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Molecularly imprinted polymers which have been extensively investigated as selective adsorbents were constructed using a template molecule during the polymerization to gain template-specific cavities. In this study, we prepared cholesterol imprinted poly(2-hydroxyethyl methacrylate-methacryloyamidotryptophan) (PHEMA-MTrp) particles embedded composite membranes. These membranes were characterized through elemental analysis, FTIR, SEM, swelling tests, and surface area measurements. Adsorption experiments were performed in a batch experimental set-up, and the adsorption medium was either a methanol or intestinal-mimicking solution. Stigmasterol and estradiol were used as competing molecules in selectivity tests. Some results are as follows: the specific surface areas of MIP particle-embedded membranes, NIP particle-embedded membranes, and membranes without particles were 36.5, 29.2 and 13.7 m 2 /g, respectively. The imprinted membranes were 1.96 and 2.13 times more selective for cholesterol when compared to stigmasterol and estradiol used as competitor agents, respectively. Cholesterol adsorption capacity increased up to 23.43 mg/g with increasing cholesterol concentration of 2 mg/mL. The MIP particle-embedded composite membranes showed a negligible loss in cholesterol adsorption capacity after ten consecutive adsorption cycles using the same adsorbent. [ABSTRACT FROM AUTHOR]

Highlights: [•] Simultaneous depletion of immunoglobulin G and albumin from human plasma. [•] Novel monolithic cryogel columns for co-depletion of high abundant proteins. [•] IgG was targeted via protein A meanwhile albumin was targeted via cibacron blue F3GA. [•] The plasma samples were assayed with SDS-PAGE to analyze the depletion efficiency. [•] Promising candidate for blood-related proteomics in not only lab scale but also preparative scale. [ABSTRACT FROM AUTHOR]

Abstract: In this study, it was aimed to prepare hydrophobic cryogels for plasmid DNA (pDNA) purification from Escherichia coli lysate. The hydrophobicity was achieved by incorporating a hydrophobic ligand, N-methacryloyl-(l)-phenylalanine (MAPA), into the cryogel backbone. In addition to the conventional cryogelation process, freeze-drying step was included to create nanospines. Three different cryogels {poly(2-hydoxyethyl methacrylate-N-methacryloyl-l-phenylalanine)-freeze dried, [P(HEMA-MAPA)-FD]; poly(2-hydoxyethyl methacrylate-N-methacryloyl-l-phenylalanine, [P(HEMA-MAPA)] and poly(2-hydoxyethyl methacrylate)-freeze dried, [P(HEMA)-FD]} were prepared, characterized, and used for DNA (salmon sperm DNA) adsorption studies from aqueous solution. The specific surface areas of cryogels were determined to be 21.4m2/g for P(HEMA)-FD, 17.65m2/g for P(HEMA-MAPA) and 36.0m2/g for P(HEMA-MAPA)-FD. The parameters affecting adsorption such as temperature, initial DNA concentration, salt type and concentration were examined in continuous mode. The maximum adsorption capacities were observed as 45.31mg DNA/g, 27.08mg DNA/g and 1.81mg DNA/g for P(HEMA-MAPA)-FD, P(HEMA-MAPA) and P(HEMA)-FD, respectively. Desorption process was performed using acetate buffer (pH 5.50) without salt. First, pDNA was isolated from E. coli lysate and the purity of pDNA was then determined by agarose gel electrophoresis. Finally, the chromatographic performance of P(HEMA-MAPA)-FD cryogel for pDNA purification was tested in FPLC. The resolution (R s) was 2.84, and the specific selectivity for pDNA was 237.5-folds greater than all impurities. [Copyright &y& Elsevier]

