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Intrauterine devices (IUDs) are widely used in preventing fertilization as contracepting devices. In market, they are produced as T-shaped polyethylene (or propylene) and metal (especially copper) composites. Although the metal component is utilized to provide antibacterial efficacy, prolonged implantation and the presence of a wide range of bacteria flora in the intrauterine environment make IUDs susceptible to bacterial contamination, biofilm formation, and unpleasant infection. In the presented study, the propolis, a natural anti-bacterial/-viral product used for different biomedical applications, coating strategy was applied comparatively in three different ways: coating directly on metal components, coating on polymeric material, and using carrying polymer. In addition, antibacterial activity against Gram-positive (Staphylococcus aureus, S. aureus) and Gram-negative (Escherichia coli, E. coli) bacterial strains were investigated by both dynamic bacterial culture (bacterial inhibition activity) and biofilm (biofilm formation resistance) tests. As a result of 48 h of dynamic bacterial culture; it was determined that the antibacterial inhibition efficiency depending on propolis concentration increased up to 99.5% and 98.5% for E. coli and S. aureus, respectively. In addition, the carrying polymer allows IUDs to cover surfaces more homogeneously, as well as improve antibacterial activity. Similarly; it was determined that biofilm formation resistance was improved by 44.33% for E. coli and by 45.99% for S. aureus with both the propolis concentration and the use of carrying polymer. As a result, it has been revealed that propolis will be classified as an alternative, promising, and effective coating agent for improving antibacterial properties and biofilm formation resistance of IUDs. [ABSTRACT FROM AUTHOR]

Sedentary lifestyle, malnutrition and intense work hours resulting in high stress are challenging the human mind and psychology. Many people are genetically predisposed, but many, unfortunately, are unable to withstand this life and need professional support. Although technology is produced to make life easier, in practice it causes many people to live outside the border. Antidepressants, which are used as a result of professional support, benefit in the short term, but they cause serious damage to environmental and aquatic life on the invisible side of the iceberg due to personal waste, irregular use and overdose. If there is no follow-up and environmental removal, all non-target creatures other than humans will be damaged in a very short time, and hence this damage will return to the human being, like a boomerang. Although many methods have been developed for the treatment of these types of pollutants today, it is clear that new agents and methods should be developed that will enable mobile study in natural environment where the pollution emerges. Accordingly, the aim of this review is to make a critical analysis of studies on the determination, removal, and elimination of antidepressants in recent years and to inspire future studies. [ABSTRACT FROM AUTHOR]

In this study, a new approach for the detection of benzo[a]pyrene (BaP) in aqueous media is presented by combining molecularly imprinted polymers (MIPs) with surface plasmon resonance (SPR) sensors. Herein, BaP imprinted sensor was fabricated on a SPR chip in the presence of a pre-polymerization complex of BaP and N-methacryloyl-L-phenylalanine, 2-hydroxyethyl methacrylate (HEMA), and ethylene glycol dimethacrylate (EGDMA). The developed sensor was characterized by atomic force microscopy, ellipsometry, and contact angle measurements. Association kinetics analysis via Scatchard, Langmuir, Freundlich, Langmuir–Freundlich isotherms were applied to the data and Langmuir adsorption model was found as the most accurate model for the affinity sensor system. MIPs-based SPR sensor linearly responded to BaP in a concentration range of 20-400 ng mL−1 with an excellent LOD of 14.97 ng L−1. The SPR sensor was found to be highly selective toward BaP according to the selectivity study results in the presence of interfering agents such as benzo[b]floranthene (BbF), benzo[k]floranthene (BkF), indeno[1,2,3-cd]pyrene (IcdP), and 1-naphthol. The studies demonstrated that MIPs-based SPR sensor provides rapid and reliable detection and identification of polyaromatic hydrocarbons (PAHs) within a quite short time. [ABSTRACT FROM AUTHOR]

