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High cholesterol grades are a significant threat factor for coronary heart disease, which leads to heart attacks. General practices focus on lowering cholesterol and saturated fatty acids in the diet to decrease the incidence of cardiovascular diseases. Milk is a primary food with high nutritional value and high consumption. Molecularly imprinted cryogels are an excellent alternative according to non-selective methods such as liquid–liquid and/or solid-phase extraction to elute cholesterol selectively from milk. Because the cryogels are low cost, they can be synthesized easily, and the sample can be applied directly to the cryogel without needing any pre-treatment. In this study, we synthesized cholesterol-imprinted (Chl-MIP) cryogel membranes employing aminoacid-based hydrophobic functional comonomer N-methacryloyl-L-phenylalanine to be used as a selective adsorbent to remove cholesterol from milk samples. Chl-MIP cryogel exhibited a maximum Chl adsorption capacity of 12.01 mg/g at 25 °C with an interaction time of 60 min. The selectivity of the cryogel was 2.89 times greater for estradiol molecules and 4.99 times greater for progesterone molecules. Chl-MIP cryogel provides a rapid mass transfer by a short diffusion path without any diffusion restrictions. This process is simple to implement, efficient, affordable, and feasible for use on modern manufacturing lines.

This study focuses on optical-based surface plasmon resonance (SPR) biosensors developed for the detection of allergen-specific serum immunoglobulin E (IgE). The SPR gold chip surface was functionalized with 3-mercaptopropionic acid (3-MPA) and then covalently bon- ded using N-ethyl-N’-(3-diethylaminopropyl) carbodiimide (EDC)/N-hydroxysulfosuccinimide (NHS) to activate the carboxylic acid. Antibodies containing anti-immunoglobulin E (anti-IgE) were then immobilized on the chip surface with terminal amine groups as biotransport sites. The modified SPR chip surface was realized the characterization studies by atomic force microscopy (AFM), contact angle measurements, and ellipsometry. Three different contact angle values were determined, emphasizing the hydrophilicity of the surface: unmodified gold surface 60.5°, 3-MPA modified surface 28.13°, and EDC-NHS/anti-IgE modified surface 36.38°. The morphological analysis using AFM revealed that the unmodified SPR chip surface had a depth of 0.28 nm, while the EDC-NHS/anti-IgE modified SPR biosensor chip surface had a depth of 8.36 nm. The experiments conducted for IgE detection exhibited high selectivity within the range of 1.0–1000 ng/mL. Selectivity studies were performed with bovine serum albumin, immunoglobulin G (IgG), and myoglobin as similar proteins. The limit of detection and quantification values were obtained as 0.051 and 0.153 ng/mL, respectively. This study highlights the potential of SPR biosensors to provide high sensitivity and specificity for detecting allergen-specific IgE, indicating promising future applications in allergy diagnosis. The results underscore the importance of highly sensitive detection of allergen-specific IgE in accurately diagnosing and effectively treating allergic diseases.

The aim of the present study is to develop a surface plasmon resonance sensor for the detection of vitamin B2, vitamin B9, and vitamin B12 in food samples by using the molecular imprinting technique. The vitamin B2, vitamin B9, and vitamin B12 imprinted and the non-imprinted surface plasmon resonance sensor chip surfaces were characterized by using contact angle measurements, atomic force microscopy, ellipsometry, and Fourier transform infrared-attenuated total reflectance. The real-time detection of vitamin B2, vitamin B9, and vitamin B12 was analyzed by using aqueous solutions in the concentration range of 0.01 ng/mL − 10 ng/mL for vitamin B2, 0.1 ng/mL − 8.0 ng/mL for vitamin B9, and 0.01 ng/mL − 1.5 ng/mL for vitamin B12. The limit of detection values was calculated as 1.6×10−4ng/mL for vitamin B2, 13.5×10−4ng/mL for vitamin B9, and 2.5×10−4ng/mL for vitamin B12, respectively. Selectivity experiments were performed by using vitamin B1 and vitamin B6. The reproducibility of surface plasmon resonance sensors was investigated both on the same day and on different days for four times. Validation studies of the prepared surface plasmon resonance (SPR) sensors were performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS).

Molecular imprinting is a technique that enables the generation of customized binding sites for specific molecules. Molecularly imprinted polymers are versatile materials distinguished by their ease of synthesis, exceptional stability even under harsh conditions, prolonged lifespan, and the establishment of predetermined selective cavities through the polymerization process. The molecular imprinting technique, often preferred in purification and separation studies due to its superior properties, has also been utilized in medical applications in recent years. It frequently emerges, particularly in the diagnosis of cancer and microbial diseases. High accuracy percentage and the number of reuses, along with low cost, are among the preferred reasons for its use in diagnoses. Additionally, the rapid response of molecularly imprinted biomaterials shortens the duration of diagnoses. Furthermore, tissue engineering has also focused on exploring the potential of creating bioactive scaffolds with superior recognition properties as molecularly imprinted biomaterials in recent years. In the pharmaceutical sector, molecularly imprinted biomaterials are also utilized for their superior recognition and separation properties. There is considerable research on the use of molecularly imprinted polymers in the separation of chiral enantiomers, for example. Compared to traditional methods, their lower cost and specificity contribute to the increased utilization of these biomaterials. This review aims to showcase the rapidly increasing utilization and advancements of biomaterials prepared using molecular imprinting techniques in recent years in the pharmaceutical field, particularly in the diagnosis of cancer and microbial diseases, as well as in regenerative medicine.

In recent years, injectable cryogels have been frequently used in various biomedical applications such as tissue engineering, drug delivery, therapeutics, therapy, cell transplantation and immunotherapy. Cryogels, one of the biomaterials with injectable 3D scaffold structures, have important properties such as biocompatibility, physical resistance, macropore and sensitivity. In addition to being biocompatible, cryogels, consisting of three-dimensional (3D) scaffolds with physicochemical properties such as elasticity, hardness and biological degradation, provide a structural support environment for tissue development along with cell attachment. In addition, injectable cryogels can be loaded with therapeutic agents or cells in tissue engineering and clinical studies. The purpose of this review is to explain the physical and chemical properties of injectable cryogels consisting of three-dimensional scaffolding, after explaining the properties and synthesis stages of cryogels, and it is thought to be a guide to make their use in different areas more widespread for future studies.

