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Abstract Immunoaffinity chromatography has a huge interest in the biomedical and biotechnological fields, in particular for one-step isolation, purification and removal of analyte compounds. In this study, uniform-sized microcryogels, a new type of cryogels, were synthesized using 2-hydroxyetyhl methacrylate and epoxy-group-containing monomer, glycidyl methacrylate for purification of a plasma protein, transferrin. Immunoaffinity microcryogels containing anti-Tf antibodies were characterized by Raman spectroscopy, Fourier transform infrared spectroscopy, optical microscopy, scanning electron microscopy, density measurements and swelling tests. Adsorption studies in aqueous media were carried out in order to examine the effects of medium pH, initial concentration of analyte and contact time. It was found that the optimum pH was 6.0 and the maximum adsorption capacity of immunoaffinity microcryogels at this pH value found to be 9.82 mg/g. The K L constant for Langmuir isotherm was calculated as 2.65 mL/mg. The maximum adsorption capacity obtained from experimental studies is also very close to the calculated Langmuir adsorption capacity (11.27 mg/g). Langmuir adsorption isotherms and pseudo-second-order kinetic models are consistent with the adsorption process, which means that the adsorption is single layered and chemically controlled. The purity of the eluted hsTf from plasma was about 84% with yield about 82%. After the tenth use of the same microcryogels, the maximum hsTf adsorption capacity decreased by about 20%. The results indicated that the immunoaffinity microcryogels having anti-Tf antibody ligands could be a safe and cost-friendly method for purification of transferrin. Highlights • A new type of cryogel as an adsorbent is presented by synthesizing uniform-sized microcryogels. • Immunoaffinity microcryogels are produced for purification of human serum transferrin. • Simple production process; reusable and cost-friendly adsorbents. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • New generation of cryogels, i.e. microcryogels, as plastic antibodies for transferrin. • Highly selective products fabricated using molecular imprinting technology. • A low-cost alternative to commercial disposable immunoaffinity adsorbents. • High stability and high regeneration capacity after ten successive runs. Abstract Molecular imprinting technology (MIT) presents self-organization of functional monomers around a template, leading formation of specific recognition sites for the template with high selectivity. In this study, cryogels in microscale were fabricated as novel plastic antibodies via MIT for transferrin purification. After chemical and physical characterization studies, optimal hsTf adsorption conditions for the plastic antibodies were then determined by investigating parameters including medium pH and temperature, initial analyte concentration and salt concentration. Selectivity studies were performed by considering both size and isoelectric points of the proteins. Compared with the non-imprinted P(HEMATrp) microcryogels, the relative selectivity coefficients of the plastic antibodies for hsTf/MYB and hsTf/HSA were found to be 2.24 and 2.10 times higher, respectively. The findings indicated that the molecularly imprinted microcryogels could be selective, reusable and cost-friendly potential plastic antibodies for purification of transferrin. [ABSTRACT FROM AUTHOR]

Hemoglobin is an iron carrying protein in erythrocytes and also an essential element to transfer oxygen from the lungs to the tissues. Abnormalities in hemoglobin concentration are closely correlated with health status and many diseases, including thalassemia, anemia, leukemia, heart disease, and excessive loss of blood. Particularly in resource-constrained settings existing blood analyzers are not readily applicable due to the need for high-level instrumentation and skilled personnel, thereby inexpensive, easy-to-use, and reliable detection methods are needed. Herein, a molecular fingerprints of hemoglobin on a nanofilm chip was obtained for real-time, sensitive, and selective hemoglobin detection using a surface plasmon resonance system. Briefly, through the photopolymerization technique, a template (hemoglobin) was imprinted on a monomeric (acrylamide) nanofilm on-chip using a cross-linker (methylenebisacrylamide) and an initiator-activator pair (ammonium persulfate-tetramethylethylenediamine). The molecularly imprinted nanofilm on-chip was characterized by atomic force microscopy and ellipsometry, followed by benchmarking detection performance of hemoglobin concentrations from 0.0005 mg mL-1 to 1.0 mg mL-1. Theoretical calculations and real-time detection implied that the molecularly imprinted nanofilm on-chip was able to detect as little as 0.00035 mg mL-1 of hemoglobin. In addition, the experimental results of hemoglobin detection on the chip well-fitted with the Langmuir adsorption isotherm model with high correlation coefficient (0.99) and association and dissociation coefficients (39.1 mL mg-1 and 0.03 mg mL-1) suggesting a monolayer binding characteristic. Assessments on selectivity, reusability and storage stability indicated that the presented chip is an alternative approach to current hemoglobin-targeted assays in low-resource regions, as well as antibody-based detection procedures in the field. In the future, this molecularly imprinted nanofilm on-chip can easily be integrated with portable plasmonic detectors, improving its access to these regions, as well as it can be tailored to detect other proteins and biomarkers. [ABSTRACT FROM AUTHOR]

The detection and identification of clinical biomarkers with related sensitivity have become a source of considerable concern for biomedical analysis. There have been increasing efforts toward the development of single-molecule analytical platforms to overcome this concern. The latest developments in plasmonic nanomaterials include fascinating advances in energy, catalyst chemistry, optics, biotechnology, and medicine. Nanomaterials can be successfully applied to biomolecule and drug detection in plasmonic nanosensors for pharmaceutical and biomedical analysis. Plasmonic-based sensing technology exhibits high sensitivity and selectivity depending on surface plasmon resonance (SPR) or localized surface plasmon resonance (LSPR) phenomena. In this critical paper, we offer an overview of the methodology of the SPR, LSPR, surface-enhanced Raman scattering (SERS), surface-enhanced infrared absorption (SEIRA), surface-enhanced fluorescence (SEF), and plasmonic nanoplatforms advanced for pharmaceutical and biomedical applications. First of all, we present here a brief discussion of the above trends. We have devoted the last section to the explanation of SPR, LSPR, SERS, SEIRA, and SEF platforms, which have found a wide range of applications, and reviewed recent advances for biomedical and pharmaceutical analysis. ● Nanomaterials and nanostructured surfaces are widely used in biomedical applications. ● Plasmonic-based nanosensors allow the sensitive sensing of biomolecules at low detection limits. ● Plasmonic nanosensors contribute to the focus on diagnosis with ultrasensitive detection methods. ● Surface plasmon resonance sensing is suited for early detection profiling. [ABSTRACT FROM AUTHOR]

The aim of this study is the synthesis of nanoparticles with selective arsenic recognition capability for the removal of arsenic from water. Arsenic recognition based molecularly imprinted (As(V)-MIP) were synthesized using the molecular imprinting technique via mini-emulsion polymerization. The synthesized As(V)-MIP nanoparticles were characterized using zeta sizer, zeta potential, FTIR, Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and elemental analysis. The adsorption behavior of nanoparticles was investigated in a batch system at pH 4.0–9.0. The maximum adsorption capacity of As(V)-MIP nanoparticles was determined to be 54.29 mg As/g polymer at pH 5.0. Various parameters such as pH, concentration and adsorption time were examined to determine the optimum adsorption conditions. As(V)-MIP nanoparticle selectivity experiments were conducted in the presence of NO3−, PO43−, and SO42− anions to determine the relative selectivity coefficients (K'). The experimental data showed a good correlation with the Langmuir isotherm equation and adherence of the adsorption process to pseudo-second-order kinetics was observed. Applying As(V)-MIP nanoparticles to real water sample showed up to 95.3% As(V) removal efficiency. Reusability experiments were performed by renewal of nanoparticles using a 1 M HNO3 solution containing 0.05% thiourea. [ABSTRACT FROM AUTHOR]

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 immunoglobulin G from human plasma was found to be 87%. Magnetic PEGDMAH particles could be used many times without significant loss in protein binding amount. [ABSTRACT FROM AUTHOR]

