The Experts below are selected from a list of 1695 Experts worldwide ranked by ideXlab platform
Adil Denizli - One of the best experts on this subject based on the ideXlab platform.
-
Biomedical Applications of Polymeric Cryogels
MDPI AG, 2019Co-Authors: Monireh Akhshpou, Nesliha Idil, Işık Perçi, Adil DenizliAbstract: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
-
ion imprinted Cryogels for selective removal of ni ii ions from aqueous solutions
Separation and Purification Technology, 2017Co-Authors: Emel Tamahka, Muge Andac, Monireh Akhshpou, Adil DenizliAbstract:Abstract 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.
-
affinity based and molecularly imprinted Cryogels applications in biomacromolecule purification
Journal of Chromatography B, 2016Co-Authors: Muge Andac, Igor Yu Galaev, Adil DenizliAbstract:The publications in macro-molecularly imprinted polymers have increased drastically in recent years with the development of water-based polymer systems. The macroporous structure of Cryogels has allowed the use of these materials within different applications, particularly in affinity purification and molecular imprinting based methods. Due to their high selectivity, specificity, efficient mass transfer and good reproducibility, molecularly imprinted Cryogels (MICs) have become attractive for researchers in the separation and purification of proteins. In this review, the recent developments in affinity based Cryogels and molecularly imprinted Cryogels in protein purification are reviewed comprehensively.
-
hsa immobilized novel polymeric matrix as an alternative sorbent in hemoperfusion columns for bilirubin removal
Reactive & Functional Polymers, 2015Co-Authors: Mahdi Kavoshchian, Serap şenel, Recep Uzek, Sadik Ahmet Uyanik, Adil DenizliAbstract:Abstract HSA immobilized poly(2-hydroxyethylmethacrylate), HSA-P[HEMA], cryogel monolith was examined as an alternative sorbent to be used in hemoperfusion columns for bilirubin removal from serum. The cryogel monolith synthesis was performed by free radical polymerization using MBAA as crosslinker, APS and TEMED as redox pair. Cyanogen bromide (CNBr) was used as a matrix-activating agent for the preparation of immobilized Cryogels. Control cryogel monolith, P[HEMA], and HSA-P[HEMA] were characterized by swelling test, SEM images, porosity and surface area measurements, and blood compatibility tests. Activation and immobilization processes were optimized. The removal of bilirubin from plasma samples overloaded with bilirubin was performed using P[HEMA] cryogel monoliths containing different amounts of immobilized HSA in continuous mode. Several factors affecting adsorption capacity of the matrix such as incubation time, HSA concentration, bilirubin concentration in plasma and temperature were analysed. The maximum bilirubin removal from plasma was 25.4 mg/g at 37.5 °C. The desorption agent was 0.1 M NaOH and 1.0 M NaCl containing solution. The reusability was tested for 10 consecutive adsorption–desorption cycles. The adsorption isotherm models and kinetics of process were also studied.
-
immunoglobulin g purification from bovine serum with pseudo specific supermacroporous Cryogels
Separation and Purification Technology, 2013Co-Authors: Mira Daoudattieh, Lokma Uzu, Haida Chaib, Cana Armutcu, Assem Elkak, Adil DenizliAbstract:Abstract Supermacroporous Cryogels were synthesized and used for the purification of immunoglobulin G (IgG) from bovine serum. Imidazole functional groups were incorporated into basic polymeric backbone to gain pseudo-specificity to Cryogels by using n-vinylimidazole as comonomer. The Cryogels were prepared in aqueous solution of monomers partially frozen inside plastic syringe column by cryogelation. Poly(2-hydroxyethyl methacrylate-n-vinylimidazole) [poly(HEMA-VIM)] Cryogels were prepared by polymerization of water-soluble functional monomer, n-vinylimidazole, with basic monomer HEMA. The characterization methods including swelling test, Fourier transform infrared spectroscopy (FTIR), elemental analysis, and scanning electron microscopy (SEM) were performed to evaluate physical and chemical properties of Cryogels prepared. Bovine IgG adsorption on plain and composite Cryogels was studied with respect to different parameters such as, pH, IgG concentration, flow rate, ionic strengths, and adsorption time. The best adsorption of bovine IgG was observed at pH 7.4 up to 21.1 mg per unit mass of poly(HEMA-VIM) cryogel. Elution of IgG adsorbed from the Cryogels was easily achieved with 0.1 M acetate buffer containing 1 M NaCl at pH 4.0. In order to describe the adsorption process, we applied some equilibrium and kinetic adsorption models to the data. The results best fitted to Langmuir model showing monolayer protein adsorption and surface homogeneity of cryogel. Finally, we evaluated IgG purification from bovine serum under optimal condition determined. The purification efficiency and IgG purity were investigated with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) study.
Fatima M Plieva - One of the best experts on this subject based on the ideXlab platform.