Darunavir (DRV) is a crucial antiretroviral drug specifically developed for treating infections that require prolonged treatment. It has gained significant recognition as one of the top choices for combating AIDS, a condition caused by the human immunodeficiency virus. Biopolymeric materials like microcryogels become the center of attention in most research areas such as controlled release systems. These systems offer the advantage of precise drug administration, ensuring effective therapeutic outcomes through the delivery of specific drug doses. Microcryogels, characterized by their super macroporous, elastic, and spongy morphology, have emerged as a focal point in biomedical applications, particularly when combined with molecularly imprinted polymers. In this study, the controlled release and kinetics studies of the DRV were investigated with the DRV-imprinted poly(2-hydroxyethyl methacrylate) (pHEMA)-based microcryogels. Darunavir imprinted pHEMA microcryogels with different cross-linker ratios and different loaded drugs were prepared for studies of in vitro release of DRV; scanning electron microscopy, Brunauer–Emmett–Teller, and Fourier transform infrared spectroscopy methods have been considered suitable for the characterization of cryogels that have been designed and whose sensitivity has been enhanced by molecular imprinting. Cytotoxicity of DRV-imprinted microcryogels was also inspected using mouse fibroblast cell line L929. The comprehensive analysis results underscore the potential of these meticulously designed microcryogels, showcasing their utility in medical applications. Notably, these microcryogels exhibited controlled drug release, with efficiency levels of up to 85% and sustained release duration of 40 h, positioning them as a valuable option for advanced drug delivery systems in the medical field.

Cryogel, a porous polymer material that is frequently used in recent years, has been evaluated in conjunction with alternative treatment methods. Natural polymers are well known for their high biocompatibility, and as a result, there are many studies that focus on the relationship between structure and function in plant-based biopolymers. To this end, various dressing materials, including gelatin, alginate, chitosan, and inorganic materials, have been developed as biopolymers. In this study, gelatin-based cryogels containing three different concentrations of Melaleuca alternifolia(tea tree plant) oil (TTO-GCry) were synthesized under specified conditions, and characterization studies were carried out. Their antibacterial activity was evaluated using two bacterial strains (E. coliand S. aureus). The results showed that the antibacterial effectiveness of the developed cryogels on E. coliwas between 21–50%, and on S. aureuswas between 28–72%. Furthermore, viability analysis using human keratinocyte cell lines (HaCaT) showed no toxic effects. The cryogel exhibited biocompatibility, indicating promise for use in skin injury and wound healing applications. This environmentally friendly cryogel, with a macroporous structure and composed of natural materials, holds potential for diverse functions, bringing novelty to the literature.

In clinical applications, surface plasmon resonance sensors are widely used with many advantages including rapid and simultaneous response, high selective, sensitivity and specificity, portable and outstanding detection performance. Recently, the innovations and efforts in the field of sensor have expanded rapidly and have a wide range of applications, especially in the fields of environmental, medical, and pharmaceutical applications, and food safety. In particular, sensor systems were prepared with molecularly imprinted polymers create selective and specific recognition spaces for template molecules in a polymeric matrix, resulting in an important formation with surface modification techniques. In addition, this method provides a wide scope for imprinting various biomolecules with different three-dimensional structures and physical and chemical properties. Unlike time-consuming and complex surface modification methods, molecular imprinting technology offers sensitive, selective, fast, easy preparation, and use approaches especially for diagnostic, and theranostic applications. In addition, molecularly imprinted polymer-based sensors, with their low cost, reusability, high stability, physical and chemical robustness, have become very attractive methods for clinical applications with their sensitivity to very small structural changes in the structure of biomolecules. This review aims to summarize the molecular imprinting technology, the working principle of surface plasmon resonance (SPR) sensors, SPR sensor studies prepared with molecularly imprinted polymers in the literature and the future outlook of these concepts.

Molecularly imprinted polymers inspired by antigen-antibody interactions have received substantial interest as a biomimetic artificial receptor system in environmental applications. Herein, we present a molecularly imprinted surface plasmon resonance sensor integrated with gold nanoparticles for the identification of bisphenol A (BPA), an endocrine-disrupting chemical. We synthesized BPA-imprinted nanofilm consisting of amino acid-based functional monomers to selectively detect BPA from synthetic wastewater samples. BPA-spiked synthetic wastewater samples were analyzed to ensure the method's reliability and feasibility. Under ideal conditions, the suggested approach performed well in terms of analytical performance to bisphenol A, with a wide linear range of 0.1 to 10 µg/L and LOD of 10 ng/L. The sensor results align well with the Langmuir adsorption model. It has also been shown that repeated use of the sensor can be achieved. According to selectivity studies, bisphenol A adsorbed within the imprinted cavities favorably compared to 4-nitrophenol and phenol. The produced bisphenol A-imprinted surface plasmon resonance sensor provides improved sensitivity based on the signal amplification strategy, unconjugated sensing without the need for labelling, real-time sensing, low sample consumption rates, quantifiable assessment, and outstanding kinetic rate constant calculation in actual samples. Also, because the produced sensor is reusable with relative standard deviations (RSD)<1.25, indicating the sensor's precision, the surface plasmon resonance-based biomimetic BPA sensor is simple to practice and a cost-effective option.

In this study, Concanavalin A (Con A) imprinted surface plasmon resonance (SPR) biosensor was prepared for the determination of Con A. Con A imprinted SPR biosensors were characterized by atomic force microscopy, ellipsometer, and contact angle measurements. The kinetic studies were performed with pH scanning. For this purpose, Con A solutions were prepared with different pH buffers and were used for the detection of Con A. The kinetic analysis of the SPR biosensor was with Con A solutions ranging from 0.01 to 50 ng/mL. The limit of detection and limit of quantification were calculated at 0.0011 and 0.0038 ng/mL, respectively. Selectivity studies were conducted using SPR biosensors that were either Con A imprinted or non-imprinted, as well as competing molecules such as bovine serum albumin and myoglobin, which have a similar molecular structure. In order to determine Con A in clinical studies, kinetic analyzes were performed with Con A solutions prepared in artificial plasma and Jack bean solutions. The recovery of Con A was calculated using the obtained sensorgram data. Four consecutive analyses were performed on the same day to test the Con A molecule’s reusability. In order to test the reusability of the biosensor at various points in time, kinetic analyses were also performed during the first, second, fourth, and sixth months.