The innovative technology of a marketable lab-on-a-chip platform for point-of-care (POC) in vitro detection has recently attracted remarkable attention. The POC tests can significantly enhance the high standard of medicinal care. In the last decade, clinical diagnostic technology has been broadly advanced and successfully performed in several areas. It seems that lab-on-a-chip approaches play a significant role in these technologies. However, high-cost and time-consuming methods are increasing the challenge and the development of a cost-effective, rapid and efficient method for the detection of biomolecules is urgently needed. Recently, polymer-coated sensing platforms have been a promising area that can be employed in medical diagnosis, pharmaceutical bioassays, and environmental monitoring. The designed on-chip sensors are based on molecular imprinting polymers (MIPs) that use label-free detection technology. Molecular imprinting shines out as a potentially promising technique for creating artificial recognition material with molecular recognition sites. MIPs provide unique advantages such as excellent recognition specificity, high selectivity, and good reusability. This review article aims to define several methods using molecular imprinting for biomolecules and their incorporation with several lab-on-chip technologies to describe the most promising methods for the development of sensing systems based on molecularly imprinted polymers. The higher selectivity, more user-friendly operation is believed to provide MIP-based lab-on-a-chip devices with great potential academic and commercial value in on-site clinical diagnostics and other point-of-care assays. • Lab-on-a-chip technology is the direct formation of progress in miniaturization. • Highly sensitive and selective MIP-based biosensors allow the sensing of biomarkers at low detection limits. • Surface modification is a very significant step in the design of biosensors. • MIPs are creative designs combined with lab-on-a-chip sensor devices. [ABSTRACT FROM AUTHOR]

In this study, heparin-imprinted poly(hydroxyethyl methacrylate-N-[(3-dimethylamino)-propyl] methacrylamide) cryogel column (HpMIP) was synthesized for removal of Hp from human plasma using molecular imprinting technique. Hp removal studies were performed from both aqueous solution and human plasma. Selectivity studies were performed using fast protein liquid chromatography (FPLC) system. The obtained results showed that the HpMIP column can remove Hp from both aqueous solutions and human plasma samples selectively. Ninety per cent of Hp was removed from 28 U/mL of human plasma samples successfully. Non-imprinted cryogel column (NIP) and plane PHEMA column were also synthesized to compare selectivity and non-specific adsorption properties. [ABSTRACT FROM PUBLISHER]

The objective of this study is to prepare imprinted cryogel discs for delivery of 5-fluorouracil. The coordinate bond interactions are utilized to accomplish a coordination complex between metal-chelate monomer N-methacryloyl- l -histidine and 5-FU with the assistance of Cu 2+ ion. The complex is copolymerized with hydroxyethyl methacrylate to produce poly(hydroxyethyl methacrylate-N-methacryloyl-( l )-histidine methyl ester) cryogel discs. The cryogel discs are characterized thoroughly by performing swelling tests, scanning electron microscopy, differential scanning calorimetry and X-ray diffraction studies. In vitro delivery studies are performed to investigate the effects of cross-linker ratio, medium pH and drug concentration. 5-FU imprinted cryogel discs have highly macroporous structures. Drug molecules are homogeneously dispersed in the 5-FU imprinted cryogel matrix. The cumulative release of 5-FU decreased by increasing the cross-linker density in the polymer matrix. Delivery rate of 5-FU varied with different pH values in a coordination complex since metal ion acts as a Lewis acid, and the ligand, i.e. 5-FU acts as a Lewis base. The cumulative release of 5-FU increased with increasing drug concentration in polymer matrix. The nature of the 5-FU transport mechanism is non-Fickian. [ABSTRACT FROM AUTHOR]

The purpose of this study is to synthesize megaporous cryogel loaded with hydrophobic affinity beads which can be utilized for the purification of lysozyme from chicken egg-white. N-methacryloyl-( l )-tryptophan methylester (MATrp) was used as the hydrophobic ligand. In the first step, poly(glycidyl methacrylate-N-methacryloyl-( l )-tryptophan methyl-ester) [PGMATrp] beads (2.2 μm in diameter) were produced by dispersion polymerization. In the second step, the poly(2-hydroxyethyl methacrylate) (PHEMA) cryogel loaded with PGMATrp beads [PHEMA/PGMATrp composite cryogel] was polymerized initiated by N,N,N′,N′-tetramethylene diamine (TEMED) and ammonium persulfate (APS) at −12 °C. Lysozyme adsorption capacity of the PHEMA/PGMATrp composite cryogel (332.7 mg/g polymer) was improved significantly due to the loading of PGMATrp beads into the cryogel structure. The hydrophobic MATrp comonomer played a vital role in this binding mechanism. The PHEMA/PGMATrp composite cryogel could be used many times without decreasing the lysozyme adsorption amount significantly. The main advantage of the PHEMA/PGMATrp composite cryogel is the high adsorption capacity. [ABSTRACT FROM AUTHOR]

A new approach, combining metal coordination with the molecular imprinting technique, was developed to prepare affinity materials. Magnetic poly(glycidyl methacrylate) microspheres in monosize form were used for specific recognition toward the target protein. The magnetic poly(glycidyl methacrylate) microspheres were prepared by dispersion polymerization in the presence of magnetite nanopowder. Surface imprinted magnetic poly(glycidyl methacrylate) microspheres based on metal coordination were prepared and used for the selective recognition of human serum albumin. Iminodiacetic acid was used as the metal coordinating agent and human serum albumin was anchored by Cu2+ ions on the surface of magnetic poly(glycidyl methacrylate) microspheres by metal coordination. The magnetic poly(glycidyl methacrylate) microspheres were coated with a polymer formed by condensation of tetraethyl orthosilicate and 3-aminopropyltrimethoxysilane. The human serum albumin imprinted magnetic poly(glycidyl methacrylate) microspheres were characterized by scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy and particle size analysis. The maximum adsorption capacity of human serum albumin imprinted magnetic poly(glycidyl methacrylate) microspheres was 37.7 mg/g polymer at pH 6.0. The selectivity experiments of human serum albumin imprinted magnetic poly(glycidyl methacrylate) microspheres prepared with different concentrations in the presence of lysozyme, bovine serum albumin and cytochrome C were performed in order to determine the relative selectivity coefficients. [ABSTRACT FROM AUTHOR]

Polymethacrylate based monolithic columns with weak cation exchange (WCX) properties were synthesized in fused silica capillary columns by capillary electrochromatography. Monolithic columns were prepared by in situ copolymerization of butyl methacrylate, ethylene dimethacrylate and N-methacryloyl-l-glutamic acid (MAGA) in a binary porogenic solvent composed of N,N-dimethyl formamide and phosphate buffer. The carboxyl groups provided by the monomer MAGA on the surface of the stationary phases generated the EOF from anode to cathode, and served as the WCX stationary phase at the same time. One of the originalities of this study was to make it clear the effect of MAGA as a novel weak cation exchange monomer in capillary columns. In this respect, in addition, the weak cation exchange character of MAGA, the effect of MAGA percentage on the electroosmotic mobility and column efficiency were investigated. The prepared columns were evaluated by SEM microphotographs and characterized with regard to the separation of alkyl benzenes. The monoliths prepared under optimized polymerization conditions were successfully characterized by using alkyl benzenes. The applied voltage was changed between 5 kV and 30 kV for separation of alkyl benzenes. The total analysis time of alkyl benzenes was shortened approximately tenfold (i.e. from 60 to 6 min). The synthesised monoliths contained ionizable carboxylic acid groups, which exhibited cation-exchange capability, that are useful for weak cation exchange chromatography. The applications of the optimized column were demonstrated using phenolic compounds and underivatized amino acids. The separation of phenolic compounds was achieved using a mobile phase consisting of 40/60% ACN/PB (10.0 mM, pH 7.0). The theoretical plate number up to 190 000 plates per m was achieved in the separation of phenols. The stability of the column was tested by conducting repeated analyses. [ABSTRACT FROM AUTHOR]

