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Herein, a conjugated conducting polymer-based impedimetric aptasensor has been developed to detect beta-human chorionic gonadotropin (bHCG), the one of the important biomarkers in gynecology, from synthetic human urine samples. In this context, gold electrodes were, firstly coated with pyrrole and pyrrole-3-carboxylic acid to obtain the poly(pyrrole-pyrrole-3-carboxylic acid) [poly(Py-PyCOOH)] conductive copolymer by cyclic voltammetry (CV). Then, bHCG-specific peptide aptamer was covalently linked onto the surface via applying a well-known carbodiimide-succinimide chemistry. The sensor developed was characterized to confirm modification steps via both electrochemical methods including CV, electrochemical impedance spectroscopy (EIS), and chronoamperometry and physico-chemically via attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), atomic force microscope (AFM), and contact angle measurements (CA). The analytical performance of the sensor was evaluated in the concentration range from 1 μg/mL to 100 μg/mL for successful detection of bHCG even in the presence of interference agents. The results have also revealed that the sensor could be classified as a promising alternative to its benchmark commercial clinical methods due its superior properties such as cost-friendliness, easy-to-prepare, stable, robust, and selectivity / sensitivity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

This study is the first successful application of a nanomaterial-supported molecularly imprinted polymer (MIP)-based electrochemical sensor for the sensitive and selective determination of apigenin (API), which is a naturally occurring product of the flavone class that is an aglycone of several glycosides. Secondary metabolites are biologically active substances produced by plants in response to various environmental factors. The levels of these compounds can vary depending on factors such as climate, soil conditions and the season in which the plants are grown. Therefore, the analysis of these compounds is essential to properly understand the biological effects of plant extracts and to ensure their safe use. To increase the glassy carbon electrode (GCE) surface's active surface area and porosity, zinc oxide nanoparticles (ZnO NPs) were integrated into the MIP-based electrochemical sensor design. Tryptophan methacrylate (TrpMA) was selected as the functional monomer along with other MIP components such as 2-hydroxyethyl methacrylate (HEMA, basic monomer), 2-hydroxy-2-methylpropiophenone (initiator), and ethylene glycol dimethacrylate (EGDMA, crosslinking agent). The morphological and electrochemical characterizations of the developed API/ZnO NPs/TrpMA@MIP-GCE sensor were performed with scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The indirect measurement approach via 5.0 mM [Fe(CN) 6 ] 3-/4- solution was utilized to determine API in the linear range of 1.0x10 -13  M - 1.0x10 -12  M. The limit of detection (LOD) and limit of quantification (LOQ) for standard solutions were found to be 2.47x10 -14 and 8.23x10 -14  M, respectively. In addition, the extraction processes were carried out using ultrasound-assisted extraction (UAE) and maceration (MCR) procedures. For Apium graveolens L., Petroselinum crispum (Mill.) Fuss and herbal supplement, the API recoveries varied from 98.79 % to 102.71 %, with average relative standard deviations (RSD) less than 2.25 % in all three cases. The sensor's successful performance in the presence of components with chemical structures similar to the API was also demonstrated, revealing its unique selectivity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Herein, we proposed a new approach to design a MIP-based electrochemical sensor with carbon nanofiber (CNF), which could improve its conductivities as well as electrode sensitivity and successful detection of dasatinib (DAS). CNFs are capable of forming high porosity with significant interconnected porous networks. The poly(2-hydroxyethyl-methacrylate-N-methacryloyl-L-tyrosine) (PHEMA-MATyr) copolymer was synthesized in the presence of both CNF and DAS by photopolymerization. After optimization of the parameters, the modified MIP-based electrochemical sensor demonstrated the ability to determine the DAS in the linear working range of 1.0 × 10 -14 -1.0 × 10 -13 M for the standard solution and commercial serum samples with a LOD of 1.76 × 10 -15 and 2.46 × 10 -15 , respectively. Good linearity for DAS was observed with correlation coefficients (r) of 0.996 and 0.997 for the standard solution and commercial serum samples, respectively. The recoveries of the DAS ranged from 99.45 % to 99.53 % for the tablet dosage form and commercial serum samples, with average relative standard deviations below 1.96 % in both cases. The proposed modified sensor demonstrated significant sensitivity and selectivity for the rapid determination of DAS in commercial serum samples and tablet form., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this study, an electrochemical chemosensor that utilizes a conductive polymer-based molecularly imprinted polymer (MIP) surface for rapid and reliable determination of CA125 was devised. A novel method has been applied to fabricate