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In addition to understanding and explaining the functions of proteins, the need for low-cost, easy and efficient purification methods has been increasing in the field of protein purification, which is also important for enzyme production. In this context, an alternative approach has been developed for the purification of thrombin, which has a crucial role in the hemostatic process, via thrombin imprinted microcryogels that allow reuse and have high selectivity. The characterization studies of the microcryogels were accomplished with micro-computed tomography (µCT), scanning electron microscopy (SEM), optical microscope, surface area measurements (BET analyses) and swelling test measurements. By scanning various parameters affecting thrombin adsorption, the maximum thrombin adsorption capacity (Qmax) was found to be 55.86 mg/g. Also, the selectivity of microcryogels was investigated with the competitive agents and reusability studies were performed. The purity of thrombin was evaluated by Fast Performance Liquid Chromatography (FPLC) method. Experimental results indicated that adsorption of thrombin by the developed microcryogels fit the Langmuir isotherm model (Qmax: 55.86 mg/g, R2: 0.9505) and pseudo-second order for three different thrombin concentrations (R2: 0.9978, R2: 0.9998, R2: 0.9999).
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Impressão Molecular , Trombina , Microtomografia por Raio-X , Cromatografia de Afinidade/métodos , Cromatografia Líquida , Microscopia Eletrônica de Varredura , Adsorção , Impressão Molecular/métodos , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Adenosine nucleoside is an important molecule in human physiology. The levels of adenosine nucleoside in urine and plasma are directly or indirectly related to diseases such as neurodegenerative diseases and cancer. In the present study, adenosine-imprinted and non-imprinted poly(2-hydroxyethyl methacrylate-methacrylic acid) (poly(HEMA-MAA)) surface plasmon resonance (SPR) nanosensors were prepared for the determination of adenosine nucleoside. First, MAA/adenosine pre-polymerization complexes were prepared at different molar ratios using adenosine as a template molecule and methacrylic acid (MAA) as a monomer, and SPR nanosensor surfaces were optimized by determining the highest imprinting factor of the chip surfaces. The surfaces of adenosine-imprinted and non-imprinted SPR nanosensors were characterized by using atomic force microscopy, ellipsometry, and contact angle measurements. Kinetic analyses were made with different concentrations in the range of 0.5-400.0 nM for the detection range with a pH 7.4 phosphate buffer solution. The limit of detection in adenosine aqueous solutions, artificial plasma, and artificial urine was determined to be 0.018, 0.015, and 0.013 nM, respectively. In the selectivity analysis of the developed nanosensors, the selectivity of adenosine SPR nanosensors in solutions at different concentrations was determined by using guanosine and cytidine nucleosides. The relative selectivity coefficients of adenosine-imprinted SPR nanosensors for adenosine/cytidine and adenosine/guanosine are 3.836 and 3.427, respectively. Since adenosine-imprinted SPR nanosensors are intended to be used in medical analysis and research, adenosine analysis has also been studied in artificial urine and artificial plasma samples.
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In this study, magnetic poly(ethylene glycol dimethacrylate-N-methacryloyl-(L)-glutamic acid) (mPEGDMA-MAGA) particles were prepared by the dispersion polymerization in order to purify thrombin effectively. mPEGDMA-MAGA particles were synthesized by adding different ratios of magnetite (Fe3O4) to the medium in addition to the monomer phases EGDMA and MAGA. The characterization studies of mPEGDMA-MAGA particles were used by fourier transform infrared spectroscopy, zeta size measurement, scanning electron microscopy and electron spin resonance. mPEGDMA-MAGA particles were used in thrombin adsorption studies from aqueous thrombin solutions in both batch and magnetically stabilized fluidized bed (MSFB) system. Maximum adsorption capacity in pH 7.4 phosphate buffer solution is 964 IU/g polymer and 134 IU/g polymer in MSFB system and batch system, respectively. The developed magnetic affinity particles enabled the separation of thrombin from different patient serum samples in one step. It has also been observed that magnetic particles can be used repeatedly without significant reduction in adsorption capacity.
