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Gelatin and N-methacryloyl-(L)-histidine methyl ester [MAH] containing poly(2-hydroxyethyl methacrylate) [PHEMA] based cryogels were prepared to aid in enhancing cell proliferation. In order to evaluate effects of MAH comonomer and gelatin, cryogels were prepared containing different amounts of gelatin and MAH. Accordingly, four different groups of cryogels which were PHEMA, poly(2-hydroxyethyl methacrylate)-gelatin [PHEMA/GEL], poly(2-hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methyl ester) [PHEMAH] and poly(2-hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methyl ester)-gelatin [PHEMAH/GEL] were prepared and a total of eight cryogel groups were obtained depending on the varying gelatin ratios. Swelling tests, scanning electron microscope (SEM), microcomputed tomography (Micro-CT) and Fourier transform infrared spectroscopy- Attenuated Total Reflectance (FTIR-ATR) were performed for characterization studies. FTIR-ATR studies confirmed that gelatin and MAH were incorporated into the cryogel structures. Average pore size of cryogels was in the range of 18−198 μm confirmed by Micro-CT and SEM analysis. Then, cryogels were evaluated for cell proliferation abilities by MTT analysis for 24 h and 48 h for cell viability in L929 mouse fibroblast cells. Cell viability of PHEMAH/0.2GEL cryogels reached 209 %. Interaction and proliferation of fibroblast cells on cryogels demonstrated by SEM examination.

Iron (Fe) is an essential mineral, but iron overload can reason in multiple organ failures and cell injury. Iron overload syndromes can be widely classified as hereditary hemochromatosis. The development of iron overload is seen in hereditary hemochromatosis, a common inherited disorder that may lead to progressive organ dysfunction including cirrhosis, arthritis, hypogonadism, diabetes mellitus, and cardiomyopathy. If patients with iron overload are not treated, their life expectancy will be shortened. Nanochelators are usually utilized to remove overload iron. Many novel nanochelator have been formulated for effective methods. The ion molecular imprinting is a technique to form recognition sites in the highly cross-linked polymer using a template ion. In this research, effective ion-imprinted polymer-based nanoparticles were synthesized and evaluated for selective removal of iron(III). The iron-imprinted nanoparticles were prepared by using functional monomer N-methacryloyl-l-glutamic acid (MAGA) and comonomer 2-hydroxyethyl methacrylate by mini-emulsion polymerization techniques. The template analyte was desorbed with 0.01 M EDTA desorption agent. The iron-imprinted nanoparticles were selective for Fe(III) toward other analogs (Zn(II), Cr(III) and Al(III)). The adsorption isotherm model fitted the Langmuir isotherm with 0.995 of R2 value and the 83.33 mg/g of Qmax value for the Fe(III)-imprinted nanoparticles. The values of separation factor (RL) were found to be 0.016 for Fe(III). The maximum binding capacity for the ion-imprinted nanoparticles was found to be 77.80 mg/g dry nanoparticles, which is 8.9 times higher than the non-imprinted nanoparticles under the same conditions. Synthetic gastric fluid experiments were also performed for Fe(III) removal.

In this study, we fabricated magnetic ion-imprinted polymers (IIP) for arsenic removal. Ion-imprinted method was developed by complexing N-methacryloyl-l-cysteine (MAC) monomer and As(III) and As(V...

In this study, a selective, rapid and sensitive surface plasmon resonance (SPR) sensor is prepared for real time detection of tartrazine in fruit juice. Tartrazine imprinted and non-imprinted poly(hydroxyethylmethacrylate-N-methacryloyl-(L)-histidine methyl ester) thin films are synthesized onto SPR chip surface using ultraviolet polymerization. The characterization studies of tartrazine imprinted and non-imprinted SPR sensors are performed with contact angle measurements, atomic force microscopy and ellipsometry. Then, kinetic studies for tartrazine are carried out in the concentration range of 0.5–100.0 $\mu \text{M}$ . The response time for adsorption, desorption and regeneration cycles is approximately about 15 min for the optical sensor system. The limit of detection and quantification are obtained as $0.0076~\mu \text{M}$ and $0.0252~\mu \text{M}$ , respectively. The selectivity studies of the tartrazine imprinted and non-imprinted SPR sensors are determined in the presence of allura red and sunset yellow molecules. In order to demonstrate the applicability, validation studies of tartrazine imprinted SPR sensor are performed by liquid chromatography-tandem mass spectrometry (LC-MS).

Ochratoxin A (OTA), a group of highly toxic fungal secondary metabolites, is one of the most common mycotoxins that contaminate a wide range of agricultural products. Herein, we designed a label-free and selective surface plasmon resonance (SPR) based sensor for detection of OTA contamination in dried fig. The molecularly imprinted polymer film (MIP) was fabricated onto the SPR sensor chip by using light-initiated polymerization of N-methacryloyl-(L)-phenylalanine and 2-Hydroxyethyl methacrylate in the presence of OTA as a template. SPR chips were characterized by using contact angle, atomic force microscopy, and ellipsometry. OTA imprinted sensor was displayed a broad linear range, between 0.1 ng/mL and 20 ng/mL. The limit of detection was calculated as 0.028 ng/mL. The selectivity studies of the OTA imprinted SPR sensor was performed in the presence of aflatoxin M1, aflatoxin B1, and citrinin. The imprinting factor was found to be 2.85. The adsorption behavior of the OTA imprinted sensor was found as suitable for the Langmuir model. Results displayed that the OTA imprinted SPR sensor was successfully applied to determine OTA in dried fig samples.