AbstractThis paper presents a modified QuEChERS method to determine 346 pesticide residues in honey by LC/MS-MS and GC/MS-MS. Acetate buffered acetonitrile extraction followed by dispersive SPE clean-up with C18-E, PSA and MgSO4sorbents were used for sample preparation. This method was validated according to the European Union SANTE/2019/12682 guidelines. Acceptable values were obtained for the linearity, the limit of detection (0.001–0.003 mg/kg), limit of quantification (0.002–0.008 mg/kg), trueness (for the four tested levels, the recovery assays values were between 76 and 112%), precision (RSD ≤20.0%) and measurement uncertainty tests (<50%). The method was used for the analysis of 100 honey samples from Northern Cyprus and residues of 4 pesticides (coumaphos, thiamethoxam, N-(2,4-dimethylphenyl)formamide, piperonyl butoxide) were quantified in 42 honey samples. Coumaphos (29%) and N-(2,4-dimethylphenyl)formamide (11%) were the residues frequently detected in the samples. N-(2,4-dimethylphenyl)formamide concentrations (0.56 and 0.84 mg/kg) were determined above the MRL limits (0.2 mg/kg) in two samples. This study shows that LC/MS-MS and GC/MS-MS in combination with modified QuEChERS can be used to routinely scan pesticide residues in honey samples and direct contamination with acaricides/veterinary drugs applied in the treatment of plagues in the hive during honey harvest is the main source of honey pollution in Northern Cyprus.

In this study, the patulin imprinted and the non-imprinted nanoparticles are synthesized by the two-phase mini emulsion polymerization method and characterized by zeta-size analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. Afterwards, the patulin imprinted and the non-imprinted nanoparticles are attached on the surface of surface plasmon resonance (SPR) chips. The patulin imprinted and the non-imprinted SPR nanosensors are characterized by using atomic force microscope, ellipsometer, and contact angle measurements. Kinetic studies for patulin detection are carried out in the concentration range of 0.5 nmolar–750 nmolar. The limit of detection and the limit of quantification values are obtained as 0.011 nmolar and 0.036 nmolar, respectively. In all kinetic analysis, the response time is 13 min for equilibration, adsorption, and desorption cycles. The selectivity studies of the patulin imprinted and the non-imprinted SPR nanosensors are determined in the presence of ochratoxin A and aflatoxin B1. In order to demonstrate the applicability, validation studies of the patulin imprinted SPR nanosensor are performed by liquid chromatography-tandem mass spectrometry (LC-MS).

Polymerizable terbium(III) complex-based fluorescent molecular imprinted smart nanoparticles were synthesized for the quantitative determination of potential metabolic destitution biomarkers. Melatonin has been reported to be one of the key factors in seasonal affective disorder (SAD) and was chosen as a model metabolite to demonstrate a novel molecularly imprinted polymer (MIP) nanoparticle sensor. We exploited lanthanide ion complexes in our biosensing platforms due to their deeper penetration ability, negligible autofluorescence, lack of photobleaching and photoblinking, and their sharp absorption and emission bands, extreme photostability, and long lifetime. Given the high affinity of lanthanide ions for carboxylic acid groups, we used two amino acid-based functional monomers, N-methacryloyl-l-tryptophan and N-methacryloyl-l-aspartic acid, to coordinate terbium(III) ions and melatonin, respectively. The fluorescent MIP nanoparticles were synthesized using a miniemulsion polymerization technique after forming complexes between terbium(III):MA-Asp and melatonin:MATrp molecules. Due to the polymerizability of lanthanide complexes, they were readily inserted into the polymeric chain, which enabled homogeneous distribution as well as closer orientation to the imprinted cavities for selective melatonin recognition.

Introduction: A molecular imprinting is one of the fascinating modification methods that employ molecules as targets to create geometric cavities for recognition of targets in the polymeric matrix. This method provides a broad versatility to imprint target molecules with different size, three-dimensional structure and physicochemical features. In contrast to the complex and timeconsuming laboratory surface modification procedures, this method offers a rapid, sensitive, inexpensive, easy-to-use, and selective approach for the diagnosis, screening and monitoring disorders. Owing to their unique features such as high selectivity, physical and chemical robustness, high stability, low-cost and reusability of this method, molecularly imprinted polymers have become very attractive materials and been applied in various applications from separation to detection. Background: The aims of this review are structured according to the fundamentals of molecularly imprinted polymers involving essential elements, preparation procedures and also the analytical applications platforms. Finally, the future perspectives to increase the development of molecularly imprinted platforms. Methods: A molecular imprinting is one of the commonly used modification methods that apply target as a recognition element itself and provide a wide range of versatility to replica other targets with a different structure, size, and physicochemical features. A rapid, easy, cheap and specific recognition approach has become one of the investigation areas on, especially biochemistry, biomedicine and biotechnology. In recent years, several technologies of molecular imprinting method have gained prompt development according to continuous use and improvement of traditional polymerization techniques. Results: The molecularly imprinted polymers with excellent performances have been prepared and also more exciting and universal applications have been recognized. In contrast to the conventional methods, the imprinted systems have superior advantages including high stability, relative ease and low cost of preparation, resistance to elevated temperature, and pressure and potential application to various target molecules. In view of these considerations, molecularly imprinted systems have found application in various fields of analytical chemistry including separation, purification, detection and spectrophotometric systems. Conclusion: Recent analytical methods are reported to develop the binding kinetics of imprinted systems by using the development of other technologies. The combined platforms are among the most encouraging systems to detect and recognize several molecules. The diversity of molecular imprinting methods was overviewed for different analytical application platforms. There is still a requirement of more knowledge on the molecular features of these polymers. A next step would further be the optimization of different systems with more homogeneous and easily reachable recognition sites to reduce the laborious in the accessibility in the three-dimensional polymeric materials in sufficient recognition features and also better selectivity and sensitivity for a wide range of molecules.

Molecularly imprinted polymers (MIPs) are cheap and easily prepared polymers that have specific recognition sites for the target molecule that suitable for recognition. MIPs are also synthetic materials designed to mimic the recognition properties of natural antibodies or receptors. The development of MIPs in optic sensors has introduced a significant novelty in the field of sensing technology. When integrated into optic sensors, MIPs offer several advantages and novel capabilities including selective recognition, versatility, stability and reusability, signal amplification, and tailored sensor design. Microfluidic systems are enable the control and movement of fluids in small volumes within micro-scale channels. MIPs, optic sensors and microfluidic systems have important superior features such as sensitivity, selectivity and low sample requirement. They are used together in the creation of fast, automated and self-contained systems. The combination of advantages makes microfluidic-based MIPs-integrated optic sensors a promising technology for various applications in analytical sciences, biomedical research, and environmental monitoring.