Assuntos
Ácido Glutâmico , Trombina , Humanos , Concentração de Íons de Hidrogênio , Metacrilatos/química , Polietilenoglicóis , Adsorção , Fenômenos MagnéticosRESUMO
One of the primary purposes of proteomic studies is to analyze the proteins in the blood to be considered as biomarkers. Albumin, which constitutes the majority of total serum proteins, complicates the discovery of low-density proteins that are important for the diagnosis of diseases. Based on this, an alternative approach for albumin depletion was developed in this study by covalently attached Cibacron Blue 3GA (CB) to magnetic microcryogels. After detailed characterization of CB attached magnetic microcryogels synthesized via a microstencil array chip, albumin adsorption studies were performed to examine the optimum depletion conditions. In the presented study, the maximum albumin adsorption capacity (Qmax) was calculated as 149.25 mg/mL in pH 5.0 acetate buffer solution, which is the optimum pH value for albumin. Experimental studies have demonstrated that CB-attached magnetic microcryogels can be reused without loss of performance for albumin depletion after 10 adsorption-desorption cycles.
Assuntos
Albumina Sérica Humana , Albumina Sérica , Humanos , Albumina Sérica/química , Ligantes , Proteômica , Cromatografia de Afinidade/métodos , Adsorção , Fenômenos Magnéticos , Triazinas/químicaRESUMO
As a general approach Fab immobilized immunoaffinity cryogels for human serum albumin purification is presented in this article. The directed immobilization of antibodies, which have been used as diagnostic and therapeutic agents in applications recently, has brought a different perspective to the purification method. In our study to shed light on this method, anti-HSA Fab fragment immobilized poly(hydroxylethyl methacrylate-N-methacryloyl-(l)-cysteine) (PHEMAC-Fab) and PHEMAC cryogels were prepared for the purification of human serum albumin (HSA). The specific surface areas of the PHEMAC-Fab and PHEMAC cryogels were calculated as 38.6 m2/g, and 20.0 m2/g, respectively. In comparison, the maximum swelling ratio was observed in the PHEMAC-Fab cryogel and more water was absorbed than the PHEMAC cryogel. While the macropore ratio in the PHEMAC-Fab cryogel is 54.3%, the macropore ratio of the PHEMAC cryogels is 41.6%. The results obtained here showed that anti-HSA cryogel prepared by immobilization of Fab fragments can be an alternative to traditional immunoaffinity techniques for HSA purification.
Assuntos
Criogéis , Albumina Sérica Humana , Adsorção , Humanos , Fragmentos Fab das Imunoglobulinas , MetacrilatosRESUMO
In the study, purification of ovalbumin was performed by modifying polyamide hollow fiber membranes using immobilized metal affinity chromatography technique. For this purpose, firstly polyethyleneimine (PEI) solutions of different concentrations were attached to hollow fiber membranes. Then, Cu(II), Ni(II) and Zn(II) metal ions were chelated separately to polyethyleneimine attached hollow fiber membranes. Characterization studies of modified hollow fiber membranes were performed with scanning electron microscopy (SEM). Also, the surface area was measured with the Brunner Emmet Teller (BET) method and the porosity was measured with mercury porosimeter. pH, ionic strength, initial ovalbumin concentration, temperature and reusability parameters affecting adsorption capacity were investigated. The maximum ovalbumin adsorption capacities of hollow fiber membranes were found to be 317 mg/g for Cu(II), 169 mg/g for Ni(II) and 101 mg/g for Zn(II), respectively. Desorption ratio of metal ions were calculated as 91.6% for Cu(II), 92.9% for Ni(II) and 91.8% for Zn(II), which are quite high and suitable. When examined in terms of adsorption isotherm models, it was concluded that the Langmuir model is suitable. Purification of ovalbumin from egg white was carried out by fast performance liquid chromatography (FPLC), and the purity of ovalbumin was evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) method.
Assuntos
Clara de Ovo , Nylons , Adsorção , Concentração de Íons de Hidrogênio , Íons , Membranas Artificiais , Metais/química , Nylons/química , Ovalbumina , PolietilenoiminaRESUMO
In this study, we designed a surface plasmon resonance (SPR) biosensors based on molecular imprinting to detect low amounts of thrombin directly in a short time, both in thrombin aqueous solutions and in patient serum samples. For this purpose, the thrombin imprinted and non-imprinted SPR biosensors were prepared by integrating the synthesized thrombin imprinted and non-imprinted nanoparticles on the allyl mercaptan modified gold SPR chip surface. The kinetic studies were performed with a thrombin concentration range from 0.1 to 400 pM with a detection limit of approximately 0.017 pM in thrombin aqueous solution. Morever, the limit of detection was found to be 0.033 pM in patient serum samples. When the selectivity of the thrombin imprinted SPR biosensors was compared with the competing molecules as bovine serum albumin and lysozyme, it was showed that the thrombin was 4.58 times and 3.99 times more selective than the bovine serum albumin and lysozyme molecules, respectively. The shelf life and reusability of the designed SPR biosensor showed that there was a 12.93% decrease in the performance according to the kinetic analyzes that performed after 8 months. In addition, thrombin detection from the patient serum samples was performed using both SPR biosensor and the enzyme-linked immunosorbent assay methods, and were calculated recoveries.