Applications of nanomaterials to biological systems have received increased interest in the past decades. In particular, bacterial cellulose nanofibers can be utilized in a broad range of applications. Biomaterials have been produced on large-scale with high reproducibility by an inspiring method such as molecular imprinting. Herein, for the first time, magnetic bacterial cellulose nanofibers are designed by the molecular imprinting method as a novel adsorbent for selective and efficient recognition of thymidine nucleoside. In this process, magnetic bacterial cellulose nanofibers are silanized with 3-(trimethoxysilyl) propyl methacrylate and further polymerized with a hydrophilic monomer for templating thymidine via metal chelate coordination. They are characterized by several methods and then applied for thymidine recognition to optimize the adsorption conditions. Hereby, the effecting factors are evaluated, and the highest adsorption capacity is obtained as 431.3 mg/g in pH 9.0 at 25 °C. The selectivity is assessed with competitor nucleosides and highly selective (4.13 and 3.80 times) adsorption of thymidine at the same concentration of other nucleosides (cytidine and uridine) is observed. After multiple adsorption–desorption experiments, the magnetic bacterial cellulose nanofibers also provided high reusability capacity. The present new work holds excellent potential for nucleoside recognition by integrating molecular imprinting with magnetic bacterial cellulose nanofibers.

Atrazine-imprinted reduced graphene oxide composite with its enhanced functionalities and porous surface was successfully synthesized and applied for the selective determination of atrazine in complex matrices. Scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction studies revealed the imprinted polypyrrole beads formation on the reduced graphene oxide lining. Resultant composite was used to modify screen-printed electrode which then showed improved properties for voltammetric determination of atrazine. Measurements were carried out via square wave voltammetry giving a peak at − 0.9 V corresponding to the reduction of atrazine heterocyclic moiety. Obtained LOD and LOQ for atrazine were found to be 0.4 nmol/dm3 and 1.2 nmol/dm3, respectively, at optimized parameters. The method was applied for the atrazine determination in complex aqueous matrices.

In the present study, the enantiomeric forms of hydrophobic amino acids ( l -tryptophan, l -tyrosine, and l -phenylalanine) were separated by molecularly imprinted capillary columns (MICC) via Capillary Electrochromatography (CEC) for the first time. The monomer ratio, crosslinker ratio, template molecule ratio, the porogen ratio and type, polymerization time, and also the effect of temperature were examined to increase the permeability properties of MICC. FTIR, SEM and BET analyses were realized for the characterization of MICC. The effect of the electric field, organic solvent ratio, and pressure were carried out experimentally to determine the optimum conditions. The separation performances of MICC and the non-imprinted capillary columns (NICC) were compared electrochromatographically.

Nucleic acid aptamers are an emerging class of artificial ligands and have recently gained attention in several areas. Here we report the design of a surface plasmon resonance (SPR) aptasensor for highly sensitive and selective sensing of human activated protein C (APC). First, DNA aptamer (DNA-Apt) specific for APC is complexed with N-methacryloyl-L-cysteine (MAC) monomer. Then, 2-hydroxyethyl methacrylate (HEMA) and cyanamide are mixed with the DNA-Apt/MAC complex. The SPR aptasensor is characterized by atomic force microscopy, ellipsometry, and contact angle measurements. Selectivity of SPR aptasensor is carried out in the presence of myoglobin (Myb), hemoglobin (Hb), and bovine serum albumin (BSA). Limit of detection (LOD) and limit of quantification (LOQ) values are 1.5 ng mL?1 and 5.2 ng mL?1, respectively. DNA-Apt SPR aptasensor performance for APC detection is also examined in artificial plasma. © 2022, Springer Science+Business Media, LLC, part of Springer Nature.

Hemoglobin (Hb) is the most abundant protein in the blood. It is vital for the living as oxygen carriers. Some of the very pure Hb-containing biological fluids are currently under clinical trial. However, the removal and purification of Hb from the blood are quite difficult, especially when it is at a low concentration level. In this study, the molecularly imprinted polymeric nanoparticles (MIPNs) were prepared using N-methacryloyl-histidine methyl ester (MAH) by mini-emulsion polymerization technique for specific binding of human hemoglobin (HHb). MIPNs in monosize form have a size of 152 +/- 4 nm. They also have a high binding capacity (32.33 mg/g) of HHb. MIPNs retain 84% of the re-binding capacity for HHb after 10 cycles. The nanoparticles have 16 and 5 times higher binding capacity of HHb, respectively, in the presence of bovine serum albumin and lysozyme. Thanks to their high binding capacity and selectivity, MIPNs will allow them to be detected selectively for different target molecules. According to molecular docking, the main binding forces depend on hydrogen bonds and Van der Waals forces in the interaction within 5 angstrom around MAH molecule are observed through the amino acid residues of HHb at beta 1 and beta 2 subunit. The statistical mechanical analysis of docking showed that the free energy (Delta G) is -2732.14 kcal/mol, which indicates the interaction between MAH and HHb is energetically favorable at 298.15 degrees K.

Cibacron blue F3GA functionalized poly(hydroxyethyl methacrylate) cryogel membranes were prepared and applied for a simple purification of malate dehydrogenase (MDH) from crude extract of S...

Immunoaffinity chromatography has a huge interest in the biomedical and biotechnological fields, in particular for one-step isolation, purification and removal of analyte compounds. In this study, uniform-sized microcryogels, a new type of cryogels, were synthesized using 2-hydroxyetyhl methacrylate and epoxy-group-containing monomer, glycidyl methacrylate for purification of a plasma protein, transferrin. Immunoaffinity microcryogels containing anti-Tf antibodies were characterized by Raman spectroscopy, Fourier transform infrared spectroscopy, optical microscopy, scanning electron microscopy, density measurements and swelling tests. Adsorption studies in aqueous media were carried out in order to examine the effects of medium pH, initial concentration of analyte and contact time. It was found that the optimum pH was 6.0 and the maximum adsorption capacity of immunoaffinity microcryogels at this pH value found to be 9.82 mg/g. The KL constant for Langmuir isotherm was calculated as 2.65 mL/mg. The maximum adsorption capacity obtained from experimental studies is also very close to the calculated Langmuir adsorption capacity (11.27 mg/g). Langmuir adsorption isotherms and pseudo-second-order kinetic models are consistent with the adsorption process, which means that the adsorption is single layered and chemically controlled. The purity of the eluted hsTf from plasma was about 84% with yield about 82%. After the tenth use of the same microcryogels, the maximum hsTf adsorption capacity decreased by about 20%. The results indicated that the immunoaffinity microcryogels having anti-Tf antibody ligands could be a safe and cost-friendly method for purification of transferrin.