In this study, a novel biopolymer based on poly(glycerol sebacic)-urethane (PGS-U) and its nanocomposites containing Cloisite@30B were synthesized by facile approach in which the crosslinking was created by aliphatic hexamethylene diisocyanate (HDI) at room temperature and 80 °C. Moreover, metronidazole and tetracycline drugs were selected as target drugs and loaded into PGSU based nanocomposites. A uniform and continuous microstructure with smooth surface is observed in the case of pristine PGS-U sample. The continuity of microstructure is observed in the case of all bionanocomposites. XRD result confirmed an intercalated morphology for PGSU containing 5 wt% of clay nanoparticles with a d-spacing 3.4 nm. The increment of nanoclay content up to 5%, the ultimate tensile stress and elastic modulus were obtained nearly 0.32 and 0.83 MPa, which the latter was more than eight-fold than that of pristine PGS-U. A sustained release for both dugs was observed by 200 h. The slowest and controlled drug release rate was determined in the case of PGSU containing 5 wt% clay and cured at 80 °C. A non-Fickian diffusion can be concluded in the case of tetracycline release via PGS-U/nanoclay bionanocomposites, while a Fickian process was detected in the case of metronidazole release by PGS-U/nanoclay bionanocomposites. As a result, the designed scaffold showed high flexibility, which makes it an appropriate option for utilization in the treatment of periodontal disease. [ABSTRACT FROM AUTHOR]

Polymethyl methacrylate (PMMA), called as bone cement, has been used in implant surgery, initially in dental practices, then in arthroplasty surgery for decades. Bone cement is a highly preferred chemical in the field of orthopedics due to its bone-like hardness and mechanical strength. Meanwhile, antibiotic-loaded cements are used in joints and similar surgeries are generally due to the risk of infection. In this study, we aimed to demonstrate the effects of borate mineral loading into bone cement on enhancing the antibacterial resistivity and cell integration as well as retaining mechanical properties. Moreover, the incorporation of minerals into bone cements makes them much more cost-friendly biomaterials for surgical operations. Herein, antibacterial properties were evaluated by using vancomycin- and gentamycin-susceptible strains of Enterococcus faecalis and Staphylococcus aureus whereas cell viability tests were performed by osteoblast cell lines. Three sets of the bone cements, plain, calcium borate-, and sodium borate-loaded, were prepared through commercial procedures and subjected to mechanical, antibacterial and cell viability tests. Percentage deformation determined by compression tests under 0.100 MPa pressure was determined in the range of 12.58%–10.67% in respect to the amount of sodium borate mineral loaded whereas that was determined in the range of 12.54%–9.87% in respect to the amount of calcium borate mineral loaded. Micro-CT results also supported good mineral integration and structural features of the composite bone cements. Furthermore, mineral incorporation enhanced the cell viability, in other words, cellular integrity, up to 101.28% for sodium borate-loaded (NB75, 7.5 g mineral) and 72.04% for calcium borate-loaded (CB75, 7.5 g mineral) bone cement according to the negative control group, fresh culture medium. As a conclusion, both of these minerals could be classified as promising alternatives for developing bone cements with better antibacterial resistivity and cellular integration properties. [ABSTRACT FROM AUTHOR]

Today, the surface imprinted polymers emerge in various fields as synthetic adsorbents gaining attention in a variety of application areas. In this study, Cu(II) ion surface imprinted poly(2-hydroxyethyl methacrylate-glycidyl methacrylate), poly(HEMA-GMA), cryogels were synthesized via modified two-step polymerization which is different from given in literature and the adsorption of Cu(II) ion from aqueous solution was investigated batch wise. In this respect, the method applied in this study is new in the literature despite heavy metal removal studies reported. The polyethyleneimine (PEI) molecule was used in polymeric structure as a ligand. The poly(HEMA-GMA) cryogels prepared was characterized via Fourier transform infrared spectroscopy (FTIR), inductively coupled plasma optical emission spectrometry (ICP-OES), elemental analysis, scanning electron microscopy (SEM) and the micro-computed tomography (μCT). [ABSTRACT FROM PUBLISHER]

Cryogels are used quite a lot nowadays for adsorption studies as synthetic adsorbents. In this study, lipase enzyme (obtained fromCandida cylindracea) adsorption capacity of poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-tryptophan), poly(HEMA-MATrp), and Cu(II) ions immobilized poly(HEMA-MATrp), poly(HEMA-MATrp)-Cu(II), cryogel membranes were synthesized to determine and compare the adsorption behavior of lipase enzyme. In this regard, the effect of pH, interaction time, lipase initial concentration, temperature and ionic strength on the adsorption capacity of these membranes was investigated. Maximum lipase enzyme adsorption capacities of poly(HEMA-MATrp) and poly(HEMA-MATrp)-Cu(II) cryogel membranes were determined as 166.4 mg/g and 196.4 mg/g, respectively. [ABSTRACT FROM AUTHOR]