Binding interactions between Cibacron Blue‐F3GA (CB‐F3GA) and human serum albumin (HSA, at physiologically ten‐fold lower concentration) was studied by isothermal titration calorimetry (ITC) and in‐silico docking computations. ITC experiments revealed two separate binding sites on HSA with different binding affinities for CB‐F3GA. The high‐affinity binding site (PBS‐II) on HSA binds CB‐F3GA at nanomolar scale (KD1 = 118 ± 107 nM) with favorable binding enthalpy (ΔHo1 = − 6.47 ± 0.44 kcal/mol) and entropy (−TΔSo1 = −2.98 kcal/mol) energies. CB‐F3GA binds to the low‐affinity binding site (PBS‐I) at μM scale (KD2 = 31.20 ± 18.40 μM) with favorable binding enthalpy (ΔHo1 = − 5.03 ± 3.86 × 10−2 kcal/mol) and entropy (−TΔSo1 = −1.12 kcal/mol) energies. ITC binding data strongly suggest that CB‐F3GA binding to PBS‐II site increases the formation of dimeric‐HSA clusters (N1 = 2.43 ± 0.50), while binding to PBS‐I leads to tetrameric‐HSA clusters (N2 = 4.61 ± 0.90). These results suggest that a higher degree of HSA aggregation upon drug binding may be expected under physiological conditions, a notion that should be further investigated for the delivery and toxicity of drug−HSA interactions. [ABSTRACT FROM AUTHOR]

The purpose of this article is to synthesize poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-tryptophan) [mPHEMATrp] magnetic nanoparticles for lysozyme purification from chicken egg white. mPHEMATrp nanoparticles (38 nm in diameter) were synthesized by surfactant-free emulsion polymerization. Specific surface area of the mPHEMATrp nanoparticles was calculated to be 896 m²/g. Elemental analysis of mPHEMATrp nanoparticles was estimated in the range of 5.7-48.3 μmol MATrp/g. The maximum lysozyme adsorption capacity of the mPHEMATrp nanoparticles was 376.1 mg/g. The mPHEMATrp nanoparticles could be used five times without decreasing the lysozyme adsorption capacity significantly. The results indicate that the mPHEMATrp nanoparticles promise high selectivity for lysozyme purification. [ABSTRACT FROM AUTHOR]

ABSTRACT This article describes the development of a polybutylmethacrylate-based monolithic capillary column as a chiral stationary phase. The chiral monolithic column was prepared by of (BMA), (EDMA), and (MAGA) in the presence of porogens. The porogen mixture included and phosphate buffer. MAGA was used as a chiral selector. The effect of MAGA content was investigated on electrochromatographic enantioseparation of d,l-histidine, , , and d,l-glutamic acid. The effect of acetonitrile (ACN) content in mobile phase on electro-osmotic flow was also investigated. It was demonstrated that the poly(BMA-EDMA-MAGA) monolithic chiral column can be used for the electrochromatographic enantioseparation of amino acids by (CEC). The mobile phase was ACN/10 mM phosphate buffer (45:55%) adjusted to pH 2.7. It was observed that l-enantiomers of the amino acids migrated before d-enantiomers. The separation mechanism of electrochromatographic enantioseparation of amino acids in CEC is discussed. Chirality 24:606-609, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: A monolithic cryogel column was prepared to obtain an efficient, cost effective and rapid purification of cytochrome c from rat liver homogenate. N-Methacryloyl-(l)-histidine methyl ester (MAH) was used as the metal-chelating ligand. Poly(hydroxyethyl methacrylate-N-methacryloyl-(l)-histidine methyl ester) [PHEMAH] monolithic cryogel was produced by free radical polymerization initiated by N,N,N′,N′-tetramethylene diamine (TEMED) and ammonium persulfate (APS) pair in an ice bath. PHEMAH cryogel was characterized by surface area measurements, swelling studies, scanning electron microscopy and elemental analysis. The PHEMAH cryogel had a specific surface area of 38.6m2/g. The PHEMAH cryogel containing 113.7μmol MAH/g was complexed with the Cu2+ ions directly via MAH for the adsorption of cytochrome c from aqueous solutions and rat liver homogenate. The cytochrome c adsorption on the PHEMAH cryogel was 3.1mg/g. The maximum cytochrome c adsorption capacity of the Cu2+-chelated PHEMAH cryogel (carrying 58.7μmol Cu2+ per gram of polymer) was found to be 20.8mg/g at pH 8.0 in phosphate buffer. The cytochrome c adsorption amount from rat liver homogenate was 37.7mg/g with a purity of 93.8%. It was observed that cytochrome c could be repeatedly adsorbed and eluted with the PHEMAH cryogel without significant loss in the adsorption capacity. [Copyright &y& Elsevier]

Abstract: Monosize and magnetic poly(glycidyl methacrylate-N-methacryloyl-(l)-tryptophan) [mPGMATrp] beads (1.6 µm in diameter) were used for hydrophobic affinity capture of lysozyme from chicken egg-white. N-methacryloyl-(l)-tryptophan (MATrp), which gives hydrophobicity to the resulting polymer, was synthesized by reacting methacryloyl chloride and l-tryptophan methyl ester then characterized by Nuclear Magnetic Resonance (NMR). mPGMATrp beads were produced by dispersion polymerization in the presence of magnetite nano-powder. mPGMATrp beads were characterized by means of swelling studies, elemental analysis, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). Lysozyme adsorption experiments were performed under different experimental conditions (i.e., lysozyme concentration, temperature, and ionic strength) in magnetically stabilized fluidized bed system, (MSFB). Maximum adsorption capacity was 263.9 mg/g. It was observed that mPGMATrp beads can be used without significant loss in lysozyme adsorption capacity after 25 adsorption-elution cycle. [Copyright &y& Elsevier]

Abstract: Molecular imprinting polymer (MIP) as a recognition element for sensors are increasingly of interest and MIP-SPR have started to appear in the literature. In this study, we have proposed a novel surface imprinting method for DNA recognition and determination by methacryl-amidohistidine-platinum(II) [MAH-Pt(II)] as a new metal-chelating monomer via metal coordination–chelation interactions and guanosine/guanine templates of DNA. The study includes the measurement of binding interaction of molecular imprinted surface plasmon resonance (SPR) sensor via ligand interaction and recognition selectivity studies of guanosine and guanine imprinted polymers with respect to guanine and dsDNA. Adsorption isotherms of adenosine, guanosine, guanine, adenine, ssDNA and dsDNA were plotted and affinity constants for guanosine and guanine imprinted films were also calculated. [Copyright &y& Elsevier]

Abstract: Brewer''s yeast (bottom yeast, Saccharomyces cerevisiae subsp. uvarum) cells were magnetically modified using water based magnetic fluid stabilized perchloric acid. The magnetically modified yeast cells were characterized by scanning electron microscopy (SEM) and electron spin resonance (ESR). Hg2+ biosorption-desorption properties of magnetically modified yeast cells from synthetic solutions were utilized in batch system. The biosorption process was fast; 80% of biosorption occured within 60min and equilibrium was achieved at around 90min. The maximum Hg2+ biosorption capacity was obtained to be 114.6mg/g at 35°C. The suitability of the Langmuir, Freundlich and Redlich-Peterson adsorption models to the equilibrium data was investigated for mercury-biosorbent system. The results were well fitted to the Langmuir isotherm. The applicability of two kinetic models including pseudo-first order and pseudo-second order model was estimated on the basis of comparative analysis of the corresponding rate parameters, equilibrium capacity and correlation coefficients. Results suggest that chemisorption processes could be the rate-limiting step in the biosorption process. The yeast biomass can be easily regenerated by 0.1M HNO3 with higher effectiveness. Biosorption of heavy metal ions from artificial wastewater was also studied. The biosorption capacities are 29.9mg/g for Cu2+, 76.2mg/g for Hg2+, 14.1mg/g for Ni2+ and 11.8mg/g for Zn2+. [Copyright &y& Elsevier]

