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The imprinted polymers were prepared to absorb dichlorophen (DCP) by using mesoporous silica with ordered pores and high specific surface area. Both scanning electron microscopy and transmission electron microscopy results suggested that the mesoporous silica nanosphere pores had a periodic distribution. The imprinted layer of polymers was thin and uniform. The adsorption experiments showed that the adsorption of imprinted polymers was obviously improved due to the presence of mesoporous structure. The maximum adsorption capacity of MSNs@MIPs at 318 K was 91.1 mg/g, and the adsorption process rapidly reached the equilibrium within 40 min. The adsorption isotherm was well fitted by the Freundlich isotherm model, indicating that multimolecular layer adsorption mechanism governs the adsorption of DCP by the polymers. The adsorption of MSNs@MIPs complied with pseudo-second-order kinetic model. Both selective and regenerative experiments demonstrated that MSNs@MIPs can be successfully applied for selective adsorption of DCP.

Investigation of the effect of the polymer synthesis method on physicochemical properties of sorbents is one of the topical problems in the chemistry of macromolecular compounds that has high scientific and practical interest. Determination of the optimal synthesis method will make it possible to create sorbents with physicochemical properties that led to the realization of effective sorption. In this work, we investigated the effect of synthesis methods (Pickering emulsion polymerization and precipitation polymerization in solution) of granular polymers based on 2-hydroxyethyl methacrylate and ethylene glycol dimethacrylate on physicochemical and sorption properties. The synthesis by Pickering emulsion polymerization led to improvement of the n-propyl alcohol diffusion into the polymer network and to the formation of more homogeneous and structurally stable polymer networks. Creating selective polymer networks by Pickering emulsion polymerization compared to precipitation polymerization in solution led to an increase in porosity, creation of more segregated surface of granules, improvement of binding sites availability at the temperature of 37 °C, and formation of the homogeneous sorption surface with high affinity to target molecules at 25 °C and 37 °C. Selective polymers synthesized by both polymerization methods had the largest values of available sorption surfaces areas for target molecules at 37 °C.

In this study, we have reported a novel wastewater treatment technique by phenol imprinted bacterial cellulose (BC-MIP) nanofibres with high specificity and adsorption capacity. N-methacryloyl-(L) phenylalanine methyl ester (MAPA) functional monomer was used to create specific binding sites for the template molecule phenol via electrostatic and hydrophobic interactions. BC-MIP nanofibres were synthesized by surface imprinting approach in the presence of different amounts of total monomer (% weight), monomer/template ratio and polymerization time. Then, the nanofibres were characterized by FTIR-ATR, surface area analysis (BET), elemental analysis, scanning electron microscopy (SEM) and contact angle measurements. Adsorption studies were performed with respect to pH, temperature and ionic strength, and the adsorption capacity was calculated by using the spectrophotometer. In order to desorb the adsorbed phenol from BC-MIP nanofibres, 0.1 M NaCl solution was used. Besides, BC-MIP nanofibres were applied to real wastewater samples from Ergene basin in Turkey. The suitable equilibrium isotherm was determined as Langmuir isotherm. To evaluate the selectivity of the BC-MIP nanofibres, similar molecules were utilized as competitor molecules, which were 2-chlorophenol, 4-chlorophenol and 2,4-dichlorophenol. Electrostatic interactions were found to contribute to the generation of specific recognition binding sites. The results have shown that imprinting of phenol was achieved successfully with high adsorption capacity. The phenol removal efficiency was reported up to 97%. BC-MIP nanofibres were used 10 times with a negligible decrease in adsorption capacity. [GRAPHICS] . WOS:000471539100001 2-s2.0-85065257535 PubMed: 30919740

Inducing residual stress in metallic glasses (MGs) is recognized to be beneficial for plasticity but the mechanisms on how it affects shear band nucleation, propagation and multiplication remain poorly understood. With the aid of experimental and computational approaches, we address this issue by comparatively studying the deformation behavior of two types of MG samples, which were individually prepared by surface imprinting and photo-chemical etching but having similar surface patterns. Results showed that the imprinted MGs exhibit simultaneously enhanced plasticity and compressive strength, while the etched ones show limited plasticity improvement and reduced strength. The enhanced mechanical properties of the imprinted MGs are attributed to the compressive residual stresses generated near the surfaces, rather than the resultant geometrical pits. Finite element analysis revealed that the residual stress induces obvious stress gradient and inhomogeneous plastic deformation, which facilitate heterogeneous nucleation of multiple shear bands near the surfaces. Complementary atomistic simulations further revealed that the stress gradient resulting from the residual stress slows down the shear banding dynamics and causes deflection and branching, which consequently promotes shear band multiplication during propagation. This work uncovers the interactions between the residual stresses and shear bands, which are useful for processing MGs with desirable mechanical properties.

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

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 (NH2) 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 (?CT), 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. © 2016 Elsevier B.V.