Assuntos
Técnicas Biossensoriais , Nanopartículas , Técnicas Biossensoriais/métodos , Humanos , Cinética , Muramidase , Soroalbumina Bovina , Ressonância de Plasmônio de Superfície/métodos , TrombinaRESUMO
In this study, the curcumin imprinted and the non-imprinted poly(2-hydroxyethyl methacrylate-N-methacryloyl-L-tryptophan) (poly(HEMA-MATrp)) nanoparticle based surface plasmon resonance (SPR) nanosensors were prepared for the detection of curcumin and characterized by zeta-size analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. After, the curcumin imprinted and the non-imprinted nanoparticles are attached on the surface of SPR chips. The curcumin imprinted and the non-imprinted SPR nanosensors are characterized by using atomic force microscope, ellipsometer, and contact angle measurements. Kinetic studies were carried out with curcumin aqueous solution at a concentration range of 0.01-150 mg/L using the curcumin imprinted and the non-imprinted SPR nanosensors. In all kinetic analysis, the response time is 14 min for equilibration, adsorption, and desorption cycles. The limit of detection and limit of quantification for the curcumin imprinted SPR nanosensors was 0.0012 mg/L and 0.0040 mg/L, respectively. The validity of the curcumin imprinted SPR nanosensors in real samples was carried out using liquid chromatography-tandem mass spectrometry (LC-MS).
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Molecularly imprinted polymer-based surface plasmon resonance sensor prepared using silver nanoparticles was designed for the selective recognition of Penicillin G (PEN-G) antibiotic from both aqueous solution and milk sample. PEN-G imprinted sensors (NpMIPs) SPR sensor was fabricated using poly (2-hydroxyethyl methacrylate-N-methacroyl-(L)-cysteine methyl ester)-silver nanoparticles-N-methacryloyl-L-phenylalanine methyl ester polymer by embedding silver nanoparticles (AgNPs) into the polymeric film structure. In addition, a non-imprinted (NpNIPs) SPR sensor was prepared by utilizing the same polymerization recipe without addition of the PEN-G template molecule to evaluate the imprinting effect. FTIR-ATR spectrophotometer, ellipsometer, contact angle measurements were used for the characterization of NpMIPs SPR sensors. The linear concentration range of 0.01-10 ng/mL PEN-G was studied for kinetic analyses. The augmenting effect of AgNPs used to increase the surface plasmon resonance signal response was examined using polymer-based PEN-G imprinted (MIPs) sensor without the addition of AgNPs. The antibiotic amount present in milk chosen as a real sample was measured by spiking PEN-G into the milk. According to the Scatchard, Langmuir, Freundlich and Langmuir-Freundlich adsorption models, the interaction mechanism was estimated to be compatible with the Langmuir model.
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In this work, a surface plasmon resonance (SPR) based immunosensor was prepared by the immobilization of the amine-functionalized gold nanoparticles (N-AuNPs) on the sensing surface to sense immunoglobulin M (IgM) antibodies in the aqueous solution and artificial plasma. The characterization studies of SPR based immunosensor for IgM detection were performed with scanning electron microscope (SEM), contact angle measurements, and ellipsometry. Kinetic studies for the IgM immunosensor were carried out in the range of 1.0 to 200 ng/mL IgM concentrations in an aqueous solution. The total IgM analysis time including adsorption, desorption, and regeneration cycles was nearly 10 min for the prepared immunosensor. The limit of detection (LOD) and limit of quantification (LOQ) were found as 0.08 and 0.26 ng/mL, respectively. The reusability of the proposed immunosensor was tested with 6 consecutive adsorption-desorption, and regeneration cycles. Also, enzyme-linked immunosorbent assay (ELISA) method was utilized in the validation of the immunosensor.
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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.
Assuntos
Impressão Molecular , Técnicas Biossensoriais , Insulina , Polímeros Molecularmente Impressos , Polímeros , Quartzo , Técnicas de Microbalança de Cristal de QuartzoRESUMO
Cryogels are interconnected macroporous materials that are synthesized from a monomer solution at sub-zero temperatures. Cryogels, which are used in various applications in many research areas, are frequently used in biomedicine applications due to their excellent properties, such as biocompatibility, physical resistance and sensitivity. Cryogels can also be prepared in powder, column, bead, sphere, membrane, monolithic, and injectable forms. In this review, various examples of recent developments in biomedical applications of injectable cryogels, which are currently scarce in the literature, made from synthetic and natural polymers are discussed. In the present review, several biomedical applications of injectable cryogels, such as tissue engineering, drug delivery, therapeutic, therapy, cell transplantation, and immunotherapy, are emphasized. Moreover, it aims to provide a different perspective on the studies to be conducted on injectable cryogels, which are newly emerging trend.