Human serum albumin (HSA)-immobilised magnetic poly(2-hydroxyethyl methacrylate) (mPHEMA) particles were investigated as an adsorbent for selective bilirubin removal from human plasma in a magnetically stabilized fluidized bed system. mPHEMA particles were prepared by suspension polymerization in the presence of Fe3O4 particles. mPHEMA particles were characterized by scanning electron microscopy (SEM), surface area and pore size measurements. The mPHEMA beads have a spherical shape and porous structure. The specific surface area of the mPHEMA particles was found to be 50 m2/g with a size range of 80–120 μm in diameter and the swelling ratio was 45%. Then, HSA was covalently coupled to the cyanogen bromide (CNBr)-activated mPHEMA particles. The amount of coupled HSA was arranged by changing the activation degree of particles (i.e., CNBr concentration). In vitro bilirubin removal was investigated from hyperbilirubinemic human plasma on the mPHEMA particles containing different amounts of immobilised HSA (between 11 and 100 mg/g). The non-specific bilirubin adsorption on the bare mPHEMA particles was 0.47 mg/g. Higher bilirubin adsorption capacities, up to 88.3 mg/g, were obtained with the HSA-immobilised magnetic particles. Bilirubin capacity decreased significantly from 75.0 mg/g to 40.0 mg/g polymer with the increase of the flow-velocity from 0.5 ml/min to 4.0 ml/min. Bilirubin adsorption increased with increasing temperature. Adsorption behavior of bilirubin could be modelled using the Langmuir isotherm. [ABSTRACT FROM AUTHOR]

Abstract: Cibacron Blue F3GA was covalently attached onto monosize poly(glycidyl methacrylate) [poly(GMA)] beads for purification of lysozyme from chicken egg white. Monosize poly(GMA) beads, 1.6μm in diameter, were produced by a dispersion polymerization technique. The content of epoxy groups on the surface of the poly(GMA) sample determined by the HCl–pyridine method (3.8mmol/g). Cibacron Blue F3GA loading was 1.73mmol/g. The monosize beads were characterized by elemental analysis, FTIR and SEM. Adsorption studies were performed under different conditions in a batch system (i.e., medium pH, protein concentration, temperature and ionic strength). Maximum lysozyme adsorption amount of poly(GMA) and poly(GMA)-Cibacron Blue F3GA beads were 1.6 and 591.7mg/g, respectively. The applicability of two kinetic models including pseudo-first order and pseudo-second order model was estimated on the basis of comparative analysis of the corresponding rate parameters, equilibrium adsorption capacity and correlation coefficients. Results suggest that chemisorption processes could be the rate-limiting step in the adsorption process. It was observed that after 10 adsorption–elution cycle, poly(GMA)-Cibacron Blue F3GA beads can be used without significant loss in lysozyme adsorption capacity. Purification of lysozyme from egg-white was also investigated. Purification of lysozyme was monitored by determining the lysozyme activity using Micrococcus lysodeikticus as substrate. The purity of the eluted lysozyme was analyzed by SDS-PAGE and found to be 88% with recovery about 79%. The specific activity of the eluted lysozyme was high as 43,600U/mg. [Copyright &y& Elsevier]

Abstract: Cibacron Blue F3GA was covalently attached onto monosize poly(glycidyl methacrylate) [poly(GMA)] beads for removal of human serum albumin (HSA) from human serum. Monosize poly(GMA) beads, 1.6μm in diameter, were produced by dispersion polymerization. Cibacron Blue F3GA loading was 1.73mol/g. HSA adsorption experiments were performed by stirred-batch adsorption. The non-specific adsorption of HSA was low (0.8mg/g polymer). Dye attachment onto the monosize beads significantly increased the HSA adsorption (189.8mg/g). The maximum HSA adsorption was observed at pH 5.0. With an increase of the aqueous phase concentration of sodium chloride, the adsorption capacity decreased drastically. The equilibrium adsorption of HSA significantly decreased with increasing temperature. The elution studies were performed by adding 0.1M Tris/HCl buffer containing 0.5M NaSCN to the HSA solutions in which adsorption equilibria had been reached. The elution results demonstrated that the adsorption of HSA to the adsorbent was reversible. The depletion efficiencies for HSA were above 87% for all studied concentrations. To test the efficiency of HSA removal from human serum, proteins in the serum and eluted portion were analyzed by two-dimensional gel electrophoresis. Eluted proteins include mainly albumin, and a small number of nonalbumin proteins such as apo-lipoprotein A1, sero-transferrin, haptoglobulin and α1-antitrypsin were bound by the dye-affinity beads. IgA was not identified in eluted fraction. [Copyright &y& Elsevier]

Abstract: Poly(Hydroxyethylmethacrylate–Ethyleneglycoldimethacrylate), poly(HEMA–EGDMA), microbeads with 150–200μm in size, was prepared by suspension polymerization. β-cyclodextrin was modified onto the polymeric microbeads using glutaraldahyde activation in an acidic medium at pH=2.5. FT-IR and TGA were used for the characterization of modified polymers and the determination of the nature of the interaction between phenolic compounds and the modified polymeric microbeads. Plain and β-cyclodextrin modified microbeads were used in adsorption–desorption studies of phenolic species in single solution. Adsorption capacities of the phenolic species onto the plain microbeads were found to be 28.2, 17.0, 14.3, 9.8, and 1.92mg/g polymer for o-chloro phenol, p-nitro phenol, p-chloro phenol, o-nitro phenol, and phenol, respectively. However, for β-cyclodextrin modified microbeads, adsorption capacity of phenolic species was determined as 274, 365, 128, 182, and 87mg/g for phenol, o-nitro phenol, p-nitro phenol, o-chloro phenol, and p-chloro phenol, respectively. Desorption ratio for the phenolic species was more than 90%, except for o-nitro phenol. Detection limits of the phenolic species were improved at least 500-fold for UV–Vis spectrophotometric detection, after the pre-concentration of all phenolic species used in this study. Adsorption time for the phenolic species onto β-cyclodextrin-modified poly(HEMA–EGDMA) microbeads was found to be reasonable short (10–60min) and suitable for the applications. Also, synthesized microbeads were useful for the repeated use for the removal and pre-concentration of phenolic species. [Copyright &y& Elsevier]

Abstract: N-methacryloyl-(l)-glutamic acid (MAGA) was synthesized using methacryloyl chloride and l-glutamic acid methyl ester as a metal-complexing ligand and/or comonomer. MAGA was characterized by FTIR and NMR. Spherical beads with an average diameter of 150–200 μm were obtained by suspension polymerization of MAGA and 2-hydroxyethyl methacrylate (HEMA) performed in an aqueous dispersion medium. Poly(HEMA-MAGA) beads were characterized by swelling studies, surface area measurements and elemental analysis. Poly(HEMA-MAGA) beads have a specific surface area of 56.7 m2/g. Poly(HEMA-MAGA) beads were used in the removal studies of Pb2+ ions. Adsorption equilibrium was achieved in about 60 min. The adsorption of Pb2+ ions onto PHEMA beads was negligible (0.38 mg/g). The MAGA incorporation into the polymer structure significantly increased the lead adsorption capacity (348 mg/g). The adsorption of Pb2+ ions increased with increasing pH and reached a plateau value at around pH 5.0. Competitive adsorption of heavy metal ions from synthetic wastewater was also studied. The adsorption capacities are 42.5 mg/g for Pb2+, 26.8 mg/g for Hg2+ and 17.6 mg/g for Cd2+ at 0.5 mmol/l metal concentration. Consecutive adsorption and elution operations showed the feasibility of repeated use for poly(HEMA-MAGA) chelating beads. [Copyright &y& Elsevier]

Abstract: Molecular imprinted polymers (MIP) as a recognition element for sensors are increasingly of interest and MIP–quartz crystal microbalance (QCM) have started to appear in the literature. In this study, we have combined quartz crystal microbalance with MIP to prepare a sensor using the ability of glucose to chelate of copper (II) ion of methacrylamidohistidine (MAH) monomer to create ligand exchange (LE) assembled monolayer which is suitable for glucose determination. The study includes the measurement of binding interaction of molecularly imprinted QCM sensor via ligand interaction, investigation of the pH effect on frequency shift and recognition selectivity studies of glucose-imprinted polymer with respect to methyl-α-d-glucopyranoside and sucrose. Bmax (number of binding sites) and KD (dissociation constant of the metal–chelate copolymer) were also calculated using Scathard plot and the detection limit was found as 0.07mM. MIP showed higher glucose-binding affinity than a well-known glucose binding protein, conconavalin A. [Copyright &y& Elsevier]