For biomarker discovery, simultaneous removal of albumin and immunoglobulin G (IgG) become more important for both concentrating other species including potential biomarkers and getting rid of their masking effect. In this study, we have proposed a covalent and photosensitive cross-linking conjugation of the biomolecules on nanostructures for the depletion of target proteins from aqueous solution and serum. The effect of concentration, pH, temperature and ionic strength on the adsorption of twin affinity nanotraps based on Cibacron Blue F3GA and Protein A were investigated. The efficiency of albumin and IgG depletion from human serum was performed using sodium dodecylsulfate–polyacrylamide gel electrophoresis. [ABSTRACT FROM PUBLISHER]

In this study, a new molecular imprinting (MIP)-based monolithic cryogel column was prepared using chemically crosslinked molecularly imprinted nanoparticles, to achieve a simplified chromatographic separation (SPE) for a model compound, L-glutamic acid (L-Glu). Cryogelation through crosslinking of imprinted nanoparticles forms stable monolithic cryogel columns. This technique reduces the leakage of nanoparticles and increases the surface area, while protecting the structural features of the cryogel for stable and efficient recognition of the template molecule. A non-imprinted monolithic cryogel column (NIP) was also prepared, using non-imprinted nanoparticles produced without the addition of L-Glu during polymerization. The molecularly imprinted monolithic cryogel column (MIP) indicates apparent recognition selectivity and a good adsorption capacity compared to the NIP. Also, we have achieved a significant increase in the adsorption capacity, using the advantage of high surface area of the nanoparticles. [ABSTRACT FROM AUTHOR]

Magnetic poly(2-hydroxyethyl methacrylate-co-N-methacryloyl–L-phenyl alanine), p(HEMA-co-MAPA) nanoparticles were produced by emulsion polymerization technique. The nanoparticles were characterized by zetasizer, atomic force microscopy (AFM), transmission electron microscopy (TEM), electron spin resonance spectroscopy (ESR), and Fourier transformed infrared spectroscopy (FTIR) techniques. Experimental conditions were optimized for DNA adsorption in aqueous media. The effects of several factors (i.e., temperature, pH, equilibrium concentration of DNA, salt type, and ionic strength) on adsorption capacity were examined in batch studies. The maximum DNA adsorption capacity was 211.3 mg/g for nanoparticles consisting of magnetite. The adsorption isotherms and kinetics were also examined. The Langmuir model and pseudo second-order kinetics are the best fitted to the data. Following the ten adsorption-desorption cycles, the decrease in adsorption capacity was only 12%. Finally, plasmid DNA was purified fromE.colilysate by magnetite nanoparticles consisting of MAPA. The purity and molecular mass of purified plasmid DNA were determined by the use of agarose gel electrophoresis resulting in 7000 base pairs for molecular mass and OC pDNA form following elution. [ABSTRACT FROM AUTHOR]

In this study, monolithic high performance liquid chromatography (HPLC) composite columns were synthesized for immunoglobulin G (IgG) separation by boronate affinity chromatography. 4-Vinyl phenyl boronic acid (VPBA) was polymerized with 2-hydroxyethyl methacrylate (HEMA). The poly(HEMA-VPBA) monoliths were crushed into fine particles by using ball-milling. Then, the crushed particles were embedded into poly(2-hydroxyethyl methacrylate) (PHEMA) cryogels to prepare monolithic HPLC composite columns. The PHEMA cryogel was also synthesized to evaluate the efficiency of the embedding process. The monolithic HPLC composite columns were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), surface area measurements, boron content analysis, swelling studies, and flow rate-back pressure relation. The performance of IgG separation of monolithic composite columns was determined with HPLC and the parameters such as pH, IgG concentration, temperature, flow rate, and ionic strength were investigated. The maximum adsorption was observed at pH 8.0 phosphate buffer. The IgG separation from human plasma was also performed and selectivity experiments were carried out with human serum albumin (HSA) and hemoglobin (Hb) as competitors. [ABSTRACT FROM AUTHOR]