It was aimed to prepare immunoglobulin G (IgG) imprinted thermosensitive p(NIPA-MAH)/IgG-MIP monolithic cryogel for IgG purification. NIPA and MAH was selected as functional comonomers in order to synthesis of thermosensitive IgG imprinted polymer. NIPA is a thermo-responsive monomer with a LCST of 32 °C. It has a hydrophobic character above LCST and hydrophilic character below LCST. MAH provides selective binding on/in the IgG imprinted cavities with the advantage of its ionizable groups depending on change of pH value. After characterization studies, IgG binding capacity of the p(NIPA-MAH) cryogel from aqueous solutions was examined in different experimental conditions. Maximum IgG binding capacity was 106.1 mg/g, obtained at pH 7.4 and 40 °C. The p(NIPA-MAH)/IgG-MIP cryogel was reusable at least ten times. Selectivity of the p(NIPA-MAH) cryogel for IgG was investigated and suitability of the imprinted cryogel for IgG purification from human plasma was confirmed. In conclusion, the resultant cryogel having increased porosity along with high mechanical and chemical strength could meet requirements; thereby these properties make the p(NIPA-MAH)/IgG-MIP cryogel suitable gel matrix for IgG purification. The p(NIPA-MAH)/IgG-MIP cryogel serving as a thermosensitive molecularly imprinted polymer offers high potential for selective recognition of IgG via imprinting and controlled binding-elution opportunity by simple thermoresponsive regulation.

In this study, quartz crystal microbalance sensors based on molecular imprinting technology were fabricated for real-time detection of insulin in aqueous solution and artificial plasma. This study describes the preparation of insulin imprinted poly(hydroxyethyl methacrylate)-N-methacryloyl-( l )-histidine methyl ester based quartz crystal microbalance sensor for insulin determination. Poly(hydroxyethyl methacrylate)-N-methacryloyl-( l )-histidine methyl ester based film on chip surface was synthesized by ultra violet (UV) polymerization for the detection of insulin at low concentrations. At the first step, N-methacryloyl-( l )-histidine methyl ester complex was formed with insulin and then, the insulin imprinted film has been prepared. The characterization of the polymeric film has been conducted with ellipsometry, contact angle, Fourier transform infrared-attenuated total reflectance and atomic force microscopy measurements. Langmuir, Freundlich and Langmuir-Freundlich adsorption isotherm models were applied for this system. The best fitted model to explain the interactions between molecular imprinted chip and insulin molecules was the Langmuir adsorption isotherm (R2: 0.999). The repeatability of insulin imprinted chip was investigated by using of equilibration-binding-regeneration cycles for four times. The detection limit was found as 0.00158 ng/mL. According to the results, the QCM sensor has showed low-detection limit, high selectivity and sensitivity for insulin assay.

In this study, we have reported a novel fabrication technique for human serum albumin (HSA) imprinted composite bacterial cellulose nanofibers (MIP-cBCNFs) used for the depletion of HSA selectively from artificial blood plasma for proteomic applications. Molecular imprinting was achieved by using metal ion coordination interactions of N?methacryloyl?(L)?histidinemethylester (MAH) monomer and Cu(II) ions. MAH-Cu(II)-HSA complex was polymerized with bacterial cellulose nanofibers (BCNFs) under constant stirring at room temperature. The characterization of the MIP-cBCNFs was carried out by FTIR-ATR, SEM, contact angle measurements and surface area measurements. The adsorption experiments of HSA onto the MIP-BCNFs and NIP-BCNFs from aqueous HSA solutions were investigated in a batch system. The selectivity of the MIP-cBCNFs was investigated by using non-template human transferrin (HTR), and myoglobin (Myo). The relative selectivity coefficients of the MIP-cBCNFs were calculated as 4.73 and 3.02 for HSA/HTR and HSA/Myo molecules, respectively. In addition, the depletion of HSA from artificial human plasma was confirmed by SDS-PAGE and 2-D gel electrophoresis. As a result, it has been shown that metal ion coordination interactions contribute to specific binding of template when preparing MIP-cBCNFs for the depletion of HSA with a high adsorption capacity, significant selectivity and reusability. © 2018

The development of new biomaterials is needed to use in many areas such as protein purification, removal and drug release system. In this study, we fabricated hemoglobin (Hb) surface imprinting onto the bacterial cellulose nanofibers. The metal ions coordination was obtained with vinyl imidazole and Ni2+ ions. The selective purification of Hb was obtained using Hb-imprinted bacterial cellulose. The Scanning Electron Microscopy, Surface area, Transformed Infrared Spectroscopy, swelling tests and contact angle measurements were used for the characterization of Hb-imprinted and non-imprinted bacterial cellulose membranes. In addition, the adsorption studies were experimented with using the Hb aqueous solution in the batch systems at 2 h. In this study, the prepared bacterial cellulose was reported unique biomaterials for selective and sensitive purification of Hb with high adsorption capacity. The reusability of bacterial celluloses was demonstrated during the experiment.

