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In this work, microscale poly-2-hydroxyethyl methacrylate [p(HEMA)]-based cryogels were fabricated as a drug delivery material using molecular imprinting technology for controlled release of mitomycin C (MMC) as an anti-cancer drug. MMC imprinted pHEMA-based micro cryogels (pMIPs) were prepared according to free-radical polymerization by using N-methacryloyl-(l)-histidine methyl ester (MAH) as an amino-acid-based polymerizable functional monomer using a micro stencil array chip with microwells of 200 μm diameter and 500 μm thickness. Following that, scanning electron microscope, swelling test, and Fourier Transform Infrared Spectroscopy were used for the characterization studies of pMIPs. After the characterization studies, MMC release performance of pMIPs was investigated towards the different pH values and various MMC concentrations in the aqueous solutions. The in vitro cytotoxicity studies of the pMIPs and the non-imprinted pHEMA based micro cryogels (pNIPs) were examined using L929 cell line. According to the experimental findings, the incorporation of MAH monomer could increase the release performance of pMIPs and the release of MMC from the pMIPs was non-Fickian in the aqueous solution. pMIPs did not show any noticeable cytotoxicity and could be potentially used as a new drug carrier for MMC release.

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

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.

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.

Myoglobin is a primary iron, and oxygen-binding protein of muscle tissues and levels can be an important diagnostic biomarker for acute myocardial infarction, myocardial necrosis, or other cardiac diseases. The establishment of myoglobin recognition systems is important because of its protein's structural and functional values in physiology, biochemistry, and diagnostic value in some damaged muscle tissue and cardiac diseases. For this purpose, we used molecular imprinting technique for myoglobin recognition from aqueous solutions and human plasma. In the first step, myoglobin-imprinted poly(hydroxyethyl methacrylate) (PHEMA) cryogels (MGb-MIP) were prepared, and optimum myoglobin adsorption conditions were determined. Selectivity experiments have been done with the competitive proteins, and myoglobin adsorption from IgG and albumin-free human plasma was studied. The purity of the desorbed samples was determined with SDS-PAGE. The desorption efficiency and reusability of the MGb-MIP cryogels were tested, and it was shown that without any significant loss in the adsorption capacity, MGb-MIP cryogels can be used a number of times for myoglobin recognition and separation.

A new reactive capillary monolith as an alternative to the commonly employed glycidyl methacrylate-based stationary phases in capillary electrochromatography (CEC) applications was synthesized and post-functionalized with charge-bearing groups. For this purpose, a hydrophilic capillary monolith with reactive 3-chloro-2-hydroxypropyl moiety was first obtained by the copolymerization of a new methacrylate-based monomer, 3-chloro-2-hydroxypropyl methacrylate (HPMA-Cl), with a methacrylic crosslinking agent, ethylene glycol dimethacrylate (EDMA). The presence of 3-chloro-2-hydroxypropyl functionality in poly(HPMA-Cl-co-EDMA) monolith allowed the synthesis of monoliths carrying strongly ionizable anionic, cationic or neutral groups such as sulfonic acid, quaternary ammonium or octadecyl, respectively, via simple and single-stage reactions. In the present study, a reactive poly(HPMA-Cl-co-EDMA) capillary monolith was functionalized with sodium bisulfite (NaHSO3) to have a strongly ionizable sulfonic acid group on the monolith. The resulting monolith providing cathodic electroosmotic flow in CEC was successfully used for the separation of phenol derivatives. The theoretical plate numbers up to 63,000 plates/column were achieved. The results showed that a new promising, reactive support that could be functionalized with different chromatographic ligands for different chromatographic applications was obtained in the study.

Poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) [poly(HEMA-GMA)] cryogel was synthesized by cryopolymerization technique at frozen temperature. Iminodiacetic acid (IDA) was then attached covalently to the cryogel as a chelating agent. Then, poly(HEMA-GMA)-IDA cryogel was chelated with Ni(II) ions and this novel metal affinity support was used for adsorption of urease from its aqueous solution. Urease adsorption experiments were carried out in a continuous system by using a peristaltic pump. Maximum urease adsorption onto poly(HEMA-GMA)-IDA-Ni(II) cryogel was found to be 11.30 mg/g cryogel at pH 5.0 acetate buffer and in 25 °C medium temperature. Urease adsorption capacity decreased with increasing ionic strength and increasing chromatographic flow rate. Adsorption kinetics of urease onto poly(HEMA-GMA)-IDA-Ni(II) cryogel was also investigated and it was found that Langmuir adsorption model is applicable for this adsorption study. This novel immobilized metal affinity chromatography support was used 10 times without any decrease at their adsorption capacity. It was also observed that urease enzyme was repeatedly adsorbed and desorbed without significant lost in enzymatic activity.