Amaranth imprinted nanoparticles were prepared by two-phase mini emulsion polymerization of hydroxyethyl methacrylate and ethylene glycol dimethacrylate using acrylamide and methacrylic acid as functional monomers. The amaranth non-imprinted nanoparticle was prepared with the same procedure without using amaranth. Amaranth imprinted and non-imprinted nanoparticles were attached on the chip surface modified with allyl mercaptan. The surfaces of the surface plasmon resonance (SPR) sensor were characterized by the ellipsometry, contact angle, and atomic force microscopy. Amaranth solutions with different concentrations (0.1mg/mL–150mg/mL) were prepared with the pH 7.4 phosphate buffer. The limit of detection and limit of quantification were 0.0180mg/mL and 0.06mg/mL, respectively. When the selectivity of the amaranth imprinted SPR sensor was compared with the competing molecules tartrazine and allura red, it was observed that the target molecule amaranth was 5.64 times and 5.18 times more selective than allura red and tartrazine, respectively. The liquid chromatography-mass spectrometry technique (LC-MS) was used for validation studies. According to the results obtained from both SPR sensor and LC-MS analyses, the amaranth recovery (%) from fruit juices was observed between 96% and 99%.

•Nano-scale separation techniques (NSTs) are key tools in sensitive bioanalytical methods.•Recent overview in NSTs is presented.•Recent and selected applications of molecular separation-analyses by means of NSTs are reviewed.•Nano-column technology is presented and discussed.•The most recent achievements based on NSTs are discussed.

A quartz crystal microbalance (QCM) biosensor was developed to detect highly metastatic breast cancer cells by functionalizing the gold sensor surface with transferrin attachment. MDA-MB 231 breast cancer cells with high and MCF 7 cells with low metastatic potential and transferrin expression were used. Serum starved MDA-MB-231 cells were used as control cells. First, poly(2-hydroxyethyl methacrylate) (PHEMA) nanoparticles were prepared by mini-emulsion polymerization of hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA). Nanoparticles were characterized with a zeta-sizer and then their suspension is dropped on the surface of the QCM and the dried QCM surface was modified further by activation with carbodiimide and transferrin attachment. The QCM biosensor was analyzed by using atomic force microscopy (AFM), ellipsometry, Fourier transform infrared spectrophotometry (FTIR) and contact angle measurements. The cells were applied to the derivatized QCM sensor to investigate the affinity and binding kinetics. The nanoparticles and transferrin were found to form a monolayer on the QCM surface. Binding kinetics were best fitted to the Langmuir–Freundlich adsorption model. The QCM signal was correlated well with the number of transferrin receptors on cells. It is concluded that the QCM biosensor functioning viatransferrin receptor interactions may be used to detect breast cancer cells with high metastatic potential.

The use of molecular imprinted polymers (MIPs), which provides a means for preparing stationary phases with predetermined selectivity for a target molecule in capillary electrochromatography (CEC), is attractive because it combines selectivity, higher separation efficiency and shorter analysis time. A bisphenol A (BPA)-imprinted monolithic capillary BPA/PMAPA column was synthesized for the selective separation of bisphenol A (BPA) from aqueous solutions containing the competitor molecule phenol (PH), which is similar in size and shape to the template molecule. BPA-imprinted monolithic column was prepared in the presence of the template molecule, BPA, which results in the formation of recognition cavities complementary to the template molecule, after the removal of template molecule. An amino acid based monomer, N-methacryloyl-l-phenyl alanine (MAPA), was used as the functional monomer. The new stationary phase contains both charged and hydrophobic groups originating from MAPA monomer, which behaves as both an electroosmotic flow (EOF) supplier and a hydrophobic matrix. The MAPA containing BPA imprinted column behaves as a mixed mode stationary phase, as ion exchanger and hydrophobic matrix depending on the pH of the medium. Scanning electron microscopy was used to identify the structural features of the molecular imprinted column. MIP column performance was evaluated by the electrochromatographic separation of alkylbenzenes. The novelty of this work originated from dual separation mechanism shown by MAPA, which has the ability to form both hydrophobic and electrostatic interactions by the charged and hydrophobic groups of phenylalanine amino acid. This new column with mixed-mode characteristics was then used successfully as the stationary phase in CEC for the selective separation of BPA in MIP systems.

Bisphenol A (BPA) imprinted poly(ethylene glycol dimethacrylate-N-methacryloyl-l-phenylalanine-vinyl imidazole) [poly(EGDMA-MAPA-VI)] film deposition on a SPR sensor with improved efficiency is described in this paper. The molecularly imprinted SPR sensor was characterized by FTIR-ATR, atomic force microscopy and ellipsometry. A water-compatible molecularly imprinted film has been developed for rapid, sensitive, and label-free detection of BPA in aqueous solutions prepared in Milli Q water, tap water and synthetic wastewater. The real-time response allows the detection of BPA with concentrations ranging from 0.08 to 10 μg L−1with LOD and LOQ values of 0.02 and 0.08 μg L−1in Milli Q water, 0.06 and 0.2 μg L−1in tap water and 0.08 and 0.3 μg L−1in synthetic wastewater, respectively. A significant increase in sensitivity was therefore expected due to the use of the imprinted poly(EGDMA-MAPA-VI) thin film. The method showed good recoveries and precision for the samples spiked with BPA. The results suggest that the imprinted SPR sensing method can be used as a promising alternative for the detection of BPA. The sensor data fitted well with the Langmuir adsorption model. The selectivity studies showed that the imprinted cavities formed in the polymeric nanofilm recognize BPA preferentially rather than 4-nitrophenol, hydroquinone, phenol and 8-hydroxy quinoline with a relative selectivity coefficient of 2.5, 2.6, 2.7 and 2.5, respectively. The prepared BPA imprinted SPR sensor enables high sensitivity, label-free detection, real-time monitoring, low volume sample consumption, quantitative evaluation, and determination of kinetic rate constants very well. In addition, the SPR based BPA sensor is easy to use and can be a cost effective solution due to the reusability of the prepared sensor. Furthermore, the storage stability will be higher than antibody-based detection methods.