The development of novel biocompatible and cost effective cryogel membrane which shows enhanced antimicrobial properties in order to use for several approaches such as wound dressing, scaffold or food packaging was aimed in this study. A super macro porous lysozyme imprinted cryogel membranes showing antibacterial effect against both Gram-positive and Gram-negative bacteria were prepared by using molecular imprinting technique. N-methacryloyl-(L)-histidine methyl ester (MAH) was used as the pseudo specific ligand and complexed with Cu++ in order to provide metal ion coordination between MAH and template molecule (lysozyme). Comparing the antibacterial activity of different lysozyme concentrations, cryogel membranes were prepared in three different concentrations. To synthesize Poly (hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methylester) P(HEMA-MAH) cryogel membrane, free radical polymerization initiated by N, N, N', N'-tetramethylene diamine (TEMED) and ammonium persulfate (APS) was carried out at -12 °C. The characterization of the lysozyme imprinted cryogel membrane was accomplished by using scanning electron microscopy (SEM), swelling degree measurements and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) spectroscopy. The cytotoxicity test of produced membrane was performed by using mouse fibroblast cell line L929. The antibacterial activity of P(HEMA-MAH) lysozyme molecular imprinted [P(HEMA-MAH) Lyz-MIP] cryogel membranes against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were determined by Kirby-Bauer membranes diffusion and viable cell counting methods. When the antibacterial effect of P(HEMA-MAH) Lyz-MIP cryogel membranes were evaluated, it was found that P(HEMA-MAH) Lyz-MIP cryogel membranes had stronger antibacterial effects against Gram-negative E. coli bacteria even in low lysozyme concentrations. In addition, 100% bacterial inhibition was detected for both of two bacteria at increasing lysozyme concentrations.

WOS:000612823000013 PubMed: 33383498 Boronic acids are important ligands used to selectively recognize and enrich compounds containing cis-diol groups such as nucleosides. In the present study, organic-inorganic hybrid [POSS-MAH-BPA] monolithic column was prepared for the first time in the literature as a new boronate affinity system for the recognition of nucleosides. The selectivity of the [POSS-MAH-PBA] boronate affinity monolithic column for the recognition of cis-diol containing adenosine nucleoside from its analogue molecule of deoxyadenosine triphosphate, dATP, noncis-diol containing compound was investigated both by UV and HPLC studies. When the relative selectivity coefficients are compared, the [POSS-MAH-PBA] boronate affinity monolithic column is 4.25 times more selective for adenosine than [POSS-MAH] monolithic column. Besides, to determine endogenous nucleosides in biological fluids, which may serve as non-invasive cancer biomarkers, nucleosides were spiked into the urine solutions and passed through the [POSS-MAH-PBA] boronate affinity monolithic column, and the nucleosides were confirmed by HPLC. The adenosine recognition capability of the [POSS-MAH-PBA] boronate affinity monolithic column with an average enrichment factor of 48.9-fold was apparently superior to that of the [POSSMAH] monolithic column. Methacryl Polyhedral Oligomeric Silsesquioxanes (POSS-MA) with nano-sized stable 3-dimensional architectures provided the advantage of being used as an adsorbent for the monolithic structure by providing high surface area, 507.60 m(2)/g, and enabling vinyl groups to function with amino acid-based MAH monomers capable of providing electrons to coordinate PBA. Recovery results of more than 90% for adenosine showed that the [POSS-MAH-PBA] boronate affinity monolithic column could be a promising adsorbent for selective adsorption of cis-diol containing compounds such as nucleosides.

In this study, we reported the design of a quartz crystal microbalance (QCM) sensors for selective insulin detection. In the first step, N-methacryloyl-(L) 3-histidine methyl ester (MAH) monomer was formed a complex with insulin. Then, 2-hydroxyethyl methacrylate and ethylene glycol dimethacrylate were mixed with MAH:insulin complex. Insulin-imprinted and non-imprinted QCM sensors were synthesized by ultraviolet polymerization for the insulin detection. Insulin-imprinted QCM sensors was characterized by the contact angle measurements, atomic force microscopy and ellipsometry. Limit of detection (LOD) was found as 0.00158 ng/mL for the insulin-imprinted QCM sensors. Selectivity of insulin-imprinted and non-imprinted QCM sensors was carried in the presence of glucagon and aprotinin. Insulin-imprinted QCM sensor for insulin detection was also examined in the artificial plasma.

Antibacterial micron-sized cryogels, so-called microcryogels, were prepared by cryogelation of gelatin and integration of lysozyme. Gelation yield, specific surface area, macro-porosity and swelling degree of the microcryogels were examined in order to characterize their physical properties. MTT method was utilized to measure cell viability of the gelatin microcryogels with a period of 24, 48, and 72 h and no significant decrease was observed at 72 h. Apoptotic staining assay also showed high viability at 24, 48, 72 h in parallel with the control group. The antibacterial performances of the gelatin microcryogels against

Immobilized metal ion affinity chromatography (IMAC) has become a widespread analytical and preparative separation method for therapeutic proteins, peptides nucleic acids, hormones, and enzymes. N-Methacryloyl-l-histidine Methyl Ester (MAH) monomer is recently used as a synthesized affinity ligand in IMAC. It is capable of chelating with many transition metal ions such as Zn2+ , Ni2+ , and Cu2+ ions through its histidine residue. In this way, proteins can bind selectively to these immobilized metal ions through MAH as a ligand in affinity chromatography. In this study, we applied the computational docking method on the interactions that occur between the MAH monomer and its complexes with Zn2+ ions as ligands and protein molecules as targets. MAH monomer was drawn and created using the Avogadro software as an optimization tool. Human insulin (Ins) molecule and horse heart cytochrome C (Cyt C) were selected as target proteins to interact with MAH monomer as affinity ligand. Automated docking software AutoDock v4.2 was used for docking of MAH monomer to Ins and Cyt C, respectively. The affinity ligand complexes with Zn2+ ions bound to one, two, and three moles of MAH were studied and compared separately. The lowest binding energies of Ins and Cyt C proteins in 1:1 mol ratio of MAH-Zn2+ were found as (-4.14) and (-4.92) kcal/mol, respectively.