Supermacroporous poly(2-hydroxyethyl methacrylate) [poly(HEMA)] monolithic cryogel was prepared by radical cryocopolymerization of HEMA with N,N'-methylene bisacrylamide as crosslinker. Reactive Green 5 dye was immobilized to the cryogel with nucleophilic substitution reaction, and this dye attached cryogel column was used for affinity purification of papain from Carica papaya latex. Reactive Green 5-immobilized poly(HEMA) cryogel was characterized by swelling studies, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy dispersive X-ray analysis. Maximum papain adsorption capacity was found to be 68.5 mg/g polymer while nonspecific papain adsorption onto plain cryogel was negligible (3.07 mg/g polymer). Papain from C. papaya was purified 42-fold in single step with dye attached cryogel, and purity of papain was shown by silver-stained sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

WOS: 000290279000009, PubMed ID: 21437619, This study presents the development of targeted and antibody cross-linked QDs and explores whether these bioconjugates could specifically and effectively label Cu/Zn superoxide dismutase (SOD1) on fixed cells and tissues. QD-antibody conjugation was achieved by using our previously invented AmiNoacid (monomer) Decorated and Light Underpining Conjugation Approach (ANADOLUCA) method. In this method, we have used a photosensitive aminoacid monomer having ruthenium complex which is a synthetic and inexpensive material for the preparation of bioconjugates. Its specificity was demonstrated by extracting the active enzyme from rat liver lysate by using the bioconjugate. It provided accurate antibody orientation, high specificity and mechanic stability. The protocol steps for QD-antibody conjugation and specimen preparation were described in detail. The nanobioconjugates were prepared under mild conditions (for example in day light), independent of pH and temperature, without affecting conformation and function of protein. This protocol is simple, inexpensive and can be successfully adapted to detect other targets on different cell types and tissues.

A new metal-chelate adsorbent utilizing 2-methacryloylamidohistidine (MAH) was prepared as a metalchelating ligand. MAH was synthesized using methacryloly chloride and histidine. Monosize nanospheres with an average diameter of 450 nm were produced by emulsion polymerization of 2-hydroxyetylmethacrylate (HEMA) and MAH. Then, Fe3+ ions were chelated directly onto the monosize nanospheres. Mon-poly(HEMA-MAH) nanospheres were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and elemental analysis. Fe3+ chelated monosize nanospheres were used in ferritin adsorption from an aqueous solution. The maximum ferritin adsorption capacity of Fe3+-chelated mon-poly(HEMAMAH) nanospheres was 202 mg/g at pH 4.0 in acetate buffer. The non-specific ferritin adsorption on the monpoly( HEMA-MAH) nanospheres was 20 mg/g. The adsorption behavior of ferritin could be modeled using both Langmuir and Freundlich isotherms. The adsorption capacity decreased with increasing ionic strength of the binding buffer. High desorption ratios (> 95% of the adsorbed ferritin) were achieved with 1.0 M NaCl at pH 7.0. Ferritin could be repeatedly adsorbed and desorbed with the Fe3+-chelated mon-poly(HEMA-MAH) nanospheres without significant loss of adsorption capacity.

WOS: 000290577600025, The nanoparticle comprises a superparamagnetic iron oxide nanoparticle core conjugated with trimethoxylsilyl propylmethacrylate (TMSPM) and methacryloylamido serine (MASE), methacryloylamido histidine (MAH), methacryloylamido glutamic acid (MAGA) monomers, and p-nitrophenyl palmitate (p-NPP) which is a substrate of lipase as a template molecule, which enables the creation of lipase active region. The resulting hybrid superparamagnetic nanotraps are magnetically separable, highly active, and stable under harsh conditions. In this study, the advantages of high selectivity of molecular imprinting technique have used to get mimic lipase for the synthesis of methyl jasmonate and methyl oleate.

WOS: 000280240600013, Molecular imprinted polymers (MIPs) as a recognition element for sensors are increasingly of interest and MIP nanoclusters have started to appear in the literature. In this study, we have proposed a novel thiol ligand-capping method with polymerizable methacryloylamido-cysteine (MAC) attached to gold-silver nanoclusters, reminiscent of a self-assembled monolayer and have reconstructed surface shell by synthetic host polymers based on molecular imprinting method for recognition. In this method, methacryloylamidoantipyrine-terbium ((MAAP)(2)-Tb(III)) has been used as a new metal-chelating monomer via metal coordination-chelation interactions and dipicolinic acid (DPA) which is main participant of Bacillus cereus spores used as a model. Nanoshell sensors with templates give a cavity that is selective for DPA. The DPA can simultaneously chelate to Tb(III) metal ion and fit into the shape-selective cavity. Thus, the interaction between Tb(III) ion and free coordination spheres has an effect on the binding ability of the gold-silver nanoclusters nanosensor. The binding affinity of the DPA imprinted nanoclusters has been investigated by using the Langmuir and Scatchard methods, and the respective affinity constants (K (affinity)) determined were found to be 1.43 x 10(4) and 9.1 x 10(6) mol L(-1).