In this study, a nanoparticle-based sandwich-like immunoassay was designed in dispersion medium to precisely detect apoptosis over caspase antibodies in order to overcome the disadvantages of traditional apoptosis determination methods such as high cost, large sampling requirement, and appropriate laboratory and equipment conditions. For this purpose, a complementary particulate system including magnetic (MNPs) and upconversion silica (UC-SiNPs) nanoparticles while immobilizing antibodies (primary antibody to MNPs, secondary antibody to UC-SiNPs) were synthesized and characterized. Optimization and selectivity studies of the complex formed by primary antibody immobilized MNPs with standard caspase proteins were examined by the HPLC system. Within the scope of optimization studies, protein concentrations, optimal duration, and temperature parameters were evaluated. Optimal conditions were determined for pH, initial concentration, time, and temperature as 7.4, 5.6 μg/mL, 45 min, and room temperature, respectively. Furthermore, the adsorption of competitive proteins was investigated in selectivity studies as well. Moreover, the primary antibody immobilized MNPs were treated with standard caspase proteins under optimal conditions; subsequently, they were interacted with secondary antibody immobilized UC-SiNPs to demonstrate the supracomplex formation meanwhile zeta potential/size measurements and fluorescence emission spectrometry analyses were performed. As a result of these analyses, it was observed that the sandwich-like supracomplexes were successfully formed that significantly varied upconversion emission intensities of UC-SiNPs in dependence on the amounts of caspase proteins. Because this approach enabled a quantitative result, the nanoparticle-based sandwich-like immunoassay should be classified as an easy-to-handled, fast, and promising alternative to benchmark apoptosis assays. [Display omitted] • A complementary nanoparticle-based sandwich-like immunoassay for caspases. • Decorating magnetic and upconversion silica nanoparticles with primary caspase and secondary antibodies. • One-to-one monovalent combination observed during sandwich-like supracomplex formation. • Significant decrease in fluorescent emission intensities with the increasing analyte concentration. • Easy-to-handled, fast, and promising alternative to benchmark apoptosis assays. [ABSTRACT FROM AUTHOR]

Surface imprinting strategy is one of the promising approaches to synthesize plastic antibodies while overcoming the problems in the protein imprinting research. In this study, we focused our attentions on developing two-step polymerization to imprint on the bare surface employing polyethyleneimine (PEI) assisted-coordination of template molecules, lysozyme. For this aim, we firstly synthesized poly(2-hydroxyethyl methacrylate-glycidyl methacrylate), poly(HEMA-GMA) cryogels as a bare structure. Then, we immobilized PEI onto the cryogels through the addition reaction between GMA and PEI molecules. After that, we determined the amount of free amine (NH 2 ) groups of PEI molecules, subsequently immobilized methacrylate functionalities onto the half of them and another half was used to chelate Cu(II) ions as a mediator between template, lysozyme and PEI groups. After the characterization of the materials developed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and the micro-computed tomography (μCT), we optimized the lysozyme adsorption conditions from aqueous solution. Before performing lysozyme purification from chicken egg white, we evaluated the effects of pH, interaction time, the initial lysozyme concentration, temperature and ionic strength on the lysozyme adsorption. Moreover, the selectivity of surface imprinted cryogels was examined against cytochrome c and bovine serum albumin (BSA) as the competitors. Finally, the mathematical modeling, which was applied to describe the adsorption process, showed that the experimental data is very well-fitted to the Langmuir adsorption isotherm. [ABSTRACT FROM AUTHOR]

Molecular imprinting is a polymerization technique that provides synthetic analogs for template molecules. Molecularly imprinted polymers (MIPs) have gained much attention due to their unique properties such as selectivity and specificity for target molecules. In this study, we focused on the development of polymeric materials with molecular recognition ability, so molecular imprinting was combined with miniemulsion polymerization to synthesize self-orienting nanoparticles through the use of an epitope imprinting approach. Thus, l -lysine imprinted nanoparticles (LMIP) were synthesized via miniemulsion polymerization technique. Immunoglobulin G (IgG) was then bound to the cavities that specifically formed for l -lysine molecules that are typically found at the C-terminus of the Fc region of antibody molecules. The resulting nanoparticles makes it possible to minimize the nonspecific interaction between monomer and template molecules. In addition, the orientation of the entire IgG molecule was controlled, and random imprinting of the IgG was prevented. The optimum conditions were determined for IgG recognition using the imprinted nanoparticles. The selectivity of the nanoparticles against IgG molecules was also evaluated using albumin and hemoglobin as competitor molecules. In order to show the self-orientation capability of imprinted nanoparticles, human serum albumin (HSA) adsorption onto both the plain nanoparticles and immobilized nanoparticles by anti-human serum albumin antibody (anti-HSA antibody) was also carried out. Due to anti-HSA antibody immobilization on the imprinted nanoparticles, the adsorption capability of nanoparticles against HSA molecules vigorously enhanced. It is proved that the oriented immobilization of antibodies was appropriately succeeded. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fast, controllable and simple preparation of the modified surfaces was performed. [•] CB modified PGEs was used for the first time in the literature for dye–protein interaction. [•] Alternative route was shown compared to classical time-consuming methods. [•] Good selectivity and sensitivity were obtained for CB–BSA interaction. [Copyright &y& Elsevier]