Adenosine is an important molecule in the human body because it participates various biochemical processes, signalling in the physiological processes, and neurological disorders. In the current study, the surface imprinting method was used to prepare adenosine-imprinted magnetic core-shell polyvinylbutyral microbeads. These microbeads were utilized for quantification of adenosine in aqueous solution and control plasma in the range of 1–200 µM. The limit of detection was found to be 1.9 nM, which is quite sensitive compared with to some earlier studies. Fourier transform infrared spectroscopy, scanning electron microscopy, and a Zetasizer (particle size analyzer) were used for characterization of the prepared imprinted microbeads. To determine the efficiency of this method, selectivity experiments were conducted with adenosine-imprinted and non-imprinted magnetic core-shell polyvinylbutyral microbeads and with the competitive nucleosides cytidine, uridine, guanosine, and thymidine. Thermodynamic and kinetic studies were performed to assess adsorption of adenosine onto the adenosine-imprinted magnetic core-shell polyvinylbutyral microbeads from adenosine solution. The efficiency was linked to the specific surface reactivity, polarity and porosity of the imprinted microbeads.

*Topçu, Aykut Arif ( Aksaray, Yazar ), Human immunoglobulin M (hIgM) antibodies are considered as hopeful tools for diseases therapy. Therefore, chromatography approaches are used to purify hIgM with a single step. In this study, we prepared a poly(hydroxyethyl methacrylate) based immunoaffinity p(HEMA-I) cryogel column by using cyanamide to immobilize antihuman immunoglobulin on the p(HEMA) cryogel for purification of hIgM in aqueous solution and artificial human plasma. The characterization of the p(HEMA) cryogel column was performed by using a scanning electron microscope (SEM), micro-computerized tomography (µ-CT), Fourier transform infrared spectroscopy (FTIR), swelling degree and macro-porosity. Further, the optimizations of various parameters were performed such as, pH, ionic strength, temperature and concentration of hIgM in aqueous solutions. In addition, the Langmuir adsorption model was supported by experimental results. Maximum adsorbed amount of hIgM corresponded to 11.1 mg/g at pH 5.75 [morpholino ethanesulfonic acid (MES buffer)]. Our results indicated that the p(HEMA-I) cryogel column can be reused at least 10 times without significant loss in adsorption capacity. As a natural source, artificial human plasma was selected for hIgM adsorption and the purity of hIgM was evaluated using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). © 2020 by the authors. Licensee MDPI, Basel, Switzerland.

This study reports a sensitive sensor-based measurement technique for selective and sensitive detection of Cd(II) ions at low concentrations using ion-imprinted technology. Heavy metal pollution is an extremely hot topic on scientific research for several decades. Cd(II) is one of the most toxic and carcinogenic heavy metals. The limit of concentration of Cd(II) ions allowed to be found in the drinking water and industrial wastewater has been defined as 3 µg/L by the World Health Organization. Therefore, a simple, reliable and effective method is required for the determination of Cd(II) ions. Surface plasmon resonance sensor is the most commonly used optical sensors due to their unique ability for real-time monitoring the molecular binding events. We have proposed a sensitive experimental platform capable of achieving detection in 6–7 min. In this work, the benefits of three different approaches were compared according to their performance enhancement effects on sensors. Poly(hydroxyethyl methacrylate) thin-film, polymeric nanoparticles, and gold nanoparticles were separately used for designing sensors surface for the sensitive detection of Cd(II) ions. Combination of the signal enhancing properties of nanoparticles and ion-imprinting technique provided sensitive and selective detection with a comparatively low limit of detection value to the SPR sensor system. The limit of detection value has been defined as 0.01 µg/L for selective Cd(II) ions detection which is less than the value determined by the World Health Organization. The real time detection of Cd(II) ions from wastewater solutions (SPS Quality Control Material Waste Water Level 2) was also carried out by the SPR sensors.

Various changes in the environment can occur as drug delivery systems travel to the targeted area. Therefore, it is an important aspect to consider the effects of environmental changes such as pH and temperature on the release in the development of drug delivery systems. Microcryogels having predefined shape and size were fabricated as drug delivery systems and loaded with diclofenac sodium, a non-steroidal anti-inflammatory drug. Physicochemical, structural, and morphological properties of microcryogels were investigated by swelling, pore volume and porosity tests, infrared spectroscopy, and field emission scanning electron microscopy. Effects of medium pH on drug release were examined at release media with the pH 2.0 as simulated gastric juice, pH 7.4 as the simulated intestinal fluid/intravenous solution, pH 6.0 as a simulated medium during a normal wound healing, and pH 9.0 as a simulated medium for infected wounds. Effects of temperature on drug release were also analyzed at 37 °C as normal body temperature and 42 °C as inflammatory temperature. The obtained results showed that drug release was too low in acidic environment than those observed at higher pH values. Moreover, the release rates were higher at inflammatory temperature compared with the ones at normal body temperature.