CA125 imprinted polypyrrole nanotubes (MI-PPy NT) via vapor deposition polymerization (VDP) as a recognition element for highly selective and sensitive determination of CA125. The chemosensor was prepared by immobilizing MI-PPy NT onto screen-printed gold electrodes (Au-SPE) and the performance of the sensor was evaluated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in terms of selectivity, sensitivity, linear dynamic concentration range (LDR) and limit of detection (LOD). The MI-PPy NT@Au-SPE sensor exhibited high sensitivity (68.57 μA per decade) to the CA125 concentration ranging from 0.1 U mL -1 to 100 U mL -1 at an LOD of 0.4 U mL -1 with a correlation coefficient of 0.9922. The developed chemosensors with their novel design combined with a facile fabrication method, prove to be promising as future state-of-the-art biosensors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Quercetin (QUE) is a powerful antioxidant and one of the common phenolic compounds found in plants, vegetables, and fruits, which has shown many pharmacological activities. The complex nature of the matrix in which QUE is found and its importance and potential uses in diverse applications force the researchers to develop selective and sensitive sensors. In the present work, a novel molecularly imprinted polymer (MIP)-based electrochemical sensor was fabricated for the selective and sensitive determination of the QUE in plant extracts and food supplements. Tryptophan methacrylate (TrpMA) was chosen as the functional monomer, whereas the photopolymerization (PP) method was applied using a glassy carbon electrode (GCE). Electrochemical and morphological characterizations of the developed sensor (TrpMA@QUE/MIP-GCE) were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). The linear range of the developed sensor was determined to be in the range of 1.0-25 pM, while the limit of detection (LOD) was calculated to be 0.235 pM. In conclusion, The TrpMA@QUE/MIP-GCE sensor might be classified as a promising platform for selective and sensitive determination of QUE not only in plant extracts but also in commercial food supplements because of its reliability, reproducibility, repeatability, stability, and fast response time., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study represents nanoparticle-based well-oriented recognition sites via interface imprinting, followed by selective and sensitive determination of fluoxetine (FLX). Herein, FLX was firstly immobilized onto ZnO NPs, and then polymerization was carried out with MAPA, HEMA, and EGDMA on the glassy carbon electrode via photopolymerization. After the etching of ZnO with and 10 mM HCI solution, a porous structure with recognition sites for FLX was constructed onto surface. The characterization of the electrochemical sensor was accomplished by utilizing CV, EIS, ATR-FTIR AFM, and SEM analysis. The DPV was used to determine FLX in standard solution, serum sample, and tap water. The effect of FLX concentration variation was studied using the DPV in the range of 1.0 × 10 -11 M to 1.0 × 10 -10 M with a detection limit of 2.67 × 10 -12 M. This sensor showed specific recognition toward template, and more than 90% of its original response was retained after being stored in the desiccator at R.T. for 5 days. This technique has proven to be a powerful, highly selective, and sensitive tool for the rapid detection of FLX in tap water and spike serum samples., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The stamp markings on wooden surfaces, which are placed on trees and products including antiques, indicate the status of trees and involve identifying data regarding the products. Such markings are obliterated either to facilitate illegal logging or to conceal product information. Despite the wide literature on the restoration of obliterated characters on metal and polymer surfaces, the recovery of defaced characters on wooden surfaces appears to be understudied. Several reference texts in the forensic marks' examination literature suggest that water, water vapor, and alkaline solutions are useful in restoring the abraded markings on the wood. Since there does not seem to be any experimental study proving such success, this study aimed to fill this gap. This study conducted experimental research by using water, ethanol, ammonia, and chloroform to recover the scraped characters on samples obtained from walnut, beech, spruce, oak, and cedar trees. The cold-stamped characters, which were defaced at varying depths, were restored using vapor and liquid phases of four solvents. While the vapor phases of water, ethanol, and ammonia yielded good outcomes on all types of wooden surfaces, the liquid phases did not seem to be useful in the revisualization process. The response of the vapors, which varied between 62 and 220 s, depended on the type of wood. The restoration technique developed in this research offers the possibility of on-site usage, easy application, utilization of low-cost solvents, rapid recovery, and effectiveness on various wooden surfaces. Overall, the restoration methodology used in this research appears to be fruitful in retrieving identifying information on wooden samples., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.)