In this study, we focused our attention on preparing of a new adsorbent for specific separation of immunoglobulin G (IgG). In this respect, we applied core–shell surface imprinting approach. Silica microspheres were selected as core-material to prepare specific surface imprinted polymer against IgG. Silica surface was activated via acidic treatment and modified with 3-methacryloyloxypropyl trimethoxysilane (MPTMS). Then, IgG molecules were imprinted on the surface of microspheres by usingN-methacryloyl-L-aspartic acid as complexing/functional monomer. The core–shell silica microspheres were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, thermo gravimetric analysis and zeta size analysis. Then, the microspheres were used for the separation of IgG from aqueous solution to evaluate/optimize conditions. The effect of parameters such as concentration, pH, ionic strength, and temperature on the separation of IgG were evaluated in their relevant ranges. The maximum IgG adsorption capacities of IgG-imprinted and non-imprinted core–shell silica microspheres were found to be 15.43 and 9.43 mg/g, respectively, at pH 6.0 phosphate buffer. 1.0 M NaCl was used as a desorption agent. Selectivity of the imprinted microspheres was also investigated by using human serum albumin and haemoglobin as competitor molecules. [ABSTRACT FROM PUBLISHER]

The main problem in cancer chemotherapy is the cytotoxic side effects of therapeutics on healthy tissues and cells. The targeted drug delivery and nanotechnology are intensively investigated area to find new ways to solve, at least to reduce, these problems. Hereby, we have reported a new method inspired from both conventional military strategies and biorecognition in the body. In this respect, we have produced two fluorescent nano-drug systems with bitargeting and biorecognition properties, recognizing cancer cells and each other. The multiplexed nanostructures were interacted with HL-60 cells to show their efficiency for bitargeting, ambushing, timed, and double-controlled cancer cell apoptosis. [ABSTRACT FROM AUTHOR]

Magnetic separation technology is a quick and easy method for sensitive and reliable detection, separation, and purification of biomolecules from any medium. Dopamine plays a crucial role for human metabolism; hence the development of selective and robust interference free methods for dopamine (DA) detection is of great importance. In the present study, we have reported an alternative method for the detection of DA which overcomes interference by coexisting compounds. We have designed a magnetically stabilized fluidized bed system (MSFB) by using fluorescein isothiocyanate (FITC) conjugated magnetic graphene oxide sheets (magGOs) as preconcentrator and diagnostic tool. In the presence of coexisting molecules, ascorbic acid (AA) and uric acid (UA), FITC-magGOs showed selectivity to DA as 39- and 34-folds, respectively. Compared with DA, a negligible amount of AA and UA were captured by FITC- magGOs non-specifically. Maximum DA adsorption capacity of FITC-magGOs was found to be 46.21 mg/g. The characteristics of the DA adsorption behavior were described by the application of the Langmuir isotherm model with monolayer adsorption more accurately. All experiments were carried out in the neutral solutions at around physiological pH. [ABSTRACT FROM AUTHOR]

Poly(2-hydroxyethyl methacrylate)/3-(2-imidazoline-1-yl)propyl(triethoxysilane) (PHEMA/IMEO) nanoparticles were attached on surface plasmon resonance (SPR) sensor for the real-time detection of human immunoglobulin G (IgG) in human serum. The PHEMA/IMEO nanoparticles-attached SPR sensor was characterized by Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM), and contact angle measurements. IgG detection studies were performed using aqueous IgG solutions at different concentrations. In order to show the selectivity and specificity of the SPR sensor, competitive kinetic analyses were performed using IgG, albumin, hemoglobin in singular and competitive manner. Finally, IgG detection in human serum was carried out. [ABSTRACT FROM AUTHOR]