Boronate affinity chromatography is a common purification method used for isolation and purification of cis-diol containing biomolecules. Poly (hydroxyethyl methacrylate-co-vinyl phenyl boronic acid) [P(HEMA-VPBA)] nanoparticles were prepared by miniemulsion polymerization to use in RNA purification methods. The P(HEMA-VPBA) nanoparticles were characterized by particle size distribution, surface area, Fourier transform infrared spectroscopy and atomic force microscopy. The effects of temperature, pH, RNA concentration and different salt types on RNA binding on the P(HEMA-VPBA) nanoparticles were examined. It was observed that RNA binding was increased with the increasing of pH and max RNA binding was obtained at pH 9.0. RNA binding capacity of the P(HEMA-VPBA) nanoparticles was increased from 167mg/g to 601mg/g with addition of BaCl2 to the binding medium. Maximum RNA binding capacity of the P(HEMA-VPBA) nanoparticles was 172mg/g at 1.0mg/mL initial RNA concentration. The P(HEMA-VPBA) nanoparticles were reusable for RNA binding. RNA was also extracted from Escherichia coli cells and purified successfully using the P(HEMA-VPBA) nanoparticles.

Cyanide is a hazardous substance and a toxic contaminant but it is found in the environment as a natural product of industrial activities. Biological methods are an alternative and promising potential approach to the conversion and destruction of other toxic byproducts that can be formed by both cyanide and chemical treatment. It is known that a lot of fungi, bacteria and some plants are used in biological treatment works. Trichoderma is a genus of fungi that has enzymes for cyanide destruction. It is known that microbial activity under aerobic conditions cyanide can be converted to ammonia and then nitrate by oxidation. Cryogels are gel matrices synthesized at temperatures below zero using monomeric or polymeric precursors. Polymeric network occurs while the solvent forms ice crystals. After the ice crystals melt, polymeric matrices with large pores are formed. Cryogels are used in a variety of areas of biotechnology, including chromatographic materials, carriers for immobilization of molecules and cells. In this study, poly(2-hydroxyethyl methacrylate) (PHEMA)-based Triccoderma spp. embedded supermacroporous cryogels were synthesized for cyanide destruction. The polymeric materials prepared were tested for cyanide degradation at different pH, temperature and initial concentrations to examine their suitability for this purpose.

Ermis, Nihal/0000-0002-0085-3076 WOS: 000419414800031 For selective and sensitive determination of L-phenylalanine (L-Phe) a novel and reliable electrochemical sensor has been developed based on molecular imprinting technique. Thiophen-3-carbonyl tryptophan (TP3C-Trp) has been synthesized and used as a novel monomer. L-Phe was used as template molecule and imprinted in presence of thiophen and thiophen-3-carbonyl tryptophan (TP3C-Trp), used as functional monomers. As a comparison a non-modified polymer surface was also prepared under same circumstances without template molecule, L-Phe. The characterization studies of both non-imprinted (NIP) and L-phenylalanine imprinted (MIP) electrochemical sensor surfaces were made by using atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), ellipsometry and contact angle measurements. The electrochemical characterization analysis were made via square wave and cyclic voltammetry. The linearity range and the detection limit of the developed sensor were obtained as 1.0 x 10(-8)-1.0 x 10(-7) M and 1.0 x 10(-9) M, respectively.

Creatinine imprinted cryogel (MIP) cartridge was prepared with functional monomer N-methacryloyl-(L)-histidinemethylester (MAH) under frozen conditions. Creatinine adsorption studies and selectivity of MIP cryogel were evaluated in aqueous solution and artificial urine sample. Maximum adsorbed amount of creatinine was calculated as 6.83 mg/g polymer for MIP cryogel. Langmuir and Freundlich adsorption isotherm models were used to investigate the adsorption behaviour of creatinine. In the artificial urine sample; recovery amounts of creatinine were found 34.7–46.2%. Creatinine imprinted cryogel (MIP) cartridge recognized creatinine, 4.58 and 4.37 times greater competitive molecules. MIP cryogel catridge was repeatedly used many times for adsorption desorption cycles. © 2017 Taylor & Francis Group, LLC.

The potential of the modified bacterial cellulose (BC) nanofibers was determined bearing metal ion coordination interactions to enhance the protein adsorption and binding capacity. Thus, a household synthesized metal chelating monomer, namely N-methacryloyl-L-histidine methylester (MAH), and a commercial metal chelating monomer, namely 4-vinylimidazole (VIm), were used to complex with metal ions Cu(II) and Ni(II) respectively for the synthesis of the modified BC nanofibers. The modified nanofibers were characterized by FT-IR, SEM and EDX measurements. The protein adsorption tests were carried out using hemoglobin as a model protein and it was determined that the maximum adsorption capacity of hemoglobin onto the modified BC nanofibers was found as 47.40 mg/g. The novel strategy for the preparation of metal chelated nanofibers was developed. © 2017 Elsevier B.V.

In this article, ion imprinted poly(hydroxyethyl methacrylate) (PHEMA) based supermacroporous cryogels were synthesized in the presence of a functional monomer, namely N-methacryloyl-histidine methyl ester (MAH), to be complexed with Ni(II) ions. Two types of cryogels (MIP1 and MIP2) were synthesized according to functional monomer/template [MAH/Ni(II)] complexing molar ratios. These cryogels were then characterized by swelling tests, FT-IR and SEM measurements and used for selective binding of Ni(II) ions from aqueous solutions and a certified material. The maximum adsorption capacities of MIP1 and MIP2 cryogels were found as 1.89 and 5.54 mg/g, respectively. Ni(II) imprinted cryogels exhibited excellent selectivity toward competitive metal ions [Fe(III), Cu(II) and Zn(II)] indicating important potential for selective removal of Ni(II) ions from aqueous solutions. In addition, Ni(II) imprinted cryogels were used repeatedly without a decrement in the binding capacity. © 2016 Elsevier B.V.

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 24.86 μg/L, 1.60%, and 349.6%, respectively.