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., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In this work, pyrrole-histidine has been designed, synthesized and, used as a novel functional monomer to fabricate a molecularly imprinted electrochemical sensor for the selective and sensitive detection of teriflunomide (TER). The molecularly imprinted thin film of electrochemical sensor was constructed by directly electropolymerization of co-polymer of pyrrole-histidine (PyHis) with pyrrole in the presence of a template, TER, on a glassy carbon electrode (GCE). After electropolymerization, the structure and morphology of the fabricated MIP sensor were characterized by Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) and its electrochemical parameters such as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS). The poly (pyrrole-co-pyrrole-histidine) [Poly (Py-co-PyHis)]@MIP/GCE sensor have a linear TER concentration in the of 0.1-1.0 pM with a low detection limit of 11.38 fM. The present strategy for electrochemical sensor have been also showed excellent recovery in synthetic serum samples and tablet dosage form with the recoveries 97.56% and 100.35%, respectively. The developed [Poly (Py-co-PyHis)]@MIP/GCE sensor exhibited an excellent electrochemical response for TER due to the synergistic effect of conducting polymer and molecularly imprinting techniques., (Copyright © 2022 Elsevier B.V. All rights reserved.)

A novel methodology has been applied to generate a porous molecularly imprinted material for highly selective and sensitive recognition of Janus kinase inhibitor ruxolitinib (RUX). The porous material-based nucleobase-derivative functional monomer was developed by a photopolymerization method. The thymine methacrylate (ThyM) as a functional monomer was synthesized and copolymerized with 2-hydroxyethyl methacrylate (HEMA) in the presence of ethylene glycol dimethacrylate (EGDMA) onto the glassy carbon electrode [glassy carbon electrode/molecularly imprinted polymer@poly(2-hydroxyethyl methacrylate-co-thymine methacrylate), (GCE/MIP@PHEMA-ThyM)] for the first time. The presence of ThyM results in the functional groups in imprinting binding sites, while the presence of poly(vinyl alcohol) (PVA) allows to generate porous materials for sensitive sensing. The characterization of GCE/MIP@PHEMA-ThyM was investigated by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), and impedance spectroscopy technique. Then, the porous MIP modified glassy carbon electrode was optimized with effecting parameters including removal agent, removal time, and incubation time to get a better response for RUX. Under well-controlled optimum conditions, the GCE/MIP@PHEMA-ThyM linearly responded to the RUX concentration up to 0.01 pM at the limit of detection (LOD) of 0.00191 pM. The non-imprinted polymer (NIP) was also prepared to serve as a control in the same way but without the template. The proposed method improves the accessibility of binding sites by generating the porous material resulting in highly selective and sensitive recognition of drugs in the pharmaceutical dosage form and synthetic human serum samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Apoptosis is a type of cell death caused by the occurrence of both pathological and physiological conditions triggered by ligation of death receptors outside the cell or triggered by DNA damage and/or cytoskeleton disruption. Timely monitoring of apoptosis can effectively help early diagnosis of related diseases and continuous assessment of the effectiveness of drugs. Detecting caspases, a protease family closely related to cellular apoptosis, and its identification as markers of apoptosis is a popular procedure. Biosensors are used for early diagnosis and play a very important role in preventing disease progression in various body sections. Recently, there has been a widespread increase in the desire to use materials made of paper (e.g. nitrocellulose membrane) for Point-of-Care (POC) testing systems since paper and paper-like materials are cheap, abundant and degradable. Microfluidic paper-based analytical devices (μPADs) are highly promising as they are cost-effective, easy to use, fast, precise and sustainable over time and under different environmental conditions. In this review, we focused our efforts on compiling the different approaches on identifying apoptosis pathway while giving brief information about apoptosis and biosensors. This review includes recent advantages in biosensing techniques to simply determine what happened in the cell life and which direction it would continue. As a conclusion, we believed that the review may help to researchers to compare/update the knowledge about diagnosis of the apoptosis pathway while reminding the basic definitions about the apoptosis and biosensor technologies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

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 (R 2 = 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 (R 2 = 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., (Copyright © 2020 Elsevier B.V. All rights reserved.)

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 ( 1 H 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., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The continuous bed bioreactor systems have been used for the production of protein therapeutics, such as IgG, using immobilized enzyme in biopharmaceutical applications. We developed macroporous poly(hydroxyethyl methacrylate-co-glycidyl methacrylate) cryogel-based bioreactor matrix using sodium dodecyl sulfate as surfactans in the presence of ethylene glycol dimethacrylate as cross linking agent by bulk polymerization. The developed polyGMA immobilized bioreactor with papain enzyme was used for specific fragmentation of immunoglobulin G. The catalysis efficiency for immobilized enzyme were investigated in comparison with free enzyme. The immobilized papain displayed broad catalytic activity over a variety of conditions, with maximal activity around pH 7.0 and 70 °C. The Michaelis-Menten kinetic constant (K m ), the maximum reaction velocity (V max ), and the catalytic efficiency (k cat ) for free enzyme were 0.1097 mg/mL, 29.9 mg/mL/min, and 92.01 1/min, respectively, whereas for immobilized enzyme, K m , V max , and k cat values were 0.1078 mg/mL, 30.53 mg/mL/min, and 94.3 1/min, respectively. In a further step, after digestion, remarkable digestion products of bioreactor, Fab and Fc fragments, produced with immobilized papain bioreactors were analyzed in two ways by SDS-PAGE and reversed-phase HPLC; it was demonstrated that papain immobilized bioreactor successfully used for the digestion of human IgG with high activity. Therefore, the polyGMA cryogel immobilized with papain exhibited a very effective matrix for the bioreactor which can be considered as an alternative bioreactor matrix with great promise in biopharmaceutical applications., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Automated on-line two-dimensional high-performance liquid chromatography method (2D-HPLC) is proposed to determine Ochratoxin A (OTA) in food samples as an alternative to OTA immunoaffinity column (IAC). An on-line 2D-HPLC system is designed for the analysis of OTA using an affinity-based monolithic column in the first dimension and reversed-phase C18 column in the second dimension. Initially, optimal OTA separation efficiency is determined through traditional HPLC system consisting of a P(HEMAPA) monolithic column coupled with HPLC system. Secondly, after providing optimum conditions, OTA determination was investigated through the 2D-HPLC system. According to results, 2D-HPLC system showed good linearity in the range 0.5 to 20 ng/mL with limit of detection (LOD) and limit of quantification (LOQ) values of 21.2 pg/mL and 64.3 pg/mL, respectively. The P(HEMAPA)-4 monolithic column displayed good recovery of OTA ranging from 104.34% to 107.33%. Relative standard deviations (RSD) varied in the range 0.21% to 1.31% thus indicating the efficiency of P(HEMAPA)-4 monolithic column developed for OTA., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A sandwich-type nanostructured immunosensor based on carboxylated multi-walled carbon nanotube (CMWCNT)-embedded whiskered nanofibres (WNFs) was developed for detection of cardiac Troponin I (cTnI). WNFs were directly fabricated on glassy carbon electrodes (GCE) by removing the sacrificial component (polyethylene glycol, PEG) after electrospinning of polystyrene/CMWCNT/PEG nanocomposite nanofibres, and utilised as a transducer layer for enzyme-labeled amperometric immunoassay of cTnI. The whiskered segments of CMWCNTs were activated and utilised to immobilise anti-cTnT antibodies. It was observed that the anchored CMWCNTs within the nanofibres were suitably stabilised with excellent electrochemical repeatability. A sandwich-type immuno-complex was formed between cTnI and horseradish peroxidase-conjugated anti-cTnI (HRP-anti-cTnI). The amperometric responses of the immunosensor were studied using cyclic voltammetry (CV) through an enzymatic reaction between hydrogen peroxide and HRP conjugated to the secondary antibody. The nanostructured immunosensor delivered a wide detection range for cTnI from the clinical borderline for a normal person (0.5-2ngmL -1 ) to the concentration present in myocardial infarction patients (> 20ngmL -1 ), with a detection limit of ~ 0.04ngmL -1 . It also showed good reproducibility and repeatability for three different cTnI concentration (1, 10 and 25ngmL -1 ) with satisfactory relative standard deviations (RSD). Hence, the proposed nanostructured immunosensor shows potential for point-of-care testing., (Copyright © 2018 Elsevier B.V. All rights reserved.)