In this study, the potential use of the fungus Pleurotus sajor caju to remove phenols (i.e., phenol, o-chlorophenol, p-chlorophenol and 2,4,6-trichlorophenol) from aqueous solutions was evaluated. Biosorption of phenol or chlorophenols reached equilibrium in 4 h. The maximum adsorptions of phenol and chlorophenols onto the Pleurotus sajor caju were 0.95 mmol/g for phenol, 1.24 mmol/g for o-chlorophenol, 1.47 mmol/g for p-chlorophenol and 1.89 mmol/g for 2,4,6-trichlorophenol. The affinity order was as follows: 2,4,6-trichlorophenol > p-chlorophenol > o-chlorophenol > phenol. Phenol and chlorophenols bindings onto Pleurotus sajor caju were clearly pH dependent. The adsorption of phenol and chlorophenols increased with increasing pH. Desorption was achieved using methanol solution (30%, v/v). Pleurotus sajor caju biomass is suitable for reuse for more than five cycles without noticeable loss of adsorption capacity. [Copyright &y& Elsevier]

The potential use of the fungus Phanerochaete chrysosporium to remove chlorophenols (phenol, o-chlorophenol, p-chlorophenol and 2,4,6-trichlorophenol) from aqueous solutions was evaluated. The kinetics of both adsorption and desorption of phenolic compounds was rapid for all adsorbates. The maximum adsorptions of phenol and chlorophenols onto the Phanerochaete chrysosporium were 1.23 mmol/g for phenol, 1.49 mmol/g for o-chlorophenol, 1.78 mmol/g for p-chlorophenol and 2.14 mmol/g for 2,4,6-trichlorophenol. The affinity order was as follows: 2,4,6-trichlorophenol > p-chlorophenol > o-chlorophenol > phenol. Phenol and chlorophenols binding with Phanerochaete chrysosporium were clearly pH dependent. The adsorption of phenol and chlorophenols increased as pH increased. Desorption of phenol or chlorophenols was achieved using methanol solution (30% (v/v)). Phanerochaete chrysosporium is suitable for reuse for more than ten cycles without noticeable loss of adsorption capacity. [Copyright &y& Elsevier]

This work describes a method for the removal of phenolic compounds with a nitrophenol-imprinted polymer from aqueous solution by newly functional monomer, methacrylamidoantipyrine (MAAP), which has π–π and hydrogen-bonding interactions. Nitrophenol-imprinted polymers were prepared in a bulk, photo-initiated polymerization by the methods of MAAP which has both π–π and hydrogen-bonding interactions and methacrylic acid (MAA) which only has hydrogen bonding, imprinting. The adsorption capacity for nitrophenol and other phenolic compounds onto molecularly imprinted adsorbents (MIPs) was found to significantly depend on the use of functional monomers. The maximum adsorptions of phenolic compounds onto imprinted beads were 173 μmol/g for MAAP and 97 μmol/g for MAA-based imprinted polymers. The pH significantly affected the adsorption capacity of MIPs. The selectivities were measured by comparing the relative selectivity coefficient under competetive adsorption conditions. [Copyright &y& Elsevier]

A novel metal-chelate adsorbent utilizing N-methacryloyl-(l)-histidine methyl ester (MAH) as a metal-chelating ligand was prepared. MAH was synthesized by using methacryloyl chloride and l-histidine methyl ester dihydrochloride. Magnetic beads with an average size of 150–250 μm were obtained by suspension polymerization of ethylene glycol dimethacrylate (EGDMA), and MAH conducted in aqueous dispersion medium. The specific surface area of the porous beads was found to be 80.1 m2/g. Mag-poly(EGDMA–MAH) beads were characterized by swelling tests, electron spin resonance (ESR), nuclear magnetic resonance (NMR) and scanning electron microscopy (SEM). Elemental analysis of MAH for nitrogen was estimated as 43.9 μmol/g. Then, Fe3+ ions were chelated on the magnetic beads. Fe3+-chelated magnetic beads with a swelling ratio of 40% were used in the adsorption of catalase in batch system. The maximum catalase adsorption capacity of the mag-poly(EGDMA–MAH)–Fe3+ beads was observed as 83.2 mg/g at pH 7.0. The Km values for immobilized catalase (mag-poly(EGDMA–MAH)–Fe3+) (20.5 mM) were higher than that of free enzyme (16.5 mM). Storage stability was found to increase with immobilization. It was observed that enzyme could be repeatedly adsorbed and desorbed without significant loss in adsorption capacity or enzyme activity. [Copyright &y& Elsevier]

A novel approach was developed to obtaining high uranium adsorption capacity utilizing 2-methacryloylamidoglutamic acid (MAGA) as a metal-complexing ligand. MAGA was synthesized by using methacryloyl chloride and glutamic acid. Spherical beads with an average size of 150–200 μm were obtained by suspension polymerization of MAGA and 2-hydroxyethyl methacrylate (HEMA) conducted in an aqueous dispersion medium. Poly(2-hydroxyethyl methacrylate–methacryloylamidoglutamic acid) [p(HEMA–MAGA)] beads have a specific surface area of 56.7 m2/g. p(HEMA–MAGA) beads were characterized by swelling studies, FTIR and elemental analysis. The p(HEMA–MAGA) beads with a swelling ratio of 63%, and containing 3.5 mmol MAGA/g were used in the removal of UO22+ from aqueous solutions. Adsorption equilibrium was achieved in about 120 min. The adsorption of uranium(VI) ions onto pHEMA was negligible (1.4 mg/g). The MAGA incorporation significantly increased the uranium adsorption capacity (204.8 mg/g). Adsorption capacity of MAGA incorporated beads increased significantly with pH and then reached the maximum at pH 6.0. Consecutive adsorption and elution operations showed the feasibility of repeated use for p(HEMA–MAGA) chelating beads. [Copyright &y& Elsevier]

Metal-chelating ligand and/or comonomer 2-methacrylolyamidohistidine (MAH) was synthesized by using methacryloyl chloride and l-histidine methyl ester. MAH was characterized by NMR and FTIR. Spherical beads with an average diameter of 75–125 μm were produced by suspension polymerization of methylmethacrylate (MMA) and MAH carried out in an aqueous dispersion medium. Poly(MMA-MAH) beads had a specific surface area of 37.5 m2/g. Poly(MMA-MAH) beads were characterized by water uptake studies, FTIR, SEM and elemental analysis. Elemental analysis of MAH for nitrogen was estimated as 34.7 μmol/g of polymer. Then, Cu2+ ions were chelated on the beads. Cu2+-chelated beads with a swelling ratio of 38% were used in the adsorption of human-immunoglobulin G (HIgG) from both aqueous solutions and human plasma. The maximum adsorption capacities of the Cu2+-chelated beads were found to be 12.2 mg/g at pH 6.5 in phosphate buffer and 15.7 mg/g at pH 7.0 in MOPS. Higher adsorption value was obtained from human plasma (up to 54.3 mg/g) with a purity of 90.7%. The metal-chelate affinity beads allowed one-step separation of HIgG from human plasma. The adsorption–desorption cycle was repeated 10 times using the same beads without noticeable loss in their HIgG adsorption capacity. [Copyright &y& Elsevier]

Poly(hydroxyethyl methacrylate) (PHEMA) beads (in the size range of 150–200 μm) with good mechanical properties were prepared and crosslinked with ethylene glycol dimethacrylate (EGDMA) to increase their chemical stability. Because of their hydroxyl groups, they can serve as affinity adsorbent and can be employed for medical applications. Cibacron Blue F3GA was succesfully immobilized onto the beads. The maximum dye attachment was 16.5 μmol/g. Then, metallopeptide-ligand cysteinylhexapeptide (CysHP) was incorporated onto these beads and they were used for removal of cadmium ions [Cd(II)] from human plasma in a packed-bed column. The maximum amount of CysHP attached was 3.2 mg/g. Non specific Cd(II) adsorption from human plasma on the PHEMA beads was 0.32 mg/g. The adsorption capacity of the beads decreased from 11.8 to 3.7 mg/g with the raise of the flow-rate from 1.0 to 5.0 ml/min. It has been found that the CysHP loading has a great effect on the capacity of beads for adsorbing Cd(II) ions from human plasma. This suggests that these modified beads could be used for removal of Cd(II) ions from human plasma. [ABSTRACT FROM AUTHOR]