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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.
Assuntos
Criogéis , Muramidase , Adsorção , Animais , Antibacterianos/farmacologia , Escherichia coli , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Camundongos , Staphylococcus aureusRESUMO
In this study, we designed a simple, rapid, sensitive and selective surface plasmon resonance (SPR) sensor for detection of L-phenylalaine by utilizing molecular imprinting technology. l-phenylalanine imprinted and non-imprinted poly(2-hydroxyethyl methacrylate-methacryloyl-l-phenylalanine) polymeric films were synthesized onto SPR chip surfaces using ultraviolet polymerization. l-phenyalanine imprinted and non-imprinted SPR sensors were characterized by using contact angle, atomic force microscopy and ellipsometry. After characterization studies, kinetic studies were carried out in the concentration range of 5.0-400.0 µM. The limit of detection and quantification were obtained as 0.0085 and 0.0285 µM, respectively. The response time for the test including equilibration, adsorption and desorption was approximately 9 min. The selectivity studies of the l-phenylalanine imprinted SPR sensor was performed in the presence of d-phenylalanine and l-tryptophan. Validation studies were carried out via enzyme-linked immunosorbent analysis technique in order to demonstrate the applicability and superiority of the l-phenylalanine imprinted SPR sensor.
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Técnicas Biossensoriais/métodos , Metilmetacrilatos/síntese química , Impressão Molecular/métodos , Fenilalanina/análise , Adsorção , Humanos , Cinética , Limite de Detecção , Metilmetacrilatos/química , Microscopia de Força Atômica , Polímeros , Ressonância de Plasmônio de SuperfícieRESUMO
In this study, surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) sensors were prepared for the detection of amoxicillin from the commercial and local chicken eggs by using molecular imprinting technique. Amoxicillin imprinted poly(hydroxyethyl methacrylate-methacrylic acid) polymeric film was synthesized onto the surface of the SPR and QCM chips by ultra violet polymerization to determine lower concentrations of amoxicillin. Ellipsometry, contact angle analysis, and atomic force microscopy measurements were used for the surface morphology of the polymeric film layer. The ellipsometric thickness of AMOX imprinted and nonimprinted SPR and QCM chip surfaces were measured as 35 ± 0.9 nm, 32.89 ± 1.9 nm, 30 ± 0.6 nm, and 28 ± 0.22 nm, respectively. Contact angles of bare gold surfaces, AMOX imprinted SPR and QCM chip surfaces were measured to be as 82.3° ± 0.15, 79.2° ± 0.14, 75.01° ± 1.07, and 69.11° ± 0.89, respectively. The range of linearity was measured as 0.1 to 10 ng/mL for amoxicillin imprinted SPR and QCM sensors. The maximum residue limit of AMOX in eggs is at 10 µg/kg in accordance with the "Positive List System for Agricultural Chemical Residues in Foods." The response time for the test, including adsorption, desorption, and regeneration, was approximately 45 min. The limit of detections for SPR and QCM sensors were found to be 0.0005 and 0.0023 ng/mL, respectively. The reusabilities of amoxicillin imprinted SPR and QCM sensors were observed by the equilibration-binding-regeneration. Validation studies of the AMOX imprinted SPR and QCM sensors were performed by liquid chromatography-tandem mass spectrometry.