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., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In this study, cryogel-based molecularly imprinted composite cartridges were designed for the rapid, efficient, and selective preconcentration of benzo[a]pyrene (BaP) from water samples. First, a BaP-imprinted poly(2-hydroxyethyl methacrylate-N-methacryloyl-(L)-phenylalanine) composite cartridge was synthesized under semi-frozen conditions and characterized by scanning electron microscopy, elemental analysis, Fourier transform infrared spectroscopy, and swelling tests. After the optimization of preconcentration parameters, i.e., pH and initial BaP concentration, the selectivity and preconcentration efficiency, and reusability of these cartridges were also evaluated. In selectivity experiments, BaP imprinted composite cartridge exhibited binding capacities 3.09, 9.52, 8.87, and 8.77-fold higher than that of the non-imprinted composite cartridge in the presence of competitors, such as benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), indeno[1,2,3-cd]pyrene (IcdP), and 1-naphthol, respectively. The method detection limit (MDL), relative standard deviation (RSD) and preconcentration efficiency (PE) of the synthesized composite cartridge were calculated as 24.86μg/L, 1.60%, and 349.6%, respectively., (Copyright © 2016 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 (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., (Copyright © 2016 Elsevier B.V. All rights reserved.)

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 11.86mg/g. The cryogels might be reused at least five times without significant decrease in adsorption capacity., (Copyright © 2016 Elsevier B.V. All rights reserved.)

L-Lysine imprinted poly(2-hydroxyethyl methacrylate-co-N-methacryloyl-L-aspartic acid) [P(HEMA-co-MAAsp)] cryogels were synthesized and characterized with Fourier transform infrared spectroscopy, scanning electron microscopy, surface area measurements, swelling, and squeezing tests. Specific surface area for imprinted cryogel was 34.2m(2)/g while the value was 21.3m(2)/g for non-imprinted cryogel. IgG adsorption from aqueous solution was examined in continuous mode examining the factors effecting adsorption capacity such as pH, concentration, flow rate, temperature, ionic strength, and incubation time. 0.5M NaCl was used as desorption agent. The IgG adsorption capacity was determined as 55.1 mg/g for 1.0 mg/mL IgG original concentration at 25.0°C while pH and flow rate were 7.0 and 0.5 mL/min, respectively. When human serum was used as IgG source, the removal of 90.4% of crude IgG was attained for 1/20 diluted plasma sample. The imprinted cryogel was used in ten successive cycles without significant loss in adsorption capacity. The cryogel was determined to be 1.79 times more selective to IgG than albumin and 1.45 times more selective than hemoglobin. The adsorption behavior well suited to Langmuir isotherm and the kinetics followed pseudo-second-order model. Thermodynamic parameters ΔH°, ΔS° and ΔG° for this adsorption process were also calculated., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Immunoaffinity chromatography (IAC) is a kind of bioaffinity chromatography which used antibodies or antibody-related molecules as the stationary phase. IAC is used by many applications for analytical, clinical and diagnostic purposes, particularly preferring in analytical purposes on one-step separation and purification of target compounds. Moreover, immunoaffinity chromatography is used in antibody enrichment and separation of cells. IAC columns are usually applied in the antibody experiments due to powerful and selective binding of antibodies and/or their target antigens. Antigen or antibody molecules could be immobilized to the solid support. Therefore, target antibody or cell is purified. Specific bioligands can be immobilized directly on glycidyl based polymeric material with simple acid-base catalyst. In this study, polyglycidyl methacrylate based therefore cryogels were prepared and anti-insulin antibodies were immobilized on porous surface of cryogels. Swelling test, Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and scanning electron microscopy (SEM) were conducted to characterize cryogels developed. To optimize separation conditions, effects of pH, initial insulin concentration, flow rate, salt concentration, contact time and temperature on insulin adsorption capacity were examined. The results indicated that the immunoaffinity cryogel developed here could be classified as good alternative with prominent properties such as high reusability and cost-friendly adsorbent and would be one of the primary reports for immunoaffinity purification of insulin molecules in not only lab-scale but also for industrial purposes., (Copyright © 2015 Elsevier B.V. All rights reserved.)