Anti-low density lipoprotein antibody (anti-LDL antibody) attached poly(2-hydroxyethyl methacrylate-methacryloylamidophenylalanine) (poly(HEMA-MAPA)) beads were prepared for selective removal of cholesterol from hypercholesterolemic human plasma. Poly(HEMA-MAPA) beads were produced by a modified suspension polymerization and then characterized by swelling tests and SEM. Blood-compatibility tests were also investigated. The water swelling ratio of the poly(HEMA-MAPA) beads increased significantly (68%) compared with pHEMA (55%). All the clotting times increased when compared with poly(HEMA) beads. Loss of platelets and leukocytes was very low. The maximum anti-LDL antibody attachment was achieved at pH 7.0. Attachment of anti-LDL antibody was 29.6 mg/g. There was a very low non-specific cholesterol binding onto the poly(HEMA-MAPA) beads, about 0.74 mg/g. Anti-LDL antibody attached beads adsorbed in the range of 13.3-16.0 mg cholesterol/g from hypercholesterolemic human plasma. Up to 92% of the adsorbed LDL was desorbed. The binding-elution cycle was repeated 10 times using the same beads. There was no significant loss of binding capacity. [ABSTRACT FROM AUTHOR]

In this study, the Hg2+ adsorption–desorption properties of poly(ethyleneimine) (PEI)-attached poly(2-hydroxyethylmethacrylate) (PHEMA) beads were investigated. Spherical PHEMA beads with an average size of 150–200 μm were obtained by suspension polymerization of 2-hydroxyethylmethacrylate conducted in an aqueous dispersion medium. Owing to the reasonably rough character of the bead surface, PHEMA beads had a specific surface area of 14.8 m2/g. PEI chains could be covalently attached onto the PHEMA beads with equilibrium binding capacities up to 50 mg PEI/g beads. PEI-attached PHEMA beads were utilized as adsorbent in the adsorption–desorption of Hg2+ ions from synthetic solutions. The adsorption process was fast; 90% of adsorption occurred within 45 min and equilibrium was reached at around 1 h. The maximum Hg2+ adsorption capacity obtained was 1.67 mmol/g at a pH of about pH 5.0. Adsorption behavior can be described at least approximately by the Langmuir equation. The metal-chelating beads can be easily regenerated by 0.1 M HNO3 with higher effectiveness. Adsorption of heavy metal ions from artificial wastewater was also studied. The adsorption capacities were 1.32 mmol/g for Hg2+, 0.34 mmol/g for Ni2+ and 0.42 mmol/g for Cu2+. [Copyright &y& Elsevier]

Since the discovery of the implication of aluminium in dialysis encephalopathy, much progress has been made in the preparation of dialysis water from which the metal is now virtually excluded. In this study, Alizarin Yellow-attached magnetic poly(2-hydroxyethyl methacrylate) (mPHEMA) beads were investigated as a specific adsorbent for aluminium removal from both drinking and dialysis water. Magnetic PHEMA beads in the size range of 80–120 μm were produced by a dispersion polymerization technique. Then Alizarin Yellow was covalently attached onto mPHEMA beads. Al(III) adsorption from aqueous solutions was examined in a batch system. Alizarin Yellow-attached mPHEMA beads were characterized by scanning electron microscopy (SEM) and elemental analysis. The mPHEMA beads have a spherical shape and porous structure. Alizarin Yellow loading was found to be 208 μmol/g polymer. Non-specific Al(III) adsorption was about 23 μmol/g polymer. Alizarin loading greatly improved the adsorption capacity (420 μmol/g polymer). The maximum Al(III) adsorption was observed at pH 5.0. Adsorption capacity of the Alizarin Yellow-attached beads from drinking and dialysis water for Al(III) ions was higher than that for other ions (i.e. Cu(II), Fe(III) and Zn(II)). More than 90% of the adsorbed Al(III) ions were desorbed successfully using 2.0 M HNO3 solution. It was possible to reuse these Alizarin Yellow-attached mPHEMA beads without significant losses in the Al(III) adsorption capacities. [Copyright &y& Elsevier]

Different metal-complexing ligands carrying synthetic and natural adsorbents have been reported in the literature for heavy metal removal. We have developed a novel and new approach to obtain high metal adsorption capacity utilizing 2-methacryloylamidocysteine (MAC) as a metal-complexing ligand and/or comonomer. MAC was synthesized by using methacryloyl chloride and cysteine. Spherical beads with an average size of 150–200 μm were obtained by the radical suspension polymerization of MAC and 2-hydroxyethylmethacrylate (HEMA) conducted in an aqueous dispersion medium. Poly(2-hydroxyethylmethacrylate–methacryloylamidocysteine) p(HEMA–MAC) beads have a specific surface area of 18.9 m2 g−1. p(HEMA–MAC) beads were characterized by swelling studies, FTIR and elemental analysis. The p(HEMA–MAC) beads with a swelling ratio of 72%, and containing 3.9 mmol MAC g−1 were used in the removal of cadmium(II) ions from aqueous solutions. Adsorption equilibrium was achieved in about 15 min. The adsorption of Cd(II) ions onto pHEMA beads was negligible. The MAC incorporation significantly increased the Cd(II) adsorption capacity. Adsorption capacity of MAC incorporated beads increased significantly with pH. Competitive heavy metal adsorption from aqueous solutions containing Cd(II), Cr(III), Pb(II), Hg(II) and As(III) was also investigated. The adsorption capacities are 254 mg g−1 for Cd(II); 90.9 mg g−1 for Cr(III); 150.4 mg g−1 for Hg(II), 91.2 mg g−1 for Pb(II) and 6.7 mg g−1 for As(III) ions. These results are an indication of higher specificity of the p(HEMA–MAC) beads for the Cd(II) ions compared with other ions. Consecutive adsorption and desorption operations showed the feasibility of repeated use for p(HEMA–MAC) chelating beads. [Copyright &y& Elsevier]

Anti-low density lipoprotein antibody (anti-LDL) immobilized polyhydroxyethylmethacrylate (pHEMA) based membrane was prepared for selective removal of cholesterol from hypercholesterolemic human plasma. In order to further increase blood-compatibility, a newly synthesized comonomer, methacryloylamidophenylalanine (MAPA) was included in the membrane formulation. p(HEMA–MAPA) membranes were produced by a photopolymerization and then characterized by swelling tests, SEM and contact angle studies. Blood-compatibility tests were also investigated. The water swelling ratio of the p(HEMA–MAPA) membrane increases significantly (133.2.9%) compared with pHEMA (58%). p(HEMA–MAPA) membranes have large pores around in the range of 5–10 μm. All the clotting times increased when compared with pHEMA membranes. Loss of platelets and leukocytes was very low. The maximum anti-LDL antibody immobilization was achieved around pH 7.0. Immobilization of anti-LDL antibody was 12.6 mg/ml. There was a very low non-specific cholesterol adsorption onto the plain p(HEMA–MAPA) membranes, about 0.36 mg/ml. Anti-LDL antibody immobilized membranes adsorbed in the range of 4.5–7.2 mg cholesterol/ml from hypercholesterolemic human plasma. Up to 95% of the adsorbed LDL antibody was desorbed. The adsorption–desorption cycle was repeated 10 times using the same membrane. There was no significant loss in the adsorption capacity. [Copyright &y& Elsevier]

A white rot fungus species Lentinus sajor-caju biomass was entrapped into alginate gel via a liquid curing method in the presence of Ca(II) ions. The biosorption of cadmium(II) by the entrapped live and dead fungal biomass has been studied in a batch system. The heat-treatment process enhanced the biosorption capacity of the immobilized fungal biomass. The effect of initial cadmium concentration, pH and temperature on cadmium removal has been investigated. The maximum experimental biosorption capacities for entrapped live and dead fungal mycelia of L. sajur-caju were found to be 104.8±2.7 mg Cd(II) g−1 and 123.5±4.3 mg Cd(II) g−1, respectively. The kinetics of cadmium biosorption was fast, approximately 85% of biosorption taking place within 30 min. The biosorption equilibrium was well described by Langmuir and Freundlich adsorption isotherms. The change in the biosorption capacity with time is found to fit pseudo-second-order equations. Cadmium binding properties of entrapped fungal preparations have been determined applying the Ruzic equations. Since the biosorption capacities are relatively high for both entrapped live and dead forms, they could be considered as suitable biosorbents for the removal of cadmium in wastewater treatment systems. The biosorbents were reused in three consecutive adsorption/desorption cycles without significant loss in the biosorption capacity. [Copyright &y& Elsevier]