• Hydrophilic and hydrophobic amino acid conjugated SAMs were synthesized. • Modification of PDMS with SAMs were optimized and characterized by XPS and WCA. • Osteoblast proliferation, morphology and maturation on PDMS were investigated. • Both SAMs provided improved cell responses, but hydrophilic His-APTES was superior. Polydimethylsiloxane (PDMS) is a biocompatible synthetic polymer and used in various applications due to its low toxicity and tunable surface properties. However, PDMS does not have any chemical cues for cell binding. Plasma treatment, protein coating or surface modification with various molecules have been used to improve its surface characteristics. Still, these techniques are either last for a very limited time or have very complicated experimental procedures. In the present study, simple and one-step surface modification of PDMS is successfully accomplished by the preparation of hydrophilic and hydrophobic amino acid conjugated self-assembled monolayers (SAMs) for enhanced interactions at the cell-substrate interface. Synthesis of histidine and leucine conjugated (3-aminopropyl)-triethoxysilane (His-APTES and Leu-APTES) were confirmed with proton nuclear magnetic resonance spectroscopy (1H NMR) and optimum conditions for the modification of PDMS with SAMs were investigated by X-ray photoelectron spectroscopy (XPS) analysis, combined with water contact angle (WCA) measurements. Results indicated that both SAMs enhanced cellular behavior in vitro. Furthermore, hydrophilic His-APTES modification provides a superior environment for the osteoblast maturation with higher alkaline phosphatase activity and mineralization. As histidine, leucine, and functional groups of these SAMs are naturally found in biological systems, modification of PDMS with them increases its cell-substrate surface biomimetic properties. This study establishes a successful modification of PDMS for in vitro cell studies, offering a biomimetic and easy procedure for potential applications in microfluidics, cell-based therapies, or drug investigations. [ABSTRACT FROM AUTHOR]

Cryogels are used effectively for many diverse applications in a variety of fields. The isolation or purification of RNA, one of the potential utilizations for cryogels, is crucial due to their vital roles such as encoding, decoding, transcription and translation, and gene expression. RNA principally exists within every living thing, but their tendency to denaturation easily is still the most challenging issue. Herein, we aimed to develop adenine incorporated polymeric cryogels as an alternative sorbent for cost-friendly and fast RNA purification with high capacity. For this goal, we synthesized the polymerizable derivative of adenine called as adenine methacrylate (AdeM) through the substitution reaction between adenine and methacryloyl chloride. Then, 2-hydroxyethyl methacrylate (HEMA)-based cryogels were prepared in a partially frozen aqueous medium by copolymerization of monomers, AdeM, and HEMA. The cryogels were characterized by using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), surface area measurements, thermogravimetric analysis (TGA), and swelling tests. RNA adsorption experiments were performed via batch system while varying different conditions including pH, initial RNA concentration, temperature, and interaction time. We achieved high RNA adsorption capacity of cryogels, with the swelling ratio around 510%, as 11.86 mg/g. The cryogels might be reused at least five times without significant decrease in adsorption capacity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Aspartic acid incorporated novel monolithic columns. [•] The monolithic columns were synthesised in a stainless steel HPLC columns. [•] Characterisation by swelling studies, FTIR and SEM. [•] The monolithic columns for the adsorption/desorption of IgG from aqueous solutions. [•] One-step IgG purification with negligible capacity decrease after ten cycles. [Copyright &y& Elsevier]