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., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In this study, we developed quartz crystal microbalance (QCM) nanosensor for the real-time detection of tobramycin (TOB). Firstly, the modification of gold surface of QCM chip was performed by self-assembling monolayer formation of allyl mercaptane to introduce polymerizable double bonds on the chip surface. Then, TOB imprinted poly(2-hydroxyethyl methacrylate-methacryloylamidoglutamic acid) [p(HEMA-MAGA)] film was generated on the gold surface. The nonmodified and TOB-imprinted p(HEMA-MAGA) surfaces were characterized by using atomic force microscopy (AFM), Fourier transform infrared (FTIR) spectroscopy, ellipsometry and contact angle measurements. The proposed method was validated according to the ICH guideline. The linearity range and the detection limit (S/N=3) were obtained as 1.7×10(-11)-1.5×10(-10) M and 5.7×10(-12) M, respectively. The developed method was applied to pharmaceuticals, and food samples such as chicken egg white and milk extract for the determination of TOB. In addition, association kinetics analysis and isotherm models were applied to the data to explain the adsorption process that took place., (© 2013 Elsevier B.V. All rights reserved.)

Novel aspartic acid incorporated monolithic columns were prepared to efficiently affinity purify immunoglobulin G (IgG) from human plasma. The monolithic columns were synthesised in a stainless steel HPLC column (20 cm × 5 mm id) by in situ bulk polymerisation of N-methacryloyl-L-aspartic acid (MAAsp), a polymerisable derivative of L-aspartic acid, and 2-hydroxyethyl methacrylate (HEMA). Monolithic columns [poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-aspartic acid) (PHEMAsp)] were characterised by swelling studies, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The monolithic columns were used for IgG adsorption/desorption from aqueous solutions and human plasma. The IgG adsorption depended on the buffer type, and the maximum IgG adsorption from aqueous solution in phosphate buffer was 0.085 mg/g at pH 6.0. The monolithic columns allowed for one-step IgG purification with a negligible capacity decrease after ten adsorption-desorption cycles., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this study, we aimed to develop an alternative matrix able to deplete the albumin (Alb) and immunoglobulin G (IgG) from blood plasma simultaneously to prepare plasma samples for large-scale applications of blood-related proteomics. As a first step, nano-protein A nanoparticles (nanoProA) were prepared and characterized. Subsequently, cibacron blue F3GA (CB) was immobilized onto the nanoProA's to enhance their specific affinity for Alb molecules. Finally, both nanoparticles, specifically, nanoProA and CB-nanoProA, were separately embedded into cryogel structures to combine advantages of the nanoparticles with those of the cryogels. The protein adsorption was optimized using aqueous Alb and IgG solutions separately. Subsequently, competitive protein adsorption was performed using a protein mixture prepared with Alb and IgG adhering to their plasma protein ratios. Because of the CB-immobilization, the Alb depletion performance of the cryogels increased whereas the IgG depleting performance decreased. Using the nanoProA, embedded cryogel removed 99.3% of the IgG, while using the CB-nanoProA embedded cryogel removed 97.5% of the Alb content. The simultaneous depletion performances of the cryogels for Alb and IgG were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In this study, the monolithic cryogel-based adsorbents were classified as an alternative matrix to prepare plasma samples for proteomics applications at the preparative scale., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this study, we prepared surface plasmon resonance (SPR) sensor using the molecular imprinting technique for myoglobin detection in human serum. For this purpose, we synthesized myoglobin imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-l-tryptophan methyl ester) [poly(HEMA-MATrp)] nanofilm on the surface of SPR sensor. We also synthesized non-imprinted poly(HEMA-MATrp) nanofilm without myoglobin for the control experiments. The SPR sensor was characterized with contact angle measurements, atomic force microscopy, X-ray photoelectron spectroscopy, and ellipsometry. We investigated the effectiveness of the sensor using the SPR system. We evaluated the ability of SPR sensor to sense myoglobin with myoglobin solutions (pH7.4, phosphate buffer) in different concentration range and in the serum taken from a patient with acute myocardial infarction. We found that the Langmuir adsorption model was the most suitable for the sensor system. The detection limit was 87.6 ng/mL. In order to show the selectivity of the SPR sensor, we investigated the competitive detection of myoglobin, lysozyme, cytochrome c and bovine serum albumin. The results showed that the SPR sensor has high selectivity and sensitivity for myoglobin., (Copyright © 2013. Published by Elsevier B.V.)

In this work, Cibacron Blue F3GA (CB) modified pencil graphite electrodes (PGEs) were prepared and their affinities to bovine serum albumin were investigated. Preparation of the PGEs was performed using cyclic voltammetry (CV) and passive adsorption techniques. Improved electrochemical results were obtained with the PGEs prepared by CV technique compared to the PGEs prepared by passive adsorption technique. In order to obtain more sensitive results number of scans used in CV technique and the effect of concentration of CB were studied. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and electrochemical impedance spectroscopy (EIS) were used for the characterization of modified electrodes. The modified PGEs were then used for the electrochemical monitoring of affinity interaction between CB and bovine serum albumin. The effect of BSA concentration and interfering species (tryptophan, glucose and immunoglobulin G) on the response of the electrode were examined. The aim of this study was to prepare an easy, fast, stable and cheap modified electrode for the investigation of the well-known affinity of CB to serum albumin. The electrochemistry can provide alternative routes for dye-protein interaction instead of using classical time-consuming methods., (Copyright © 2013. Published by Elsevier B.V.)