Aluminium has recently been considered as a causative agent in dialysis encephalopathy, osteodystrophy, and anemia occuring in hemodialysis patients. The aim of this study is to prepare magnetic poly(2-hydroxyethylmethacrylate) (mPHEMA) adsorbent and to investigate it's useability for the removal of Al(III) ions from drinking and dialysis water. Magnetic PHEMA beads in a size range 80-120 μm were produced by a dispersion polymerization technique. Then Alizarin Red was covalenlty attached onto the mPHEMA beads. Al(III) adsorption from aqueous solutions was examined by batch system. mPHEMA beads were characterized by swelling tests, electron spin resonance (ESR), scanning electron microscopy (SEM), and elemental analysis. Important results obtained in this study are as follows: the swelling ratio of mPHEMA beads was 34%. The presence of magnetite in the polymeric structure was confirmed by ESR. The mPHEMA beads have a spherical shape and porous structure. Alizarin Red loading was 135.8 μmolg[sup -1] polymer. The maximum Al(III) adsorption was 722 μmol g[sup -1] polymer at pH 5.0. Non-specific Al(III) adsorption was about 23 μmolg[sup -1] polymer under the same conditions. High desorption ratios (98%) were achieved by using 0.1 M HNO3. It was possible to reuse the beads without significant loss of Al(III) adsorption capacity. [ABSTRACT FROM AUTHOR]

The abilities of various sorbent materials for heavy metal removal have been reported in the literature. We have developed a novel approach to obtain high metal-sorption capacity utilizing a membrane containing 2-methacrylamidophenylalanine. Metal-complexing ligand 2-methacrylamidophenylalanine (MAPA) was synthesized through the use methacrylo chloride and phenylalanine. Then, poly(2-hydroxyethylmethacrylate-co-2-methacrylamidophenylalanine) (p(HEMA-co-MAPA)) membranes were prepared by UV-initiated photopolymerization of HEMA and MAPA in the presence of the initiator azobisisobutyronitrile. MAPA monomer was characterized by nuclear magnetic resonance spectroscopy. p(HEMA-co-MAPA) membranes were characterized by swelling studies, scanning electron microscopy, Fourier transform infrared spectroscopy, and elemental analysis. These membranes have large pores; the micropore dimensions are approximately 5–10 μm. p(HEMA-co-MAPA) affinity membranes with a swelling ratio of 133.2% and containing 18.9 mmol MAPA/m2 were used in the removal of the heavy-metal ions of copper, nickel, and mercury from aqueous media containing different amounts of these ions (5–600 mg/L) and at different pH values (2.0–7.0). The maximum adsorption capacities of heavy metal ions onto the MAPA-containing membranes under noncompetitive conditions were 23.8 mmol/m2 for Cu(II), 29.1 mmol/m2 for Ni(II), and 50.3 mmol/m2 for Hg(II). The affinity order was Hg(II) > Ni(II) > Cu(II).The adsorption of heavy metal ions increased with increasing pH and reached a plateau value at approximately pH 5.0. Adsorption of heavy metal ions from artificial wastewater was also studied. The adsorption capacities were 11.9 mmol/m2 for Cu(II), 7.33 mmol/m2 for Ni(II), and 9.79 mmol/m2 for Hg(II). Desorption of heavy metal ions was performed using 0.1 M HNO3. The p(HEMA-co-MAPA) membranes are suitable for more than five cycles without noticeable loss of capacity. [ABSTRACT FROM AUTHOR]

Magnetic polymethylmethacrylate [mPMMA] microbeads (150-200 μm in diameter) carrying hexamethylene diamine (HMDA) were prepared for the removal of Pb(II) ions from aqueous solutions containing different amounts of Pb(II) ions (5–100 mg/L) and at different pH values (2.0–6.0). Adsorption rates were observed as high at the beginning of the adsorption process, and then equilibrium was reached in about 20 minutes. Adsorption of Pb(II) ions on the unmodified mPMMA microbeads was negligible (4.2 μmol/g). While HMDA-incorporation significantly increased the Pb(II) adsorption was (128 μmol/g). The adsorption of Pb(II) ions increased with an increasing pH, and reached a plateau value at around pH 5.0. The optimal pH range for Pb(II) removal was shown to be from 5.0 to 6.0. Desorption of Pb(II) ions was achieved using 0.1 M HNO3. The maximum desorption value was as high as 98%. These microbeads are suitable for repeated use for more than five adsorption-desorption cycles without a considerable loss of adsorption capacity. [ABSTRACT FROM AUTHOR]

The triazine dye Cibacron Blue F3GA was covalently immobilized as an affinity ligand onto microporous poly(2-hydroxyethyl methacrylate) (pHEMA) membranes. Three different metal ions [i. e., Fe(III), Zn(II), or Cu(II)] were then chelated with the immobilized Cibacron Blue F3GA molecules. Lysozyme adsorption onto these affinity adsorbents from aqueous solutions containing different amounts of lysozyme at different pH was investigated in a batch system. Lysozyme adsorption capacity of all of the metal-dye-immobilized membranes was greater than that of the dye-immobilized membranes. The nonspecific adsorption of the protein on the pHEMA membranes was negligible. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The maximum capacity (qm) of the Fe(III)–Zn(II),–or Cu(II)–dye chelated membranes for lysozyme adsorption (384, 326, and 306 μg/cm2) was greater than that of the dye-immobilized membrane (224 μg lysozyme/cm2), respectively. The dissociation constant (kd) values were found to be 2.51 × 10-7 M with dye-immobilized membrane, and 2.32 ×10-7×10-7and 2.40 ×10-7 M with the Fe(III)–Zn(II),–and Cu(II)–dye-chelated membranes, respectively. More than 95% of the adsorbed lysozyme was desorbed in 60 min in the desorption medium containing 0.5 M KSCN at pH 8.0. [ABSTRACT FROM AUTHOR]

Microporous membranes made of poly(2-hydroxyethylmethacrylate) [poly(HEMA)] carrying protein A were used for selective sorption of human-IgG from human plasma. Poly(HEMA) membranes were prepared by a photo-polymerization technique, and activated by cyanogen bromide (CNBr) in an alkaline medium (pH 11.5). Bioligand protein A was then immobilized by covalent binding onto these CNBr-activated membranes. The amount of immobilized protein A was controlled by changing pH and the initial concentrations of CNBr and protein A. The non-specific adsorption of protein A on the plain poly(HEMA) membranes was 2.9 μg cm[sup -2]. Maximum protein A immobilization was observed at pH 9.5. Up to 186 μg cm[sup -2] was immobilized on the CNBr-activated poly(HEMA) membranes. The maximum adsorption of human-IgG on the protein A-immobilized poly(HEMA) membranes was observed at pH 8.0. The non-specific adsorption of human-IgG onto the plain poly(HEMA) membranes was low (about 4.4 μg cm[sup -2]). Higher human-IgG adsorption values (up to 394 μg cm[sup -2]) were obtained in which the protein A-immobilized poly(HEMA) membranes were used. Much higher amounts of human-IgG (up to 489 μg cm[sup -2]) were adsorbed from human plasma. Up to 91 % of the adsorbed human-IgG was desorbed by using 0.1 M aminoacetic acid as elution agent. The adsorption-desorption cycle was repeated ten times using the same polymeric membranes. There was no remarkable reduction in the adsorption capacity of the protein A-immobilized poly(HEMA) membranes. [ABSTRACT FROM AUTHOR]