In this study, a label-free, selective and sensitive microcontact imprinted capacitive biosensor was developed for the detection of Escherichia coli. The recognition of E. coli was successfully performed by this sensor prepared with the combination of microcontact imprinting method and capacitive biosensor technology. After preparation of bacterial stamps, microcontact-E. coli imprinted gold electrodes were generated using an amino acid based recognition element, N-methacryloyl-L-histidine methylester (MAH), 2-Hydroxyethyl methacrylate (HEMA) as monomers and ethyleneglycol dimethacrylate (EGDMA) as crosslinker under UV-polymerization. Real-time E. coli detection experiments were carried out within the range of 1.0×102–1.0×107 CFU/mL. The unique combination of these two techniques provides selective detection with a detection limit of 70 CFU/mL. The designed capacitive sensor has high selectivity and was able to distinguish E. coli when present together with competing bacterial strains which are known to have similar shape. In addition, the prepared sensor has the ability to detect E. coli with a recovery of 81–97% in e.g. river water.

Synthesis of melamine (ME) imprinted polymeric sorbent for use as solid phase extraction adsorbent was targeted and the benefits of the synthesis in the monolith format were combined with imprinting technology advantages. Melamine as template and 2-vinylimidazole-Cu 2 + as complexing agent were used as the first time for pre-complex formation, followed by the preparation of monolith by bulk polymerization method in the presence of ethyleneglycol dimethacrylate as crosslinker, azobisisobutyronitrile as initiator, and ethyl alcohol as solvent for a duration of 4 h at 80 °C. 1.0 M NaOH solution was used as a desorption agent to remove template. Non-imprinted monolith (NIP) were synthesized as a control without template in same receipt. The monolith samples were characterized by Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), elementary analysis, and Branauer- Emmett- Teller (BET) studies. Melamine adsorption from aqueous solution was studied in continuous mode, and some parameters such as pH, temperature, concentration and flow-rate were optimized for melamine adsorption. The maximum adsorption capacities were determined as 147.9 mg/g for imprinted polymer (MIP), 82.0 mg/g for non-imprinted polymer (NIP) and 4.0 mg/g for polymer without pre-complex (E) at 25 °C, and pH 5.0 with 500 ppm melamine initial concentration for 1.0 mL/min flow-rate. In addition to interaction characterized by metal coordination bond formation, non- covalent interactions were responsible for melamine adsorption. No significant change in adsorption performance was recorded after 10 consecutive adsorption-desorption cycles. Kinetic analysis indicated compliance with pseudo-second order kinetics. The Freundlich isotherm was found suitable for description of the process. Cyanuric acid (CY), aniline (AN), and phenol (PH) were used as competing agents in selectivity studies, and relative selectivity coefficients were calculated (k' CY = 4.45; k' AN = 7.08; k' PH = 3.98). The performance of melamine imprinted polymeric monolith (MIP) as solid-phase extraction adsorbent for extraction of melamine from milk samples was investigated and the recovery of melamine in spiked milk samples was 97.6% with the relative standard deviation (RSD) (8.1%).

Concanavalin A is a representative of the plant protein group known as lectins. Many lectin proteins have useful characteristics for studies on cell division and cell surfaces. In this study, a new adsorbent for the specific separation of Concanavalin A was prepared by applying a silica particle surface imprinting method. First, silica particles were activated via acidic treatment, and then, 3-methacryloyloxypropyl trimethoxysilane (MPTMS) was used for modification. For the preparation of Concanavalin A surface-imprinted silica particles (Con A-MISPs), N-methacryloyl- l -histidine methyl ester (MAH) was used as a functional monomer. The silica particles were characterized using a Zetasizer, scanning electron microscopy equipment (SEM), and Fourier transform infrared spectroscopy (FTIR). The effects of parameters such as the pH, initial concentration of Concanavalin A, and temperature on the adsorption of Concanavalin A were determined. The maximum Concanavalin A adsorption onto Con A-MISPs was observed to be 305.2 mg/g at a pH of 6. The reusability of the Con A-MISPs was approximately 93.5%. The non-imprinted silica particles (NISPs) were prepared in the same manner without Concanavalin A to compare the surface imprinting factor. Selective binding studies were carried out with lysozyme and hemoglobin molecules. The selectivity of the Con A-MISPs was also investigated by isolating Concanavalin A from Canavalia ensiformis. The purity of the Concanavalin A was shown by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE).

In this study, low molecular weight heparin immobilized P(HEMA) cryogels were fabricated for the removal of LDL-C in hypercholesterolemic human plasma. After characterization studies for P(HEMA) cryogels, effects of the parameters including medium pH, CNBr concentration, heparin concentration and contact time on heparin immobilization were investigated. Blood compatibility and cell adhesion tests were also performed, and platelet and leucocyte loss for P(HEMA)-Hp cryogels were found to be 2.95% and 4.91%, respectively. Maximum adsorption capacity for LDL-C from hypercholesterolemic human plasma was found to be 26.7 mg/g for P(HEMA)-Hp cryogel while it was only 1.67 mg/g for bare P(HEMA) cryogel. The P(HEMA)-Hp cryogels exhibit high desorption ratios up to 96% after 10 adsorption-desorption cycles with no significant decrease in the adsorption capacity. The findings indicated that these reusable P(HEMA)-based cryogels proposed good alternative adsorbents for removal of LDL-C.

Supermacroporous gels, called cryogels, are unique scaffolds that can be prepared by polymerization of monomer solution under sub-zero temperatures. They are widely used in many applications and have significant potential biomaterials, especially for biomedical applications due to their inherent interconnected supermacroporous structures and easy formation of composite polymers in comparison to other porous polymer synthesis techniques. This review highlights the fundamentals of supermacroporous cryogels and composite cryogels, and then comprehensively summarizes recent studies in preparation, functionalization, and utilization with mechanical, biological and physicochemical features, according to the biomedical applications. Furthermore, conclusions and outlooks are discussed for the use of these promising and durable supermacroporous composite cryogels.

