) analysis, contact angle measurements and surface energy calculations. BR adsorption studies were performed in a batch system, and the maximum BR adsorption capacity was found as 22.2 mg/g cryogel disc.

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.

WOS: 000304429700003, Magnetic poly(2-hydroxyethylmethacrylate) [mPHEMA] beads were prepared by suspension polymerization of HEMA in the presence of Fe3O4 nano-powder. Cibacron Blue F3GA (CB) was covalently immobilized to the mPHEMA beads via nucleophilic substitution reaction between chloride of its triazine ring and hydroxyl groups of HEMA under alkaline conditions. The mPHEMA/CB beads (100-140 mu m in diameter) carrying 68.3 mu mol CB/g polymer were used in a-amylase adsorption studies to assess the effects of pH, initial protein concentration, temperature and ionic strength on enzyme activity. Maximum adsorption capacity of mPHEMA/CB beads was found to be 401 +/- 11 mg/g carrier. The adsorbed amounts of a-amylase per unit mass of magnetic beads reached a plateau value at about 1.0 mg/mL at pH 5.0. The optimal pH for free and immobilized a-amylase was 7.0 and 8.0, respectively. The immobilized enzyme exhibited better thermostability than the free one. The free enzyme lost all of its activity within 35 days whereas the immobilized enzyme lost about 27% of its activity during the same period. It was also observed that the enzyme could be repeatedly adsorbed and desorbed onto the mPHEMA/CB beads. (C) 2012 Elsevier B.V. All rights reserved.

WOS: 000303299300046, Hydrophobic interaction chromatography (HIC) is increasingly used for protein purification, separation and other biochemical applications. The aim of this study was to prepare hydrophobic microbeads and to investigate their recombinant human interferon-alpha (rHuIFN-alpha) adsorption capability. For this purpose, we had synthesized functional monomer, N-methacryloyl-L-phenylalanine (MAPA), to provide a hydrophobic functionality to the adsorbent. The poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-phenylalanine) [poly(HEMA-MAPA)] microbeads were prepared by suspension copolymerization. microbeads were characterized using FTIR, swelling behavior, and SEM micrographs. Equilibrium swelling ratio of poly(HEMA-MAPA) and poly(HEMA) microbeads were 53.3% and 69.3%, respectively. The specific surface area and average pore diameters determined by BET apparatus were 17.4 m(2)/g and 47.3 angstrom for poly(HEMA) microbeads and 18.7 m(2)/g and 49.8 angstrom for poly(HEMA-MAPA) microbeads. Adsorption experiments were performed under different conditions. Maximum rHuIFN-alpha adsorption capacity was found to be 137.6 +/- 6.7 mg/g by using poly(HEMA-MAPA) microbeads with a size range of 150-250 mu m and containing 327 mu mol MAPA/g microbeads. Compared with poly(HEMA-MAPA) microbeads, nonspecific rHuIFN-alpha adsorption onto plain poly(HEMA) microbeads was very low, about 4.2 +/- 2.3 mg/g. To determine the effects of adsorption conditions on possible conformational changes of rHuIFN-alpha structure, fluorescence spectrophotometry was employed. Repeated adsorption-elution processes showed that these microbeads are suitable for repeatable rHuIFN-alpha adsorption

Glycoamylase (AMG) is an ?-amylase enzyme which catalyzes the breakdown of large a(1,4)-linked malto-oligosaccharides to glucose. It is an extracellular enzyme and is excreted to the culture medium. In this study, AMG was immobilized on a variety of metal affinity membranes, which were prepared by chelating Cu2+ ions onto poly(hydroxyethyl methacrylate) (PHEMA) using N-methacryloyl-(L)-histidine methyl ester (MAH), N-methacryloyl-(L)-cysteine methyl ester (MAC), and N-methacryloyl-(L)-phenylalanine methyl ester (MAPA) as metal-chelating comonomers for reversible immobilization of AMG. The PHEMAH, PHEMAC, PHEMAPA membranes were synthesized by UV-initiated photo-polymerization and Cu2+ ions were chelated on the membrane surfaces. Cu2+-chelated membranes were characterized by swelling tests, SEM, contact angle measurements, elemental analysis, and FTIR. AMG immobilization on the Cu2+-chelated membranes was performed by using aqueous solutions of different amounts of AMG at different pH values and Cu2+ loadings. Durability tests concerning desorption of AMG and reusability of the Cu2+-chelated membranes yielded acceptable results. It was computationally determined that AMG possesses four likely Cu2+/Zn2+ binding sites, away from the catalytic site, to which the metal-chelated membranes can be efficiently used. (C) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