In this research, a novel, sulfamethazine, thermosensitive, molecularly-imprinted polymer (MIP) with an obvious core&ndash, shell structure for the enrichment of sulfamethazine (SMZ), which involved temperature sensitive monomer N-Isopropylacrylamide, functional monomer methacrylic acid and cross-linking agents ethyleneglycol dimethacrylate (EGDMA) and N,N&prime, methylenebisacrylamide, was successfully compounded using the surface polymerization method. To ensure the best experimental group, we designed and compared three groups of controlled experiments of MIPs with different crosslinking agents. When the adsorption temperature was almost the lower critical solution temperature (LCST) of Poly(N-Isopropylacrylamide), the preparative MIPs showed outstanding adsorption capacity and specific identification to sulfamethazine. Moreover, this allowed the MIPs to better facilitate by combining the template molecules, as well as optimizing the imprinting factor. In addition, after 80 min, the adsorption of the MIPs leveled off and remained constant, and the adsorption quantity reached (a maximum of) at 8.1 mg&middot, g&minus, 1.

Today, surface imprinted polymers emerge as synthetic adsorbents with application in several areas. In this study, adsorptions of Cu(II) ion and model protein (lysozyme) from aqueous solution were investigated using Cu(II) ion and lysozyme imprinted poly(HEMA-GMA) cryogels via batch wise experiments. Polyethyleneimine (PEI) was used as ligand for the polymeric structure. Binding of Cu(II) ions into the structure was achieved via electrostatic interactions and adsorption of lysozyme was performed under favor of Cu(II) ions bounded to the structure. Characterization of poly(HEMA-GMA) cryogels was conducted via Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and microcomputerized tomography (μCT). The amount of Cu(II) ions before and after adsorption process was estimated using atomic absorption spectroscopy (AAS) whereas that of lysozyme molecules was determined using UV-visible spectroscopy. Yüzey baskılanmış polimerler, günümüzde çok çeşitli alanlarda kendine yer bulan sentetik adsorbentler olarak karşımıza çıkmaktadır. Bu çalışmada, Cu(II) iyonunun ve model proteinin (lizozim), sulu çözeltilerden Cu(II) ve lizozim yüzey baskılanmış poli(HEMA-GMA) kriyojeller ile adsorpsiyonu kesikli sistem ile araştırılmıştır. Polimerik yapıda ligand olarak polietilenimin (PEI) molekülü kullanılmıştır. Cu(II) iyonunun yapıya bağlanması elektrostatik etkileşimler vasıtasıyla gerçekleştirilmiş olup yapıya bağlanan Cu(II) iyonları sayesinde lizozim proteininin adsorpsiyonu sağlanmıştır. Hazırlanan poli(HEMA-GMA) kriyojeller; Fourier dönüşümlü infrared spektroskopisi (FTIR), taramalı elektron mikroskobu (SEM) ve bilgisayarlı mikrotomografi (μCT) ile karakterize edilmiştir. Adsorpsiyondan önceki ve sonraki Cu(II) iyonlarının miktarı atomik absorpsiyon spektrometresi (AAS) ile lizozim iyonlarının miktarı ise UV-görünür spektrofotometresi ile ölçülmüştür.

A technique for coating microplate wells with molecularly imprinted polymers (MIPs) specific for proteins is presented. 3-Aminophenylboronic acid was polymerized in the presence of the following templates: microperoxidase, horseradish peroxidase, lactoperoxidase, and hemoglobin, via oxidation of the monomer by ammonium persulfate. This process resulted in the grafting of a thin polymer layer to the polystyrene surface of the microplates. Imprinting resulted in an increased affinity of the polymer toward the corresponding templates. The influence of the washing procedure, template concentration, and buffer pH on the polymer affinity was analyzed. It was shown that the stabilizing function of the support and spatial orientation of the polymer chains and template functional groups are the major factors affecting the imprint formation and template recognition. Easy preparation of the MIPs, their high stability, and their ability to recognize small and large proteins, as well as to discriminate molecules with small variations in charge, make this approach attractive and broadly applicable in biotechnology, assays and sensors.

Dissertação para obtenção do Grau de Doutor em Química Sustentável Cardiovascular diseases (CVD) are top-killer chronic diseases, accounting for al-most half of the European deaths in 2010 (Eurostat data). Most recent statistics in Portuguese territory confirm this scenario, with cardiovascular diseases killing about 11 persons per 100000 inhabitants. Reducing these numbers is urgent and requires early, quick and efficient diagnostic of the specific heart condition. Thus, the main goal of this proposal is to develop a low cost sensing-devices based on newly synthesized sensory biomaterials for screening cardiac bi-omarkers in point-of-care. These were applied to screen the conventional bi-omarkers of clinical interest, all peptides in nature. These include troponin T (TnT), creatine kinase isoenzyme (CK-MB) and myoglobin (Myo). This was achieved by means of novel and low cost biosensing materials that were designed to display good selectivity to each biomarker, assembled on nanostructured sens-ing units and tested on serum samples. The design of novel biosensing materials consisted on synthesizing plastic antibodies by means of novel molecular im-printing (MI) and enzymatic approaches. Nanostructured sensing units were as-sembled by modifying the surface of standard conductive materials with the pre-viously indicated biomaterials. Standard conductive supports selected for this purpose were carbon and gold. Overall, it is expected that the emerging biosensing materials and platforms out coming from this project may contribute for the development of new non-inva-sive or minimally invasive methods with clinical application in the early screen-ing of chronic diseases and fast-screening in point-of-care (POC) of acute events.