Adsorption chromatography is increasingly used for protein separations and biomedical applications. Therapeutic molecules such as antibodies, cytokines, therapeutic DNA, and plasma proteins must be purified before characterization and utilization. Use of immunoglobulins as immunodiagnostic and therapeutic tools has initiated many attempts to develop new adsorbents for their separation. Protein A and protein G are the affinity ligands most widely used for separation of immunoglobulins. These proteins are reliable, and have good selectivity and specificity, but are very expensive. Much attention has therefore been devoted to developing alternative methods for separation of immunoglobulins. Pseudobiospecific ligands, for example metal ions and amino acids, can be used for separation of a wide range of biological molecules. In this study, IgG1, IgG2, and IgG3, three subclasses of human IgG, were separated from human serum using the amino acid histidine grafted on to bisoxirane-activated Sepharose, as pseudobiospecific adsorbent. Adsorption of IgG from different animal species on the same chromatographic adsorbent was also tested. The high recovery and purification on histidyl–bisoxirane–Sepharose gel of IgG from all the sources tested compared well with results obtained by use of protein A–Sepharose gel.

The purpose of this study was to prepare a novel ion-imprinted nanoparticle to remove Cr(VI) ions from waste water. For this, Cr(VI) ions were complexed with 2-methacryloylamido histidine (MAH) and then Cr(VI)-imprinted poly(HEMAH) nanoparticles were synthesized by surfactant-free emulsion polymerization technique. The templates, Cr(VI) ions, were removed from the nanoparticles using 0.1 M of HNO3 solution. The specific surface area of the Cr(VI)-imprinted poly(HEMAH) nanoparticles was found to be 1,397.85 m2/g, and the particle size was calculated as 155.3 nm. These Cr(VI)-imprinted nanoparticles were used for the adsorption/desorption of Cr(VI) ions from its aqueous solutions. The effects of initial Cr(VI) concentration and medium pH on the Cr(VI) adsorption capacity were also studied. The maximum adsorbed amount of Cr(VI) on the imprinted nanoparticles was found to be 3,830.58 mg/g nanoparticle in pH 4.0. In order to investigate the selectivity of the imprinted nanoparticle, adsorption studies were repeated using Cr(III) ions. The selectivity results demonstrated that Cr(VI)-imprinted poly(HEMAH) nanoparticles showed high affinity for the Cr(VI) ions than Cr(III). The Cr(VI)-imprinted nanoparticles were used several times without decreasing their Cr(VI) adsorption capacities.

WOS: 000318550000036, Integrin family members are the main mediators of cell adhesion to the extracellular matrix and active as intra- and extracellular signaling molecules in a variety of processes. They bind to their ligands by interacting with short amino acid sequences, that is, RGD (arginine-glycine-aspartic acid) sequence. RGD sequences have been used to enhance cell binding to artificial surfaces, so RGD mimics have been used to block integrin binding to its ligand. Integrin-ligand interactions are dependent on divalent cations, and Mg2+ provide higher-affinity binding to ligand for many integrins. In this study, we have designed new integrin antagonists using methacryloyl amidoaspartic acid (MAASP) monomer-conjugated silanized super paramagnetic iron oxide nanoparticles (SPIONs, the size of the nanoparticles was verified with an average size of 32.6 nm) and poly(MAASP-co-EDMA) shell-decorated silanized SPIONs. Several mechanisms have been proposed to describe uptake of modified SPIONs into the cells, including receptor-mediated endocytosis. Our aim is to bind these modified SPIONs to the integrin-mediated aspartic acid ends of MAASP monomers and block integrin binding to their ligand.

Aluminum has recently been recognized as a causative agent in dialysis encephalopathy, osteodystrophy, and microcytic anemia occurring in patients with chronic renal failure who undergo long-term hemodialysis. Only a small amount of Al(III) in dialysis solutions may give rise to these disorders. Magnetic poly(2-hydroxyethyl methacrylate) (mPHEMA) beads in the size range of 80–120 μm were produced by free radical co-polymerization of HEMA and ethylene dimethacrylate (EDMA) in the presence of magnetite particles (Fe3O4). Then, metal complexing ligand alizarin yellow was covalently attached onto mPHEMA beads. Alizarin yellow loading was 208 μmol/g. These beads were used for the removal of Al(III) ions from tap and dialysis water in a magnetically stabilized fluidized bed. Al(III) adsorption capacity of the beads decreased with an increase in the flow-rate. The maximum Al(III) adsorption was observed at pH 5.0. Comparison of batch and magnetically stabilized fluidized bed (MSFB) maximum capacities determined using Langmuir isotherms showed that dynamic capacity (17.5 mg/g) was somewhat higher than the batch capacity (11.8 mg/g). The dissociation constants for Al(III) were determined using the Langmuir isotherm equation to be 27.3 mM (MSFB) and 6.7 mM (batch system), indicating medium affinity, which was typical for pseudospecific affinity ligands. Al(III) ions could be repeatedly adsorbed and desorbed with these beads without noticeable loss in their Al(III) adsorption capacity. Adsorption of Al(III) demonstrate the affinity of magnetic dye-affinity beads. The MSFB experiments allowed us to conclude that this inexpensive sorbent system may be an important alternative to the existing adsorbents in the removal of aluminium.