WOS: 000302607100019, PubMed ID: 22275267, A molecular recognition based L-glutamic acid (L-GLU) imprinted cryogel was prepared for L-GLU separation via chromatographic applications. The novel functional monomer N-methacryloyl-(L)-glutamic acid-Fe3+ (MAGA-Fe3+) was synthesized to be complex with L-GLU. The L-GLU imprinted cryogel was prepared by free radical polymerization under semifrozen conditions in the presence of a monomer-template complex MAGA-Fe3+-L-GLU. The binding mechanism of MAGA-Fe3+ and L-GLU was characterized by Fourier transform infrared (FTIR) spectroscopy in detail. FTIR analyses on the synthesized MAGA-Fe3+-GLU complex reveals bridging bidentate and monodentate binding modes of Fe3+ in complex with the carboxylate groups of the glutamate residues. The template L-GLU could be reversibly detached from the cryogel to form the template cavities using a 100 mM solution of HNO3. The amount of adsorbed L-GLU was detected using the phenyl isothiocyanate method. The L-GLU adsorption capacity of the cryogel decreased drastically from 11.3 to 6.4 mu mol g-1 as the flow rate increased from 0.5 to 4.0 mL min-1. The adsorption onto the L-GLU imprinted cryogel was highly pH dependent due to electrostatic interaction between the L-GLU and MAGA-Fe3+. The PHEMAGA-Fe3+-GLU cryogel exhibited high selectivity to the corresponding guest amino acids (i.e., D-GLU, L-ASN, L-GLN, L-, and D-ASP). Finally, the L-GLU imprinted cryogel was recovered and reused many times, with no significant decrease in their adsorption capacities

WOS: 000300133000004, A poly (acrylamide-allylglycidyl ether) [p(AAm-AGE)] cryogel was prepared by radical polymerization of acrylamide (AAm) and allylglycidyl ether (AGE). Cibacron Blue F3GA (CB) was covalently attached to the p(AAm-AGE) cryogel via the reaction between the chloride groups of the reactive dyes and the epoxide groups of the AGE. The CB-attached p(AAm-AGE) cryogel was chelated with Fe3+ ions. This immobilized metal ion affinity chromatography (IMAC) cryogel carrying 25.8 +/- 2.0 mu mol Fe3+ ions was used in adsorption studies to interrogate the effects of pH, protein initial concentration, flow rate, temperature and ionic strength on enzyme activity. Maximum adsorption capacities were found to be 75.7 +/- 1.2 mg/g for p(AAm-AGE)-CB-Fe3+ cryogels and 60.6 +/- 1.0 mg/g for p(AAm-AGE)-CB cryogels, respectively. The adsorbed amounts of catalase per unit mass of cryogel reached a plateau value at about 1.5 mg/mL at pH 6.0. The K-m values were found to be 0.73 +/- 0.02 g/L for the free catalase and 0.18 +/- 0.02 g/L for the immobilized catalase. The V-max value of free catalase (2.0 x 10(3) U/mg enzyme) was found to be lower than that of the immobilized catalase (2.5 x 10(3) U/mg enzyme). It was also observed that the enzyme could be repeatedly adsorbed and desorbed onto the p(AAm-AGE)-CB-Fe3+ cryogel. (C) 2011 Elsevier Ltd. All rights reserved.

WOS: 000088276300002 Microporous poly(2-hydroxyethylmethacrylate) [pHEMA] membranes carrying Cibacron Blue F3GA and/or thionein were prepared and used for cadmium(II) removal from human plasma. pHEMA membranes were produced by a photopolymerization of HEMA in the presence of azobisisobutyronitrile. The reactive dye-ligand Cibacron Blue F3GA was then covalently attached onto the pHEMA membranes. The maximum dye-loading was 1.07 mu mol/cm(2). Then, thionein was adsorbed onto the Cibacron Blue F3GA-carrying membranes. The maximum amount of thionein adsorbed was 0.92 mu mol/cm(2). The aqueous swelling properties and contact angle lair underwater) of the pHEMA membrane were not observed to change following derivatisation with Cibacron Blue F3GA. These hydrophilic membranes (contact angle value: 45.3 degrees) with a swelling ratio of 58% (w/w), and carrying Cibacron Blue F3GA and/or thionein were used in the Cd(II) removal studies. The maximum amounts of Cd(II) removed from human plasma by Cibacron Blue F3GA-attached and Cibacron Blue F3GA-attached/thionein adsorbed pHEMA membranes were of 1.72 mu mol used as pectively. Cd(II) ions could be repeatedly adsorbed and desorbed with both types of these novel metallo-peptide affinity pHEMA membranes without noticeable loss in their Cd(II) adsorption capacity. (C) 2000 Elsevier Science B.V. All rights reserved.