A facile colorimetric sensor array for detection of multiple toxic heavy metal ions (Hg2+, Cd2+, Fe3+, Pb2+, Al3+, Cu2+, and Cr3+) in water is demonstrated using 11-mercaptoundecanoic acid (MUA)-capped gold nanoparticles (AuNPs) and five amino acids (lysine, cysteine, histidine, tyrosine, and arginine). The presence of amino acids (which have functional groups that can form complexes with metal ions and MUA) regulates the aggregation of MUA-capped particles; it can either enhance or diminish the particle aggregation. The combinatorial colorimetric response of all channels of the sensor array (i.e., color change in each of AuNP and amino acid couples) enables naked-eye discrimination of all of the metal ions tested in this study with excellent selectivity.

Abstract: The aim of this study is to prepare two different hydrophobic polymeric nanospheres for cholesterol removal. Poly(HEMA–MAT) nanospheres with an average size of 100nm and poly(HEMA–MAP) nanospheres with an average size of 158nm were produced by surfactant free emulsion polymerization of HEMA and MAT and MAP monomers. These hydrophobic nanospheres were characterized by FTIR, SEM, elemental analysis, particle size and surface area measurements. Cholesterol removal experiments were performed in a batch experimental set-up and removal medium was methanol. Cholesterol adsorption capacity of poly(HEMA–MAP) nanospheres was approximately three times higher than that of poly(HEMA–MAT) nanospheres. [Copyright &y& Elsevier]

Cibacron Blue F3GA was immobilized on poly(hydroxyethyl methacrylate) cryogel and it was used for selective and efficient depletion of albumin from human serum. The poly(hydroxyethyl methacrylate) was selected as the basic component because of its inertness, mechanical strength, chemical and biological stability, and biocompatibility. Cibacron Blue F3GA was covalently attached to the poly(hydroxyethyl methacrylate) cryogel to produce poly(hydroxyethyl methacrylate)‐Cibacron Blue F3GA cryogel affinity column. The poly(hydroxyethyl methacrylate)‐Cibacron Blue F3GA cryogel was characterized with respect to gelation yield, swelling degree, total volume of macropores, Fourier Transform Infrared spectroscopy, and scanning electron microscopy. It was found that the maximum amount of adsorption (343 mg/g of dry cryogel) obtained from experimental results is very close to the calculated Langmuir adsorption capacity (345 mg/g of dry cryogel). The maximum adsorption capacity for poly(hydroxyethyl methacrylate)‐Cibacron Blue F3GA cryogel column was obtained as 950 mg/g of dry cryogel for nondiluted serum. The adsorption capacity decreased with increasing dilution ratios while the depletion ratio of albumin remained as 77% in serum sample. Finally, the poly(hydroxyethyl methacrylate)‐Cibacron Blue F3GA cryogel was optimized for using in the fast protein liquid chromatography system for rapid removal of the high abundant proteins from the human serum.

Polymethacrylate‐based monolith with weak cation exchange functionalities was prepared in capillary column (i.d. 100 μm, o.d. 375 μm) by in situpolymerization of butyl methacrylate, ethylene dimethacrylate and N‐methacryloyl‐L‐glutamic acid in presence of porogens. The porogen mixture included N,N‐dimethyl formamide and phosphate buffer. The preparation procedure of stationary phase contained the synthesis of monomer, silanization of capillary inner wall and in situpolymerization. The use of amino acid based monomer for the monolith synthesis is one of the originalities of this novel approach. N‐methacryloyl‐L‐glutamic acid has two carboxyl functionalities. The separation of the solutes were performed at different acetonitrile/phosphate buffer and acetonitrile/sodium hydroxide contents. The applied voltage for the alkyl benzenes was changed between +5 and +30 kV. CECseparations of alkyl benzenes, acidic, basic, phenolic and some polycylic aromatic compounds were succesfully performed under capillary‐electrochromatography mode with cathodic electroosmotic flow.

Molecular imprinting is an attractive biomimetic approach that creates specific recognition sites for the shape and functional group arrangement to template molecules. The purpose of this study is to prepare cytochrome c‐imprinted poly(hydroxyethyl methacrylate) (PHEMA)‐based supermacroporous cryogel which can be used for the separation of cytochrome cfrom protein mixtures. N‐Methacryloyl‐(L)‐histidinemethylester (MAH) was used as the metal‐coordinating monomer. In the first step, Cu2+was complexed with MAH, and the cytochrome cimprinted PHEMA (MIP) cryogel was prepared by free radical cryopolymerization initiated by N,N,N′,N′‐tetramethylene diamine at −12°C. After polymerization is completed, the template cytochrome cmolecules were removed from the MIP cryogel using 0.5 M NaCl solution. The maximum cytochrome cbinding amount was 126 mg/g polymer. Selective binding studies were performed in the presence of lysozyme and bovine serum albumin. The relative selectivity coefficients of MIP cryogel for cytochrome c/lysozyme and cytochrome c/bovine serum albumin were 1.7 and 5.2 times greater than those of the non‐imprinted PHEMA cryogel, respectively. The selectivity of MIP cryogel for cytochrome cwas also confirmed with fast protein liquid chromatography. The MIP cryogel could be used many times with no remarkable decrease in cytochrome cbinding capacity.

A new generation of molecularly imprinted macroporous hydrogels, socalled cryogels, were prepared for depletion of hemoglobin from human blood. HbPHEMAH cryogels were prepared with gel fraction yields up to 90, and its morphology and porosity were characterized by FTIR, SEM, swelling studies, flow dynamics and surface area measurements. Selective binding experiments were performed in the presence of competitive proteins Myb and BSA. HbPHEMAH cryogel exhibited a high binding capacity and selectivity for Hb in the presence of Myb and BSA. The selectivity of HbPHEMAH cryogel for Hb was confirmed by HPLC. Hb depletion from blood hemolysate was also studied using SDSPAGE. HbPHEMAH cryogel can be reused many times with no apparent decrease in Hb adsorption capacity.