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Amoxicilina/análise , Resíduos de Drogas/análise , Ovos/análise , Contaminação de Alimentos/análise , Ouro/química , Procedimentos Analíticos em Microchip/métodos , Polímeros Molecularmente Impressos/química , Adsorção , Limite de Detecção , Metacrilatos/química , Microscopia de Força Atômica , Impressão Molecular , Poli-Hidroxietil Metacrilato/química , Técnicas de Microbalança de Cristal de Quartzo , Ressonância de Plasmônio de SuperfícieRESUMO
In this study, it is aimed to determine cardiac troponin I by a surface plasmon resonance biosensor immobilized anti-cardiac troponin I monoclonal antibody. The immobilized anti-cardiac troponin I monoclonal antibody surface plasmon resonance biosensors were characterized with ellipsometry, atomic force microscopy and contact angle analysis. After that, surface plasmon resonance biosensor system was completed to biosensor system to investigate kinetic properties for cardiac tropinin I. The sensing ability of surface plasmon resonance biosensor was investigated with 0.001-8.0 ng/mL concentrations of cardiac tropinin I solutions. The limit of detection and limit of quantification were calculated as 0.00012 ng/mL and 0.00041 ng/mL, respectively. To show the selectivity of surface plasmon resonance biosensor competitive adsorption of cardiac tropinin I, myoglobin, immunoglobulin G and prostate specific antigen were investigated. Surface plasmon resonance biosensor was investigated five times with 0.5 ng/mL concentrations of cardiac tropinin I solution to show reuse of the chip. The results showed that surface plasmon resonance biosensor has high selectivity for cardiac tropinin I. The reproducibility of surface plasmon resonance sensors was investigated both on the same day and on different days for five times. To determine the usability, selectivity and validation studies of surface plasmon resonance biosensors were performed by enzyme-linked immunosorbent assay method.
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Técnicas Biossensoriais , Troponina I , Anticorpos Monoclonais , Reprodutibilidade dos Testes , Ressonância de Plasmônio de SuperfícieRESUMO
Molecularly imprinted polymers are used for creating a specific cavity and selective recognition sites for the structure of a target molecule in a polymeric structure. In this study, specific molecularly imprinted cryogel cartridges were synthesized using two distinct functional monomers to compare imprinting efficiency for the selective recognition of Tyrosine (Tyr). Tyr-imprinted cryogel cartridge (MIP1) was prepared using metal-chelate coordination for the imprinting process by free-radical bulk polymerization under frozen conditions, and Tyr-imprinted cryogel cartridge (MIP2) was prepared in the same way using hydrophobic effects for imprinting. After the characterization of the cryogel cartridges was carried out, the optimum adsorption conditions of both were determined according to the different parameters such as flow rate (0.5-2.5 ml/min), pH of the medium (4.0-8.0), initial Tyr concentration (0.1-3.0 mg/ml), and temperature (4-45°C). Selectivity experiments of Tyr-imprinted and non-imprinted cryogel cartridges were carried out by using phenylalanine, tryptophan, and cysteine. Besides, the eluted Tyr from MIP1 and MIP2 cryogel cartridge were applied to FPLC system. Also, the reusability experiments of Tyr-imprinted cryogel cartridges was observed no significant decrease in the adsorption capacity.
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Criogéis/química , Impressão Molecular/métodos , Tirosina/química , Aminoácidos/química , Interações Hidrofóbicas e HidrofílicasRESUMO
A molecularly imprinted polymeric nanofilm was prepared for cocaine detection and applied to plasmonic nanosensor for real-time kinetic, selectivity and reusability analyses. The sensing polymeric surface was fabricated by synthesizing a selective and specific nanofilm on the gold plasmonic nanosensor surface. After characterization experiments with atomic force microscopy, ellipsometer, and contact angle measurements, the kinetic studies of cocaine detection in aqueous solutions in a wide concentration range between 0.2-100 µg/mL were applied to plasmonic nanosensor system at 24 °C with a low limit of detection (0.1 µg/L) and quantification values (0.3 µg/L) and the results showed that this molecularly imprinted polymeric nanofilm integrated plasmonic nanosensor is providing a model for the fastest, most accurate and most precise identification of the cocaine molecule which constitutes a large part of the workload of forensic laboratories.
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Cocaína/análise , Limite de Detecção , Polímeros Molecularmente Impressos/química , Nanotecnologia/instrumentação , Cinética , Água/químicaRESUMO
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).
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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 Saccharomyces cerevisiae. Swelling tests, scanning electron microscopy, surface area measurements and Fourier transform infrared (FTIR) spectroscopy techniques were used for the characterization of dye-affinity cryogel membranes. Following cell homogenization and extraction, MDH was purified using the dye-affinity cryogel membranes at a high yield of 80.5% with 54-fold purification. Maximum MDH adsorption amount was determined to be 267.7 mg/g of membranes at pH 7.4, 25 °C and a flow rate of 1.0 mL/min. Interestingly, the cryogel membranes were used for several purification runs without any significant decrease in MDH adsorption capacity. Sodium dodecyl sulfate polyacrylamide gel electrophoresis was carried out to assess the purity of the eluted MDH. The obtained results highlight the dye-affinity cryogel membranes as powerful dye affinity adsorbents for MDH purification from S. cerevisiae.