Surface modification of support materials is crucial for improving their selectivities and biocompatibilities in bioaffinity applications. However, conventional modification techniques including chemical or physical conjugations mostly suffer from limitations of their multistep and complicated procedures, surface denaturations, batch-to-batch inconsistencies, and insufficient surface conjugations. In this study, we demonstrate a simple yet effective bioinspired approach for the surface modification of poly(2-hydroxyethyl methacrylate) [PHEMA] based bioaffinity adsorbents through oxidative polymerization of dopamine. The magnetic (mPHEMA) and non-magnetic (PHEMA) polymeric microbeads were fabricated by suspension polymerization technique. Surface modification of obtained microbeads was then carried out by using dopamine molecules under alkaline conditions. The polydopamine (PDOPA) coated microbeads were further employed as a bioaffinity absorbent targeted for immunoglobulin G (IgG) molecules. The effects of pH, temperature, protein concentration and ionic strength on the IgG adsorption process have been investigated. We found that PDOPA coated microbeads display dramatically higher IgG adsorption capacities when compared with their un-modified forms. Adsorption capacities also increased with increasing temperature. Monolayer Langmuir adsorption model can be thought more applicable for these adsorbent systems., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In this study, lanthanide ion complex incorporated molecularly imprinted fluorescent nanoparticles were synthesized. A combination of three novel approaches was applied for the purpose. First, lanthanide ions [Terbium(III)] were complexed with N-methacryloyl-L-histidine (MAH), polymerizable derivative of L-histidine amino acid, in order to incorporate the complex directly into the polymeric backbone. At the second stage, L-histidine molecules imprinted nanoparticles were utilized instead of whole protein imprinting in order to avoid whole drawbacks such as fragility, complexity, denaturation tendency, and conformation dependency. At the third stage following the first two steps mentioned above, imprinted L-histidine was coordinated with cupric ions [Cu(II)] to conduct the study under mild conditions. Then, molecularly imprinted fluorescent nanoparticles synthesized were used for L-histidine adsorption from aqueous solution to optimize conditions for adsorption and fluorimetric detection. Finally, usability of nanoparticles was investigated for chiral biorecognition using stereoisomer, D-histidine, racemic mixture, D,L-histidine, proteins with surface L-histidine residue, lysozyme, cytochrome C, or without ribonuclease A. The results revealed that the proposed polymerization strategy could make significant contribution to the solution of chronic problems of fluorescent component introduction into polymers. Additionally, the fluorescent nanoparticles reported here could be used for selective separation and fluorescent monitoring purposes., (Copyright © 2013 Elsevier B.V. All rights reserved.)

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 21.4 m(2)/g for P(HEMA)-FD, 17.65 m(2)/g for P(HEMA-MAPA) and 36.0 m(2)/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 45.31 mg DNA/g, 27.08 mg DNA/g and 1.81 mg 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 © 2012 Elsevier B.V. All rights reserved.)

A miniaturized solid phase extraction procedure has been developed for ultra-trace determination of inorganic arsenic species. Arsenic(III) as pyrrolidinedithiocarbamate complex was selectively adsorbed on 30 mg poly(hydroxyethyl methacrylate) (PHEMA) micro beads, which is simply packed into a micro-pipette-tip. The adsorbed arsenic was quantitatively eluted by 700 μL 0.25 M NH(3) and determined by graphite furnace atomic absorption spectrometry (GFAAS). Injection of larger volume (i.e., 50 μL v.s. conventional 10-20 μL) eluent into graphite furnace and the use of Mg(NO(3))(2) as chemical modifier have improved atomic absorption signal intensity (sensitivity as characteristic mass of 25 pg) and precision (RSD of 2.6%, c=10 μg L(-1), n=11). Total arsenic amount was determined after reduction of arsenic(V) to arsenic(III) by thiourea-HCl system. As(V) concentration was calculated by the difference between As(III) and total arsenic. The detection limit (3s) of the method was found as 10 ng L(-1) As(III) with an enrichment factor of 86. The relative standard deviation and relative error for six replicate determinations of 0.5 μg L(-1) As(III) were found to be 4.0% and -0.7%, respectively. The method was successfully applied to drinking water, snow and reference water (SEM-2011) samples. When the samples were spiked with 0.5 and 1.0 μg L(-1) As(III) and As(V), the recoveries varied between 96 and 100%., (Copyright © 2012 Elsevier B.V. All rights reserved.)