We prepared poly(ethylene glycol dimethacrylate–1‐vinyl‐1,2,4‐triazole) [poly(EGDMA–VTAZ)] beads (average diameter = 150–200 μm) by copolymerizing ethylene glycol dimethacrylate (EGDMA) with 1‐vinyl‐1,2,4‐triazole (VTAZ). The copolymer composition was characterized by elemental analysis and found to contain five EGDMA monomer units for each VTAZ monomer unit. The poly(EGDMA–VTAZ) beads had a specific surface area of 65.8 m2/g. Poly(EGDMA–VTAZ) beads were characterized by Fourier transform infrared spectroscopy, elemental analysis, surface area measurements, swelling studies, and scanning electron microscopy. Poly(EGDMA–VTAZ) beads with a swelling ratio of 84% were used for the heavy‐metal removal studies. The adsorption capacities of the beads for Cd(II), Hg(II), and Pb(II) were investigated in aqueous media containing different amounts of these ions (5–750 mg/L) and at different pH values (3.0–7.0). The maximum adsorption capacities of the poly(EGDMA–VTAZ) beads were 85.7 mg/g (0.76 mmol/g) for Cd(II), 134.9 mg/g (0.65 mmol/g) for Pb(II), and 186.5 mg/g (0.93 mmol/g) for Hg(II). The affinity order toward triazole groups on a molar basis was observed as follows: Hg(II) > Cd(II) > Pb(II). pH significantly affected the adsorption capacity of the VTAZ‐incorporated beads. The equilibrium data were well fitted to the Redlich–Peterson isotherm. Consideration of the kinetic data suggested that chemisorption processes could have been the rate‐limiting step in the adsorption process. Regeneration of the chelating‐beads was easily performed with 0.1M HNO3. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4276–4283, 2006

We used a molecular imprinting approach to achieve specific metal binding utilizing N‐methacryloyl‐(L)‐cysteine methyl ester (MAC) as a metal‐complexing ligand. MAC was synthesized using methacryloyl chloride and cysteine methyl ester. Then, Fe3+ was complexed with MAC monomer. Fe3+‐imprinted poly(hydroxyethyl methacrylate‐N‐methacryloyl‐(L)‐cysteine methyl ester) [poly(HEMA‐MAC)] beads with average size of 63–140 μm were produced by suspension polymerization. After that, the template ions (i.e. Fe3+ ions) were removed by 0.1M HCl. Fe3+‐imprinted beads were characterized by swelling studies, FTIR, and elemental analysis. The Fe3+‐imprinted beads with a swelling ratio of 72%, and containing 3.9 mmol MAC/g were used in the binding of Fe3+ ions from aqueous solutions, tap water, certified reference serum sample, and real serum sample. Maximum binding capacity, optimum pH, and equilibrium binding time were 107 μmol/g, pH 3.0, and 30 min, respectively. It was observed that even in the presence of other ions, Fe3+‐imprinted beads selectively bound Fe3+ ions with 97% efficiency. Removal of Fe3+ ions from certified reference serum sample was approximately found to be 33%. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3520–3528, 2006

A novel monolithic material was developed to obtain efficient and cost‐effective purification of IgG from human plasma. The porous monolith was obtained by bulk polymerization in a glass tube of 2‐hydroxyethyl methacrylate (HEMA) and N‐methacryloyl‐(L)‐histidine methyl ester (MAH). The poly(HEMA‐MAH) monolith had a specific surface area of 214.6 m2/g and was characterized by swelling studies, porosity measurement, FTIR, scanning electron microscopy, and elemental analysis. Then the monolith was loaded with Cu2+ ions to form the metal chelate. Poly(HEMA‐MAH) monolith with a swelling ratio of 74% and containing 20.9 μmol MAH/g was used in the adsorption/desorption of IgG from aqueous solutions and human plasma. The maximum adsorption of IgG from an aqueous solution in phosphate buffer was 10.8 mg/g at pH 7.0. Higher adsorption was obtained from human plasma (up to 104.2 mg/g), with a purity of 94.1%. It was observed that IgG could be repeatedly adsorbed and desorbed with the poly(HEMA‐MAH) monolith without significant loss of adsorption capacity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 395–404, 2006

We investigated a new adsorbent system, Reactive Red 120 attached poly(2‐hydroxyethyl methacrylate ethylene dimethacrylate) [poly(HEMA–EDMA)] beads, for the removal of Ni2+ ions from aqueous solutions. Poly(HEMA–EDMA) beads were prepared by the modified suspension copolymerization of 2‐hydroxyethyl methacrylate and ethylene dimethacrylate. Reactive Red 120 molecules were covalently attached to the beads. The beads (150–250 μm), having a swelling ratio of 55% and carrying 25.5 μmol of Reactive Red 120/g of polymer, were used in the removal of Ni2+ ions. The adsorption rate and capacity of the Reactive Red 120 attached poly(HEMA–EDMA) beads for Ni2+ ions was investigated in aqueous media containing different amounts of Ni2+ ions (5–35 mg/L) and having different pH values (2.0–7.0). Very high adsorption rates were observed at the beginning, and adsorption equilibria were then gradually achieved in about 60 min. The maximum adsorption of Ni2+ ions onto the Reactive Red 120 attached poly(HEMA–EDMA) beads was 2.83 mg/g at pH 6.0. The nonspecific adsorption of Ni2+ ions onto poly(HEMA–EDMA) beads was negligible (0.1 mg/g). The desorption of Ni2+ ions was studied with 0.1M HNO3. High desorption ratios (>90%) were achieved. The intraparticle diffusion rate constants at various temperatures were calculated as k20°C = 0.565 mg/g min0.5, k30°C = 0.560 mg/g min0.5, and k40°C = 0.385 mg/g min0.5. Adsorption–desorption cycles showed the feasibility of repeated use of this novel adsorbent system. The equilibrium data fitted very well both Langmuir and Freundlich adsorption models. The pseudo‐first‐order kinetic model was used to describe the kinetic data. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:5056–5065, 2006

A magnetic metal−chelate adsorbent utilizing N-methacryloyl-(l)-cysteine methyl ester (MAC) as a metal-chelating ligand was prepared. MAC was synthesized using methacryloyl chloride and l-cysteine methyl ester dihydrochloride. Magnetic beads with an average size of 150−250 m were obtained by suspension polymerization of 2-hydroxyethyl methacrylate (HEMA) and MAC carried out in a dispersion medium. Mag-poly(HEMA−MAC) beads were characterized by surface area measurements, swelling tests, electron spin resonance (ESR) spectroscopy, elemental analysis, and scanning electron microscopy (SEM). The specific surface area of the magnetic beads was found to be 92.6 m2/g. Elemental analysis of MAC for nitrogen was estimated as 55.4 mol/g. Then, Fe3ions were chelated on the magnetic beads. The Fe3loading was 12.7 mol/g of support. Fe3-chelated magnetic beads with a swelling ratio of 62% were used in the immobilization of catalase in a batch system. This approach to the preparation of enzyme carrier has several advantages over conventional immobilization methods. An expensive, time-consuming, and critical step in the preparation of immobilized metal-affinity carriers is the coupling of a chelating ligand to the adsorption matrix. In this procedure, comonomer MAC acts as the metal-chelating ligand, and it is possible to load metal ions directly on the beads without further modification steps. The maximum catalase immobilization capacity of the mag-poly(HEMA−MAC)−Fe3beads was observed to be 192 mg/g at pH 5.5. The Kmvalue for immobilized catalase mag-poly(HEMA−MAC)−Fe3 (32.6 mM) was higher than that for free catalase (22.8 mM). Immobilized catalase exhibits enhanced stability in reaction conditions over a wide pH range (pH 5.5−7.0) and retains an activity of 76% after 10 successive batch reactions, demonstrating the usefulness of the enzyme-loaded magnetic beads in biocatalytic applications. The optimum temperature for the immobilized preparation of mag-poly(HEMA−MAC)−Fe3−catalase at 45 °C was 5 °C higher than that of the free enzyme at 40 °C. Storage stability was found to increase with immobilization.