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

The aim of this work is to develop drug carrier system with high loading capacity and controlled drug release profile for antibiotic release. For this purpose, composite molecularly imprinted nanofibers were prepared via in-situ graft polymerization of methacrylic acid as a monomer, N,N’-methylene bisacrylamide as a crosslinker and gentamicin sulfate as a template molecule onto surface-modified bacterial cellulose nanofibers. Gentamicin imprinted microparticles were fabricated onto bacterial cellulose nanofibers resulting in the formation of composite BC nanofibers. Thus, the composite nanofibers incorporated with gentamicin imprinted microparticles were achieved to fabricated. The in-vitro drug release tests were performed to evaluate the release performance of the resultant composite nanofibers at 37 °C. Also, kinetic models were applied to the drug release data. It was determined that the drug release from the composite molecularly imprinted nanofibers fit well in the Korsmeyer-Peppas model. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group. 2-s2.0-85062989858 PubMed: 30773098

WOS: 000471359400002, Molecular imprinting technique is used to design artificial creatinine receptor on the gold surface of surface plasmon resonance (SPR) chip using N-methacryloyl-(L)-histidine methyl ester (MAH), as a functional monomer. Surface characterization of SPR sensor chip is performed with atomic force microscope (AFM), ellipsometry and contact angle measurements. Creatinine imprinted SPR sensor is characterized with a linear range between 1 and 100 mM and limit of detection (LOD) and limit of quantification (LOQ) of creatinine are found 57 mu M and 190 mu M, respectively. N-hydroxysuccinimide (NHS) and creatine molecules are selected to examine the selectivity of creatinine imprinted SPR sensor. Reusability studies of SPR sensor is determined in urine mimic samples., Republic of Turkey, Ministry of Science, Industry and Technology [0505_TGSD.2015_2], This study was funded and supported by Republic of Turkey, Ministry of Science, Industry and Technology (Grand No. 0505_TGSD.2015_2).

The application of interconnected supermacroporous cryogels as support matrices for the purification, separation and immobilization of whole cells and different biological macromolecules has been well reported in literature. Cryogels have advantages over traditional gel carriers in the field of biochromatography and related biomedical applications. These matrices nearly mimic the three-dimensional structure of native tissue extracellular matrix. In addition, mechanical, osmotic and chemical stability of cryogels make them attractive polymeric materials for the construction of scaffolds in tissue engineering applications and in vitro cell culture, separation materials for many different processes such as immobilization of biomolecules, capturing of target molecules, and controlled drug delivery. The low mass transfer resistance of cryogel matrices makes them useful in chromatographic applications with the immobilization of different affinity ligands to these materials. Cryogels have been introduced as gel matrices prepared using partially frozen monomer or polymer solutions at temperature below zero. These materials can be produced with different shapes and are of interest in the therapeutic area. This review highlights the recent advances in cryogelation technologies by emphasizing their biomedical applications to supply an overview of their rising stars day to day.

The authors describe a test stripe for fluorometric determination of the endocrine disruptor bisphenol A (BPA). Graphene quantum dots (GQDs) were immobilized on molecularly imprinted nanoparticles which then were placed on nitrocellulose paper. The GQDs display blue fluorescence (with excitation/emission peaks at 350/440 nm) which is reduced in the presence of BPA. The test stripe has a 43.9 ± 0.8 μg·L−1 limit of detection in case of water samples. The stripe was applied to the determination of BPA in (spiked) tap water and sea water, and the LODs were found to be 1.8 ± 0.2 μg·L−1 and 4.2 ± 0.5 μg·L−1, respectively. Structural analogs of BPA, such as aminophenol, phenol, hydroquinone and naphthol were found not to interfere., Recep Üzek thanks to TUBITAK for the given scholarship. We acknowledge support from MINECO, Spain for MAT2017-87202-P and Graphene Flagship Core Project 2 (Ref: 785219). ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706). This work is also funded by the CERCA Programme / Generalitat de Catalunya.

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. © 2016 Elsevier B.V.

Immobilized metal ion affinity chromatography is one of the methods used for the adsorption of proteins. In this study, poly(glycidyl methacrylate) cryogel discs were prepared by free radical polymerization. The metal chelating groups were polymeric chain of poly-( l )-histidine (mol wt ≥ 5000) having poly-imidazole ring sequence. Then, Cu(II), Zn(II), and Ni(II) ions were separately chelated on the poly-( l )-histidine immobilized poly(glycidyl methacrylate) cryogel discs to be used in immobilized metal ion affinity chromatography separation of lysozyme. The swelling test, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller, and scanning electron microscopy were performed to characterize both poly(glycidyl methacrylate) and poly-( l )-histidine immobilized poly(glycidyl methacrylate) cryogel discs. The effects of the pH, lysozyme concentration, adsorption time, and ionic strength on the adsorption capacity were studied. These parameters were varied between 4.0 and 8.0 for pH, 0.0 and 2.0 mg/ml for initial lysozyme concentration, 0 and 120 min for adsorption time, and 0.0 and 1.0 µM for ionic strength. The maximum lysozyme adsorption capacity of the Cu(II), Zn(II), and Ni(II) ions chelated poly-( l )-histidine immobilized poly(glycidyl methacrylate) cryogel discs was 36.4, 26.8, and 17.3 mg/g cryogel, respectively. Desorption of lysozyme from cryogel discs was easily achieved by 1.0 M NaCI solution. Repeated adsorption-elution processes showed that these cryogel discs were suitable for repeatable lysozyme adsorption. Adsorption isotherms fitted to Langmuir model and adsorption kinetics suited to pseudo-second order model. Thermodynamic parameters (i.e. ΔH°, ΔS°, ΔG°) were also calculated from Langmuir isotherms at different temperatures.