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

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). Cu2+ biosorption properties of magnetically modified yeast cells from synthetic solutions were utilized in a continuous magnetic system. The Cu2+ ion-binding capacity decreased drastically with the increase of the flow rate. The maximum Cu2+ biosorption capacity was obtained to be 1.2 mmol/g at 25°C. Biosorption of Cu2+ increased with increasing pH and then reached almost a plateau value around pH 4.0. The yeast biomass can be easily regenerated by 0.1 M HNO3 with higher effectiveness. Biosorption of heavy metal ions from artificial wastewater was also studied. The biosorption capacities are 0.92 mmol/g for Cu2+, 0.52 mmol/g for Hg2+, and 0.28 mmol/g for Ni2+. Magnetically-modified yeast cells exhibits the following metal ion-affinity sequence: Cu2+ > Hg2+ > Ni2+. [ABSTRACT FROM AUTHOR]

Concanavalin A (Con A) immobilized monosize and magnetic poly(glycidyl methacrylate)[m-poly(GMA)] beads were investigated for specific adsorption of yeast invertase from aqueous solutions. m-Poly(GMA) beads (1.6 μ m in diameter) were prepared by dispersion polymerization in the presence of Fe3O4 nanopowder. The epoxy groups of m-poly(GMA) beads were opened by base catalyses. Then, Con A was immobilized by covalent binding onto the beads. Con A immobilization amount was 12.5 mg/g. The invertase adsorption capacity of the m-poly(GMA)/Con A beads was 111 mg/g. The maximum invertase adsorption on the m-poly(GMA)/Con A beads was observed at pH 5.5. The optimum activity for both free and adsorbed invertase was observed at 50°C. Vmax values were determined as 330 U/mg and 292 U/mg enzyme, for free and adsorbed invertase, respectively. KM values were found to be the same for free and adsorbed invertase (20 mM). Adsorption of invertase via Con A improved the pH stability of invertase. Thermal stability also increased with adsorption. The adsorbed enzyme activity was found to be quite stable in repeated experiments. [ABSTRACT FROM AUTHOR]

The aim of this study is to prepare magnetic beads which can be used for the removal of heavy metal ions from synthetic solutions. Magnetic poly(ethylene glycol dimethacrylate-vinyl imidazole) [m-poly(EGDMA-VIM)] beads were produced by suspension polymerization in the presence of magnetite Fe3O4 nano-powder. The specific surface area of the m-poly(EGDMA-VIM) beads was found to be 63.1 m2/g with a size range of 150-200 µm in diameter and the swelling ratio was 85%. The average Fe3O4 content of the resulting m-poly(EGDMA-VIM) beads was 12.4%. The maximum binding capacities of the m-poly(EGDMA-VIM) beads were 32.4 mg/g for Cu2+, 45.8 mg/g for Zn2+, 84.2 mg/g for Cd2+and 134.5 mg/g for Pb2+. The affinity order on mass basis is Pb2+>Cd2+>Zn2+>Cu2+. Equilibrium data agreed well with the Langmuir model. pH significantly affected the binding capacity of the magnetic beads. Binding of heavy metal ions from synthetic wastewater was also studied. The binding capacities were 26.2 mg/g for Cu2+, 33.7 mg/g for Zn2+, 54.7 mg/g for Cd2+ and 108.4 mg/g for Pb2+. The magnetic beads could be regenerated up to about 97% by treating with 0.1 M HNO3. These features make m-poly(EGDMA-VIM) beads a potential candidate for support of heavy metal removal under magnetic field. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis is characterized by chronic polyarthritis and destruction of multiple joints. In this study, poly(hydroxyethyl methacrylate-N-methacryloyl-(L-histidine)-methylester) (PHEMAH) beads were used in the removal of pathogenic antibodies from rheumatoid arthritis patient plasma in a packed bed column. PHEMAH beads, in the size range of 80–120 μm, were produced by suspension polymerization. The beads were contacted with blood in an in vitro system. Loss of blood cells and clotting times were followed. PHEMAH beads were characterized by scanning electron microscopy. We found that PHEMAH beads had a spherical shape and porous structure. Loss of cells in the blood contacting with PHEMAH beads was negligible. IgM-antibody adsorption capacity decreased significantly with the increase of the plasma flow-rate. With increasing IgM-antibody concentration, the amount of IgM-antibody adsorbed per unit mass increased and then reached saturation. Maximum IgM-antibody adsorption amount was 69.2 mg/g. IgM-antibody molecules could be repeatedly adsorbed and desorbed without noticeable loss in the IgM-antibody adsorption amount. [ABSTRACT FROM AUTHOR]