N‐methacryloyl‐(L)‐alanine (MALA) was synthesized by using methacryloyl chloride and alanine as a metal‐complexing ligand or comonomer. Spherical beads with an average diameter of 150–200 μm were obtained by suspension polymerization of MALA and 2‐hydroxyethyl methacrylate (HEMA) conducted in an aqueous dispersion medium. Poly(HEMA–MALA) beads were characterized by SEM, swelling studies, surface area measurement, and elemental analysis. Poly(HEMA–MALA) beads have a specific surface area of 68.5 m2/g. Poly(HEMA–MALA) beads with a swelling ratio of 63%, and containing 247 μmol MALA/g were used in the removal of Hg2+ from aqueous solutions. Adsorption equilibrium was achieved in about 60 min. The adsorption of Hg2+ ions onto PHEMA beads was negligible (0.3 mg/g). The MALA incorporation into the polymer structure significantly increased the mercury adsorption capacity (168 mg/g). Adsorption capacity of MALA containing beads increased significantly with pH. The adsorption of Hg2+ ions increased with increasing pH and reached a plateau value at around pH 5.0. Competitive heavy metal adsorption from aqueous solutions containing Cd2+, Cu2+, Pb2+, and Hg2+ was also investigated. The adsorption capacities are 44.5 mg/g for Hg2+, 6.4 mg/g for Cd2+, 2.9 mg/g for Pb2+, and 2.0 mg/g for Cu2+ ions. These results may be considered as an indication of higher specificity of the poly(HEMA–MALA) beads for the Hg2+ comparing to other ions. Consecutive adsorption and elution operations showed the feasibility of repeated use for poly(HEMA–MALA) chelating beads. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1222–1228, 2006

The aim of this study is to prepare ion-imprinted polymers that can be used for the selective removal of aluminum ions [Al3+] from aqueous solutions. N-Methacryloyl-l-glutamic acid (MAGA) was chosen as the complexing monomer. In the first step, Al3+ was complexed with MAGA and Al3+-imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-l-glutamic acid) (MIP) beads were synthesized by suspension polymerization. After that, the template ions (i.e., Al3+) were removed using 0.1 M EDTA solution. The specific surface area of the MIP beads was found to be 55.6 m2/g with a size range of 63−140 μm in diameter, and the swelling ratio was 102%. According to the elemental analysis results, the MIP beads contained 640 μmol of MAGA/g of polymer. The maximum adsorption capacity was 122.9 μmol of Al3+/g of beads. The applicability of two kinetic models including pseudo-first-order and pseudo-second-order models 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 adsorption process. The relative selectivity coefficients of MIP beads for Al3+/Ni2+, Al3+/Cu2+, and Al3+/Fe3+ were respectively 1427, 14.8, and 6.2 times greater than that of the nonimprinted matrix. The MIP beads could be used many times without significantly decreasing in their adsorption capacities.

Metal‐chelating membranes have advantages as adsorbents in comparison with conventional beads because they are not compressible and they eliminate internal diffusion limitations. The aim of this study was to explore in detail the performance of poly(2‐hydroxyethyl methacrylate–methacryloylamidohistidine) [poly(HEMA–MAH)] membranes for the removal of three toxic heavy‐metal ions—Cd(II), Pb(II), and Hg(II)—from aquatic systems. The poly(HEMA–MAH) membranes were characterized with scanning electron microscopy and 1H‐NMR spectroscopy. The adsorption capacity of the poly(HEMA–MAH) membranes for the selected heavy‐metal ions from aqueous media containing different amounts of these ions (30–500 mg/L) and at different pH values (3.0–7.0) was investigated. The adsorption capacity of the membranes increased with time during the first 60 min and then leveled off toward the equilibrium adsorption. The maximum amounts of the heavy‐metal ions adsorbed were 8.2, 31.5, and 23.2 mg/g for Cd(II), Pb(II), and Hg(II), respectively. The competitive adsorption of the metal ions was also studied. When the metal ions competed, the adsorbed amounts were 2.9 mg of Cd(II)/g, 14.8 mg of Pb(II)/g, and 9.4 mg of Hg(II)/g. The poly(HEMA–MAH) membranes could be regenerated via washing with a solution of nitric acid (0.01M). The desorption ratio was as high as 97%. These membranes were suitable for repeated use for more than three adsorption/desorption cycles with negligible loss in the adsorption capacity. The stability constants for the metal‐ion/2‐methacryloylamidohistidine complexes were calculated to be 3.47 × 106, 7.75 × 107, and 2.01 × 107 L/mol for Cd(II), Pb(II), and Hg(II) ions, respectively, with the Ruzic method. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1213–1219, 2005

Concanavalin A (Con A) immobilized poly(2‐hydroxyethyl methacrylate) (PHEMA) beads in a spherical form (100–150 μm in diameter) were used for the affinity chromatography purification of human immunoglobulin G (IgG) from aqueous solutions and human plasma. PHEMA adsorbents were prepared by suspension polymerization. Bioligand Con A was then immobilized by covalent binding onto PHEMA beads. The maximum IgG adsorption on the PHEMA/Con A beads was observed at pH 6.0. The nonspecific IgG adsorption onto the plain PHEMA adsorbents was very low (ca. 0.17 mg/g). Higher adsorption values (up to 54.3 mg/g) were obtained when the PHEMA/Con A beads were used from aqueous solutions. A higher adsorption capacity was observed for human plasma (up to 69.4 mg/g) with a purity of 82.5%. The adsorption capacities of other blood proteins were 2.0 mg/g for fibrinogen and 4.2 mg/g for albumin. The total protein adsorption was determined to be 76.0 mg/g. IgG molecules could be repeatedly adsorbed and desorbed with the PHEMA/Con A beads without noticeable loss in the IgG adsorption capacity. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1202–1208, 2005