The dichlorotriazinyl dye-ligand Procion Red HE-3B-anchored poly(EGDMA-HEMA) membranes were used for removal of heavy metal ions (i.e., copper, arsenic, cadmium and mercury) from aqueous media containing different amounts of these ions (0.1–4.5 mmol/L) and at different pH values (2.0–8.0). The HE-3B-anchored membranes from their single solutions were 6.4 mmol/m2 for Cu(II), 30.1 mmol/m2 for As(III), 76.3 mmol/m2 for Cd(II) and 130.3 mmol/m2 for Hg(II). When the heavy metal ions competed (in the case of the adsorption from their mixture) the adsorption capacities were 7.8 mmol/m2 for Cu(II), 24.5 mmol/m2 for As(III), 27.6 mmol/m2 for Cd(II) and 42.3 mmol/m2for Hg(II). The same affinity order was observed under non-competitive and competitive adsorption which was as follows: Hg(II) > Cd(II) > As(III) > Cu(II). The adsorption of heavy metal ions increased with increasing pH and reached a plateau value at around pH 5.0. Heavy metal ion adsorption from artificial wastewater was also studied. The adsorption capacities are 4.1 mmol/m2 for Cu(II), 12.5 mmol/m2 for As(III), 16.7 mmol/m2 for Cd(II) and 21.3 mmol/m2 for Hg(II). Desorption of heavy metal ions was achieved using 0.1 M HNO3. The Procion Red HE-3B-anchored membranes are suitable for repeated use for more than 5 cycles without noticeable loss of capacity. [ABSTRACT FROM AUTHOR]

Various changes in the environment can occur as drug delivery systems travel to the targeted area. Therefore, it is an important aspect to consider the effects of environmental changes such as pH and temperature on the release in the development of drug delivery systems. Microcryogels having predefined shape and size were fabricated as drug delivery systems and loaded with diclofenac sodium, a non-steroidal anti-inflammatory drug. Physicochemical, structural, and morphological properties of microcryogels were investigated by swelling, pore volume and porosity tests, infrared spectroscopy, and field emission scanning electron microscopy. Effects of medium pH on drug release were examined at release media with the pH 2.0 as simulated gastric juice, pH 7.4 as the simulated intestinal fluid/intravenous solution, pH 6.0 as a simulated medium during a normal wound healing, and pH 9.0 as a simulated medium for infected wounds. Effects of temperature on drug release were also analyzed at 37 °C as normal body temperature and 42 °C as inflammatory temperature. The obtained results showed that drug release was too low in acidic environment than those observed at higher pH values. Moreover, the release rates were higher at inflammatory temperature compared with the ones at normal body temperature. [Display omitted] • Microcryogels (MCs) having large pores were successfully fabricated. • Polyethylenimine was grafted on MCs for stimuli-responsive drug release. • MCs-PEI exhibited pH-sensitive swelling. • MCs-PEI delivery system shows pH/thermo-sensitive release behavior. [ABSTRACT FROM AUTHOR]

pHEMA membranes carrying 25.6 mmol Procion Blue MX-3G/m2 were used for removal of heavy metal ions (i.e., copper, arsenic, cadmium, and mercury) from aqueous media containing different amounts of these ions (0.1–4.5 mmol/L) and at different pH values (2.0–8.0). The maximum adsorption capacities of heavy metal ions onto Procion Blue MX-3G-attached membranes under noncompetitive conditions were 5.6 mmol/m2 for Cu(II), 19.6 mmol/m2 for As(III), 46.2 mmol/m2 for Cd(II), and 119.6 mmol/m2 for Hg(II). The competitive adsorption capacities of the heavy metal ions were 6.9 mmol/m2 for Cu(II), 21.2 mmol/m2 for As(III), 33.9 mmol/m2 for Cd(II), and 52.5 mmol/m2 for Hg(II). The same affinity order was observed under noncompetitive and competitive adsorption: Hg(II) > Cd(II) > As(III) > Cu(II). The adsorption of heavy metal ions increased with increasing pH and reached a plateau value at around pH 6.0. Adsorption of heavy metal ions from artificial wastewater was also studied. The adsorption capacities are 3.5 mmol/m2 for Cu(II), 10.2 mmol/m2 for As(III), 24.7 mmol/m2 for Cd(II), and 37.3 mmol/m2 for Hg(II). Desorption of heavy metal ions was performed using 0.1 M HNO3. Procion Blue MX-3G-attached membranes are suitable for repeated use of more than 5 cycles without noticeable loss of capacity. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: Chiral ligand-exchange enantioseparation of aliphatic and aromatic amino acids was successfully performed using a new open-tubular zwitterionic column with tentacle-type polymer stationary phase. The polymeric stationary phase was prepared using 3-chloro-2-hydroxypropyl methacrylate (HPMA-Cl), a new reactive monomer. The preparation procedure of the open-tubular column included silanization, in situ graft polymerization with HPMA-Cl, and l-histidine (l-His) modification. l-His was used as a chiral ligand-exchange selector and copper(II) as a central ion. Successful enantioseparation of six pairs of amino acid enantiomers was achieved with a buffer of 5mM CuSO4, 20mM (NH4)2SO4 at pH 3.0. [Copyright &y& Elsevier]

Nanotechnology is an important science that finds a wide range of applications from energy production to industrial production processes and biomedical applications. Nanoparti-cles, which are the most frequently preferred nanomaterials that form the basis of nanotechnolo-gy, are prepared with different composition, size, shape and surface chemistry to provide new techniques in applications in many different fields. The use of nanoparticles in the preparation of plasmonic sensors has increased the interest in plasmonic sensors such as surface plasmon resonance, electrochemical sensors, surface enhanced raman scattering and colorimetric sensors due to their increased sensing capacity on sensor surfaces. Plasmonic sensors are an important option in many different fields, such as medicine, environmental agriculture and food safety, thanks to their ability to solve a multitude of challenges. Because, plasmonic sensors are defined as sensing devices with important features such as sensitive and fast detection, no need for labels, real-time analysis, portability. In this review, the information about nanoparticles and their types and working principles of plasmonic sensors is given. Then, examples in clinical applications using different plasmonic sensors prepared with plasmonic nanoparticles are discussed in detail. [Display omitted] • This review focuses on different nanoparticle-based plasmonic sensors used for clinical applications. • The types, advantages and disadvantages of different plasmonic sensors used for diagnosis of diseases are described in clinical applications. • Different plasmonic sensor studies prepared in the literature for clinical applications are discussed and aimed to guide future research. [ABSTRACT FROM AUTHOR]

• Three SPR sensors were prepared for sensitive recognition of Cd(II) ions. • SPR sensor is stable and repeatable with 0.01 µg/mL limit of detection value. • Sensitive detection methods were developed for wastewater control. • Sensor is stable with rapid response time at room temperature. This study reports a sensitive sensor-based measurement technique for selective and sensitive detection of Cd(II) ions at low concentrations using ion-imprinted technology. Heavy metal pollution is an extremely hot topic on scientific research for several decades. Cd(II) is one of the most toxic and carcinogenic heavy metals. The limit of concentration of Cd(II) ions allowed to be found in the drinking water and industrial wastewater has been defined as 3 µg/L by the World Health Organization. Therefore, a simple, reliable and effective method is required for the determination of Cd(II) ions. Surface plasmon resonance sensor is the most commonly used optical sensors due to their unique ability for real-time monitoring the molecular binding events. We have proposed a sensitive experimental platform capable of achieving detection in 6–7 min. In this work, the benefits of three different approaches were compared according to their performance enhancement effects on sensors. Poly(hydroxyethyl methacrylate) thin-film, polymeric nanoparticles, and gold nanoparticles were separately used for designing sensors surface for the sensitive detection of Cd(II) ions. Combination of the signal enhancing properties of nanoparticles and ion-imprinting technique provided sensitive and selective detection with a comparatively low limit of detection value to the SPR sensor system. The limit of detection value has been defined as 0.01 µg/L for selective Cd(II) ions detection which is less than the value determined by the World Health Organization. The real time detection of Cd(II) ions from wastewater solutions (SPS Quality Control Material Waste Water Level 2) was also carried out by the SPR sensors. [ABSTRACT FROM AUTHOR]