Highlights: [•] Bioinspired surface modification of polymers via direct polymerization of dopamine. [•] The catechol functional groups of dopamine have the ability to form strong adhesive bonds. [•] Polydopamine plays essential role in adhesion both onto the microbeads and analyte biomolecules. [•] IgG adsorption capacities increased from 3.71mg/g to 74.21mg/g with dopamine modification. [•] Monolayer Langmuir adsorption model can be thought more applicable for this adsorbent systems. [Copyright &y& Elsevier]

Abstract: Affinity adsorption technique is increasingly used for protein purification, separation and other biochemical applications. Therapeutic molecules such as antibodies, cytokines, therapeutic DNA and plasma proteins must be purified before characterization and utilization. The aim of this study was to prepare micronsized spherical polymeric beads and to investigate the extent of their human insulin adsorption capability. Monosize poly(ethylene glycol dimethacrylate–N-methacryloyl-(l)-histidine) [poly(EDMA–MAH)] beads were prepared by modified suspension copolymerization. Functional monomer (MAH) was synthesized using methacryloyl chloride and l-histidine. The beads were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, swelling test and elemental analysis. MAH incorporation into monosize polymeric beads, having an average size around 2–3μm, was estimated as 55.3μmolMAH/g bead. Equilibrium swelling ratios of poly(EDMA–MAH) and poly(EDMA) beads were 65% and 55%, respectively. Adsorption experiments were performed under different conditions (i.e., pH, temperature, protein concentration and ionic strength). It was found that adsorption characteristics are strongly depend on these conditions. Maximum insulin adsorption capacity was achieved as 24.7mginsulin/g poly(EDMA–MAH) beads. Results were well fitted to the Langmuir isotherm model. Compared with poly(EDMA–MAH), nonspecific insulin adsorption onto poly(EDMA) beads was very low (0.61mginsulin/g bead) and can be negligible. It was observed that insulin could be repeatedly adsorbed and desorbed (at least 10 times) without significant loss in adsorption capacity. [Copyright &y& Elsevier]

• A new strategy to design interface imprinted polymers via utilizing sacrificial metal oxide particles. • Creating selective recognition cavities on / near inside of the polymer surfaces. • A simultaneous removal of the template and sacrificial particles in a single-step treatment. • The interface MIMs with high specific rebinding capacity and excellent selectivity. • Adsorption and kinetic parameters were analyzed via diverse isotherm and kinetic models. In this study, we introduced a new strategy to design interface imprinted polymers for a novel aspect of molecular imprinting technique, utilization of sacrificial metal oxide particles. In the first step, bovine hemoglobin (BHb) was adsorbed on zinc oxide (ZnO) particles, which were then used to synthesize polyacrylic acid-based molecular imprinting membrane by bulk polymerization in the presence of ethylene glycol dimethacrylate as a cross-linking agent. After polymerization terminated, BHb-ZnO particles were removed to leave effective imprint sites onto the bulk polymeric network which is responsible for the formation of template orientation. The characterization of membranes was investigated by using Fourier transform infrared (FTIR), Raman spectroscopy (RS), scanning electron microscopy (SEM), surface area measurements (BET analyses) and thermogravimetric analysis (TGA). The interface molecularly imprinted membranes (iMIMs) have a relatively high specific rebinding capacity of 65.98 mg/g and excellent selectivity towards BHb with a separation factor of 6.78. The equilibrium adsorption isotherms fitted well to Langmuir isotherms (R2 = 0.9944) and the value of adsorption capability (Q max) and equilibrium constant (b) were estimated to be 73.53 mg/g and 1.36 mg/mL for the iMIM, respectively. The kinetics of adsorption fitted best to pseudo-second order (R2 = 0.9912). The ZnO particles were used not only to ensure the preservation of the imprint cavities in the polymer network but also to lead to high template removal and better rebinding kinetics. This novel design with multiple recognition sites is quite simple and suitable for the separation of biomacromolecules. [ABSTRACT FROM AUTHOR]