A method based on histidine ligand affinity chromatography has been utilized for the separation of DNA hydrolyzing autoantibodies from sera of patients suffering from systemic lupus erythematosus and primary antiphospholipid syndrome using the gel, histidyl-aminohexyl-sepharose. The separation of autoantibodies was carried out under mild chromatographic conditions. Human IgG subclass distribution in the different fractions separated on the column was studied by enzyme-linked immunosorbent assay. The purified DNA hydrolyzing autoantibodies were shown to hydrolyze plasmid DNA. [ABSTRACT FROM AUTHOR]

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]

Molecular recognition based separation systems have received much attention because of their high selectivity for target molecules. Molecular imprinting has been recognized as a promising technique for the development of affinity adsorbents. Molecularly imprinted polymers (MIP) are easy to prepare, stable, inexpensive, and capable of molecular recognition. Cadmium is a carcinogenic and mutagenic element. The limit value of cadmium in blood should be no higher than 50 pg/L when exposure to cadmium is unavoidable in industry. There is no specific treatment available for acute or chronic metal poisoning. Besides supportive therapy and hemodialysis, metal poisoning is often treated with commercially available chelating agents including EDTA and dimercaprol. However, there is histopathological evidence for increased toxicity in animals when these agents are utilized. The aim of this study is to prepare superporous ion-imprinted polymer monolith which can be used for the selective removal of Cd2+ ions from Cd2+ -overdosed human plasma. N-methacryloly-(L)-cysteinemethylester (MAC) was chosen as the complexing monomer. In the first step, MAC synthesized by using methacryloyl chloride and cysteine. Cd2+ was complexed with MAC monomer and the Cd2+-imprinted poly(HEMA-MAC) monoliths were synthesized by bulk polymerization. After that, Cd 2+ ions were removed by 0.1 M thiourea and 0.1 M HNO3 solutions, respectively. Cd2+-imprinted poly(HEMA-MAC) monoliths had a specific surface area of 226.8 m²/g and the swelling ratio was determined to be 76%. According to the elemental analysis results, monoliths contain approximately 58.3 μmol/g of MAC. The maximum adsorption capacity for Cd2+ ions was 26.6 μmol/g of the dry weight of monolith. The adsorption capacity decreased significantly from 23.25 μmol/g to 3.08 μmol/g polymer with the increase of the flow-rate from 1 mL/min to 4 mL/min. The Cd2+-imprinted poly(HEMA-MAC) monolith could be used many times without decreasing their adsorption capacities significantly. [ABSTRACT FROM AUTHOR]

In this study, human serum albumin (HSA) adsorption properties of reactive green HE-4BD-attached monodisperse poly(styrene-2-hydroxyethyl methacrylate) [poly(St-HEMA)] microspheres were investigated. Poly(St-HEMA) microspheres with an uniform size of 4.0 µm in diameter were produced by the dispersion copolymerization of St and HEMA in an ethanol–water medium. Reactive green HE-4BD was covalently attached onto the poly(St-HEMA) microspheres via a nucleophilic substitution reaction between the hydroxyl groups of HEMA and triazinyl chloro groups of dye with the equilibrium coupling capacity of 45.8 µmol dye (g polymer)−1. The poly(St-HEMA) monodisperse microspheres were characterized by scanning electron microscopy. The effect of concentration of HSA, medium pH, and ionic strength on the adsorption efficiency of dye-attached microspheres were studied in a batch system. The nonspecific adsorption of HSA on the poly(St-HEMA) microspheres was 2.1 mg g−1. Reactive green HE-4BD attachment significantly increased the HSA adsorption up to 221 mg g−1. The langmuir adsorption model was found to be applicable in interpreting HSA adsorption by reactive green HE-4BD attached microspheres. Significant amount of the adsorbed HSA (up to 92%) was eluted in 1 hr in the elution medium containing 1.0-M NaCl. To determine the effects of adsorption conditions on possible conformational changes of HSA structure, fluorescence spectrophotometry was employed. We resulted that poly(St-HEMA) dye-affinity microspheres can be applied for HSA adsorption without causing any significant conformational changes. Repeated adsorption/elution processes showed that these dye-attached monodisperse microspheres are suitable for HSA adsorption. [ABSTRACT FROM AUTHOR]