In this study, we have focused our attention on preparing supermacroporous cryogels as a potential dye-affinity adsorbent for interferon purification. For this purpose, 2-hydroxyethyl methacrylate (HEMA) and Cibacron Blue F3GA (CB) were selected as main monomer and dye-ligand. Cibacron Blue F3GA attached supermacroporous poly(2-hydroxyethyl methacrylate) [poly(HEMA)/CB] cryogels were prepared and characterized by swelling test, scanning electron microscopy, elemental analysis, and FTIR. After that, the effecting factors such as pH, concentration, interaction time, and ionic strength on the interferon separation were evaluated. The maximum adsorption capacity of poly(HEMA)/CB cryogels was obtained as 38.2mg/g at pH 6.0. Fast protein liquid chromatography (FPLC) system was used for interferon purification from human gingival fibroblast extract. The chromatography parameters, capacity and selectivity factors, resolution and theoretical plate number were found as 7.79, 9.62, 4.23 and 554, respectively. Although some decreases in total protein content, from 320 μg to 18 μg, and interferon activity, from 2.6 × 10(3)IU to 2.2 × 10(3)IU, were determined, specific antiviral activity increased from 7.19 IU/μg to 122.2 IU/μg. The purified interferon samples have 97.6% purity determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After repeated ten adsorption-desorption cycles, no significant decrease was determined in adsorption capacity of cryogel. In result, poly(HEMA)/CB cryogels have an application potential for rapid, cheap and specific purification of interferon., (Copyright © 2012 Elsevier B.V. All rights reserved.)

In the present study, we have focused our attention to prepare molecular imprinted composite cryogel membranes for purification of hepatitis B surface antibody (anti-HBs) by fast protein liquid chromatography. Before the preparation of the molecular imprinted composite cryogel membranes (MI-CMs) by free radical polymerization at sub-zero temperature, we have synthesized and characterized the anti-HBs imprinted particles. Then, the cryogel membranes (CMs) were characterized by swelling test, scanning electron microscopy and Fourier transform infrared spectroscopy. Prior to chromatographic purification studies, the effective parameters on the anti-HBs adsorption process were evaluated by investigating the dependency of the adsorption capacity on flow-rate, anti-HBs concentration, contact time and ionic strength. The maximum anti-HBs adsorption capacity was calculated as 701.4 mIU/g CM. The selectivity of the MI-CMs was shown by competitive adsorption of anti-HBs, total anti-hepatitis A antibody (anti-HAV) and total immunoglobulin E (IgE) adsorption studies. The MI-CMs have relative selectivity coefficients as 5.45 for anti-HBs/total anti-HAV and 9.05 for anti-HBs/total IgE, respectively. The phosphate buffer solution (pH 7.4) containing 1.0M NaCl was used for elution, almost completely, of adsorbed anti-HBs molecules. The MI-CMs could be used many times without any significant decrease in the adsorption capacity. The chromatographic purification performances of the MI-CMs were also investigated. The chromatographic parameters such as capacity and separation factors, the theoretical plate number and resolution of the MI-CMs were calculated as 5.48, 6.02, 1153.9, and 1.72 for anti-HBs molecules, respectively. As a conclusion, we can say that the MI-CMs could be used for specific purification of anti-HBs from anti-HBs positive human plasma., (Copyright © 2012 Elsevier B.V. All rights reserved.)

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 2-3 μm, was estimated as 55.3 μmol MAH/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 24.7 mg insulin/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 (0.61 mg insulin/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 © 2011 Elsevier B.V. All rights reserved.)

The preparation of polymeric membrane using affinity technology for application in blood filtration devices is described here. DNA attached poly(hydroxyethyl methacrylate) (PHEMA) based microporous affinity membrane was prepared for selective removal of anti-dsDNA antibodies from systemic lupus erythematosus (SLE) patient plasma in in vitro. In order to further increase blood-compatibility of affinity membrane, aminoacid based comonomer N-methacryloyl-L-alanine (MAAL) was included in the polymerization recipe. PHEMAAL membrane was produced by a photopolymerization technique and then characterized by swelling tests and scanning electron microscope (SEM) studies. Blood-compatibility tests were also performed. The water swelling ratio of PHEMAAL membrane increased significantly (133.2%) compared with PHEMA (58%). PHEMAAL membrane has large pores around in the range of 5-10 microm. All the clotting times increased when compared with PHEMA membrane. Loss of platelets and leukocytes was very low. DNA loading was 7.8 mg/g. There was a very low anti-dsDNA-antibody adsorption onto the plain PHEMAAL membrane, about 78 IU/g. The PHEMAAL-DNA membrane adsorbed anti-dsDNA-antibody in the range of 10-68 x 10(3)IU/g from SLE plasma. Anti-dsDNA-antibody concentration decreased significantly from 875 to 144 IU/ml with the time. Anti-dsDNA-antibodies could be repeatedly adsorbed and eluted without noticeable loss in the anti-dsDNA-antibody adsorption amount., ((c) 2010 Elsevier B.V. All rights reserved.)

Hepatitis B surface antibody imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-L-tyrosine methyl ester) particles were prepared for the purification of hepatitis B surface antibody from human plasma. N-methacryloyl-L-tyrosine methyl ester was chosen as a complexing agent for hepatitis B surface antibodies. Hepatitis B surface antibody imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-L-tyrosine methyl ester) particles were characterized by surface area measurements, swelling test, scanning electron microscopy, elemental analysis, and Fourier transform infrared spectroscopy. Ethylene glycol (1.0M) was used as desorption agent. Adsorption studies were performed from hepatitis B surface antibody and anti-hepatitis A antibody positive human plasma. Effects of antibody concentration, contact time, N-methacryloyl-L-tyrosine methyl ester content and temperature on the adsorption capacity were investigated. The amount of hepatitis B surface antibody adsorbed per unit mass increased with increasing hepatitis B surface antibody concentration, then reached saturation. Maximum hepatitis B surface antibody adsorption amount was 21.4 mIU/mg. Adsorption process reached the equilibrium in 60 min. Competitive adsorption of hepatitis B surface antibody, total anti-hepatitis A antibody and total immunoglobulin E was investigated for showing the selectivity. Hepatitis B surface antibody-imprinted particles could adsorb hepatitis B surface antibody 18.3 times more than anti-hepatitis A antibody and 2.2 times more than immunoglobulin E. It can be concluded that hepatitis B surface antibody-imprinted particles have significant selectivity for hepatitis B surface antibody.