N‐Methacryloyl‐(L)‐histidine methyl ester (MAH) was synthesized from metharyloyl chloride and histidine. Spherical beads with an average size of 150–250 μm were obtained by the suspension polymerization of ethylene glycol dimethacrylate and MAH in an aqueous dispersion medium. Magnetic poly(ethylene glycol dimethacrylate‐co‐N‐Methacryloyl‐(L)‐histidine methyl ester) [m‐p(EGDMA‐co‐MAH)] microbeads were characterized with swelling tests, electron spin resonance, elemental analysis, and scanning electron microscopy. The specific surface area of the beads was 80.1 m2/g. m‐p(EGDMA‐co‐MAH) microbeads with a swelling ratio of 40.2% and 43.9 μmol of MAH/g were used for the adsorption of bovine serum albumin (BSA) in a batch system. The Cu(II) concentration was 4.1 μmol/g. The adsorption capacity of BSA on the Cu(II)‐incorporated beads was 19.2 mg of BSA/g. The BSA adsorption first increased with the BSA concentration and then reached a plateau, which was about 19.2 mg of BSA/g. The maximum adsorption was observed at pH 5.0, which was the isoelectric point of BSA. The BSA adsorption increased with decreasing temperature, and the maximum adsorption was achieved at 4°C. High desorption ratios (>90% of the adsorbed BSA) were achieved with 1.0M NaSCN (pH 8.0) in 30 min. The nonspecific adsorption of BSA onto the m‐p(EGDMA‐co‐MAH) beads was negligible. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2669–2677, 2004

Magnetic poly(2‐hydroxyethylmethacrylate) (mPHEMA) beads are modified by iminodiacetic acid (IDA) to implify the reactive groups and subsequent binding of Cu2+ ions to form metal chelate. mPHEMA beads, in the size range of 80–120 μm, were produced by a modified suspension polymerization technique. mPHEMA beads were characterized by swelling tests, electron spin resonance (ESR), FTIR, and scanning electron microscopy (SEM). Important results obtained in this study are as follows. The swelling ratio of mPHEMA beads was 34%. The presence of magnetite particles in the polymeric structure was confirmed by ESR. FTIR data confirmed that the magnetic polymer beads were modified with functional groups IDA. The mPHEMA beads have a spherical shape and porous structure. The effect of pH and concentration of human serum albumin (HSA), on the adsorption of HSA to the metal‐chelated magnetic beads, were examined in a batch reactor. Most importantly, the magnetic beads had little nonspecific adsorption for HSA (0.5 mg/g) before introducing IDA groups. Cu2+ chelation increased the HSA adsorption up to 28.4 mg/g. Adsorption behavior can be described at least approximately with the Langmuir equation. Regeneration of the metal‐chelated magnetic beads was easily performed with 1.0M NaSCN, pH 8.0, followed by washing with distilled water and reloading with Cu2+. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2501–2510, 2004

Lysozyme adsorption onto Cibacron Blue F3GA incorporated magnetic poly(2-hydroxyethyl methacrylate) (mag-PHEMA) beads was investigated. Mag-PHEMA beads (80–120 μm) were produced by dispersion polymerization. The triazine dye Cibacron Blue F3GA was incorporated covalently as a dye ligand. These dye-incorporated beads, having a swelling ratio of 34% (w/w) and carrying different amounts of Cibacron Blue F3GA (12.2–42.8 μmol/g) were used in lysozyme adsorption studies. The effects of the initial concentration, pH, ionic strength, and temperature on the adsorption efficiency of dye-incorporated beads were studied in a batch reactor. The effects of the Cibacron Blue F3GA loading on the lysozyme adsorption were also studied. The nonspecific adsorption of lysozyme on the mag-PHEMA beads was 0.8 mg/g. Cibacron Blue F3GA attachment significantly increased the lysozyme adsorption up to 295 mg/g. More than 90% of the adsorbed lysozyme was desorbed in 1 h in a desorption medium containing 1.0M KSCN at pH 8.0. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 719–725, 2004

The removal of silver ions from aqueous solutions containing low-to-moderate levels of contamination using Turkish Beypazari low-rank coal was investigated. Carboxylic acid and phenolic hydroxyl functional groups present on the coal surface provided adsorption sites for the removal of silver ions from solution via ion exchange. The equilibrium pH of the coal/solution mixture was shown to be the principal factor controlling the extent of recovery of Ag+ions from aqueous solutions. The optimum pH was measured as 4.0 and it was found that the maximum removal of silver from solution was achieved within 30 min. The maximum adsorption capacity of the Ag+ions was 1.87 mg/g coal. The adsorption phenomena appeared to follow a typical Langmuir isotherm. It was observed that the use of low-rank coal was considerably more effective in the recovery Ag+ions from aqueous solutions. Higher amounts of adsorbed Ag+ions could be desorbed (up to 92%) using 25 mM EDTA. Low-rank Turkish coals were suitable for consecutive use for more than 10 cycles without significant loss of adsorption capacity.

An affinity dye ligand, Cibacron Blue F3GA, was covalently attached onto magnetic poly(2-hydroxyethyl methacrylate) (mPHEMA) beads for human serum albumin (HSA) adsorption from both aqueous solutions and human plasma. The mPHEMA beads, in the size range of 80 to 120 µm, were prepared by a modified suspension technique. Cibacron Blue F3GA molecules were incorporated on to the mPHEMA beads. The maximum amount of Cibacron Blue F3GA attachment was obtained as 68.3 µmol g⁻¹. HSA adsorption onto unmodified and Cibacron Blue F3GA-attached mPHEMA beads was investigated batchwise. The non-specific adsorption of HSA was very low (1.8 mg g⁻¹). Cibacron Blue F3GA attachment onto the beads significantly increased the HSA adsorption (94.5 mg g⁻¹). The maximum HSA adsorption was observed at pH 5.0. Higher HSA adsorption was observed from human plasma (138.3 mg HSA g⁻¹). Desorption of HSA from Cibacron Blue F3GA-attached mPHEMA beads was obtained by using 0.1 M Tris/HCl buffer containing 0.5 M NaSCN. High desorption ratios (up to 98% of the adsorbed HSA) were observed. It was possible to re-use Cibacron Blue F3GA-attached mPHEMA beads without any significant decreases in their adsorption capacities. Copyright © 2004 Society of Chemical Industry