Study Objective: To determine the effect of dexmedetomidine on intraoperative bleeding during septoplasty and tympanoplasty operations., Design: Randomized, placebo-controlled study., Setting: Univesity medical center., Patients: 80 ASA physical status I and II patients, aged 18 to 65 years, 40 of whom were scheduled for septoplasty and 40 to undergo tympanoplasty operations., Interventions: Patients undergoing septoplasty (S) and tympanoplasty (T) operations were randomly divided into 4 groups. Dexmedetomidine (D) was administered to Group SD and Group TD first as a bolus dose of one microg kg(-1), then intraoperative maintenance was supplied with dexmedetomidine 0.7 microg kg(-1) hour(-1). Groups S and T (controls) were given identical amounts of saline. If systolic blood pressure measurements are greater than 20% preoperative values, then fentanyl one microg kg(-1) was given., Measurements: Intraoperative blood loss was determined with suction volumes and gauze counting. Bleeding was rated according to a 6-point scale. Hemodynamic parameters and fentanyl administration were recorded., Main Results: Group SD had less bleeding and lower bleeding scores (P < 0.05). In addition, this group received less intraoperative fentanyl (P < 0.05). The only significant difference between Groups TD and T was the amount of intraoperative fentanyl given (35.4 +/- 58.8 vs 110.0 +/- 81.0 microg) (P < 0.05)., Conclusion: Dexmedetomidine reduces bleeding, bleeding scores, and intraoperative fentanyl consumption during general anesthesia in septoplasty operations.

Magnetic poly(2-hydroxyethyl methacrylate) mPHEMA beads carrying Cibacron Blue F3GA were prepared by suspension polymerization of HEMA in the presence of Fe3O4 nano-powder. Average size of spherical beads was 80-120 microm. The beads had a specific surface area of 56.0m(2)/g. The characteristic functional groups of dye-attached mPHEMA beads were analyzed by Fourier transform infrared spectrometer (FTIR) and Raman spectrometer. mPHEMA with a swelling ratio of 68% and carrying 28.5 micromol CibacronBlueF3GA/g were used for the purification of lysozyme. Adsorption studies were performed under different conditions in a magnetically stabilized fluidized bed (i.e., pH, protein concentration, flow-rate, temperature, and ionic strength). Lysozyme adsorption capacity of mPHEMA and mPHEMA/Cibacron Blue F3GA beads were 0.8 mg/g and 342 mg/g, respectively. It was observed that after 20 adsorption-desorption cycle, mPHEMA beads can be used without significant loss in lysozyme adsorption capacity. Purification of lysozyme from egg white was also investigated. Purification of lysozyme was monitored by determining the lysozyme activity using Micrococcus lysodeikticus as substrate. The purity of the desorbed lysozyme was about 87.4% with recovery about 79.6%. The specific activity of the desorbed lysozyme was high as 41.586 U/mg.

Poly(ethylene glycol dimethacrylate-n-vinyl imidazole) [poly(EGDMA-VIM)] hydrogel (average diameter 150-200 microm) was prepared by copolymerizing ethylene glycol dimethacrylate (EGDMA) with n-vinyl imidazole (VIM). The copolymer hydrogel bead composition was characterized by elemental analysis and found to contain 5 EGDMA monomer units each VIM monomer unit. Poly(EGDMA-VIM) beads had a specific surface area of 59.8 m2/g. Poly(EGDMA-VIM) beads were characterized by swelling studies and scanning electron microscopy (SEM). These poly(EGDMA-VIM) beads with a swelling ratio of 78% were used for the heavy metal removal studies. Chelation capacity of the beads for the selected metal ions, i.e., Cd(II), Hg(II) and Pb(II) were investigated in aqueous media containing different amounts of these ions (10-750 mg/l) and at different pH values (3.0-7.0). Chelation rate was very fast. The maximum chelation capacities of the poly(EGDMA-VIM) beads were 69.4 mg/g for Cd(II), 114.8 mg/g for Pb(II) and 163.5 mg/g for Hg(II). The affinity order on molar basis was observed as follows: Hg(II) > Cd(II) > Pb(II). Chelation behavior of heavy metal ions could be modelled using both the Langmuir and Freundlich isotherms. pH significantly affected the chelation capacity of VIM incorporated beads. Chelation of heavy metal ions from synthetic wastewater was also studied. The chelation capacities are 45.6 mg/g for Cd(II), 74.2 mg/g for Hg(II) and 92.5 mg/g for Pb(II) at 0.5 mmol/l initial metal concentration. Regeneration of the chelating-beads was easily performed with 0.1 M HNO3. These features make poly(EGDMA-VIM) beads potential candidate adsorbent for heavy metal removal., (Copyright 2003 Elsevier B.V.)