-
removal of heavy metals from water effluents using supermacroporous metal chelating Cryogels
Biotechnology Progress, 2010Co-Authors: Linda Onnby, Fatima M Plieva, Camilla Giorgi, Bo MattiassonAbstract:Applications of IDA in, for example, immobilized metal ion affinity chromatography for purification of His-tagged proteins are well recognized. The use of IDA as an efficient chelating adsorbent for environmental separations, that is, for the capture of heavy metals, is not studied. Adsorbents based on supermacroporous gels (Cryogels) bearing metal chelating functionalities (IDA residues and ligand derived from derivatization of epoxy-cryogel with tris(2-aminoethyl)amine followed by the treatment with bromoacetic acid (defined as TBA ligand)) have been prepared and evaluated on capture of heavy metal ions. The Cryogels were prepared in plastic carriers, resulting in desired mechanical stability and named as macroporous gel particles (MGPs). Sorption and desorption experiments for different metals (Cu²+, Zn²+, Cd²+, and Ni²+ with IDA adsorbent and Cu²+ and Zn²+ with TBA adsorbent) were carried out in batch and monolithic modes, respectively. Obtained capacities with Cu²+ were 74 μmol/mL (TBA) and 19 μmol/mL gel (IDA). The metal removal was higher for pH values between pH 3 and 5. Both adsorbents showed improved sorption at lower temperatures (10°C) than at higher (40°C) and the adsorption significantly dropped for the TBA adsorbent and Zn²+ at 40°C. Desorption of Cu²+ by using 1 M HCl and 0.1 M EDTA was successful for the IDA adsorbent whereas the desorption with the TBA adsorbent needs further attention. The result of this work has demonstrated that MGPs are potential treatment alternatives within the field of environmental separations and the removal of heavy metals from water effluents. (Less)
-
monolithic Cryogels with open porous structure and unique double continuous macroporous networks
Soft Matter, 2008Co-Authors: Fatima M Plieva, Pete Ekstrom, Igor Yu Galaev, O MattiassoAbstract:A novel approach to create macroporous Cryogels (or gels synthesized at sub-zero temperatures) with increased mechanical strength is presented. The Cryogels with unique double-continuous macroporous networks were prepared via sequential freezing–thawing, when the new cryogel was synthesized inside the interconnected macropores of the preformed or primary cryogel. The prepared double-continuous macroporous Cryogels (DM Cryogels) have continuously interlacing networks of primary cryogel with the newly synthesized Cryogels visualized by confocal laser scanning microscopy and scanning electron microscopy. The open structures of the DM Cryogels with up to 150-μm-sized interconnected pores and tissue-like elasticity make them attractive as three-dimensional cell scaffolds for tissue-engineering applications. In particular, a method of preparation of macroporous Cryogels with open porous structure and/or gradient porosity, increased mechanical strength and increased content of functional groups is shown.
-
poly hydroxyethyl methacrylate based macroporous hydrogels with disulfide cross linker
Macromolecular Chemistry and Physics, 2008Co-Authors: Muge Andac, Adil Denizli, Fatima M Plieva, Yu I Galaev, Bo MattiassonAbstract:Biodegradable supermacroporous PHEMA Cryogels were produced by combining two cross-linkers, poly(ethylene glycol) diacrylate and a newly developed disulfide water soluble crosslinker, N,N'-bis(methacryloyl)-L-cystine. The biodegradable PHEMA Cryogels were prepared with gel fraction yields up to 70% and were characterized by highly interconnected pores of micrometer size and good mechanical stability. When subjected to reductive agents like DTT, the biodegradable PHEMA Cryogels disintegrated into small pieces. The rate of disintegration was controlled by the crosslinking density in the Cryogels and the DTT concentration.
-
pore structure in supermacroporous polyacrylamide based Cryogels
Journal of Materials Chemistry, 2005Co-Authors: Fatima M Plieva, Sergey V Mikhalovsky, Mali Karlsso, Maria Rosa Aguila, David Gomez, Igor Yu GalaevAbstract:Pore size and thickness of pore walls in macroporous polyacrylamide gels, so-called Cryogels (pAAm-Cryogels), were controlled by varying the content of monomers in the initial reaction mixture and the cross-linker used. The thickness of pore walls in pAAm-Cryogels increased with increasing concentration of monomers in the initial reaction mixture. Pore volume in the supermacroporous pAAm-Cryogels was in the range of 70-93% and decreased with increasing concentration of monomers in the reaction feed. The porous structure of the pAAm-Cryogels was visualized using environmental scanning electron microscopy (ESEM) that allowed monitoring of the dehydration process in pAAm-Cryogels. The accessibility of ligands covalently coupled to the polymer backbone for low molecular weight target, Cu(II) ions, and high molecular weight target, the protein lysozyme, was assessed for pAAm-Cryogels produced from feeds with different monomer concentration. The amount of bound Cu(II) ions increased linearly with increasing monomer concentration in the reaction feed, suggesting that all ligands are equally accessible for small targets. On the contrary, lysozyme binding demonstrated a clear maximum at monomer concentration about 18% suggesting that only ligands present at the surface of pore walls are accessible for high molecular weight targets.
-
integrated isolation of antibody fragments from microbial cell culture fluids using supermacroporous Cryogels
Journal of Chromatography A, 2004Co-Authors: Maria Dainiak, Fatima M Plieva, Igor Yu Galaev, Ashok Kuma, O MattiassoAbstract:The present paper describes a chromatographic capture/purification step for the recovery of proteins directly from undiluted and unclarified cell culture broths using supermacroporous dimethylacrylamide (DMAA) cryogel. The interconnected character and the size (10-100 microm) of the pores of the adsorbent make it possible to process whole cell fermentation broths without blocking the column. Cu2+-iminodiacetic acid (IDA) DMAA cryogel has been used for the isolation and purification of excreted (His)6-tagged single chain (sc) Fv antibody fragments, (His)6-scFv, from E. coli cell culture. Bound protein was recovered with 0.2 M imidazole or with 20 mM EDTA and was practically cell-free. Chromatographic capture using Cu2+-IDA cryogel column was performed at flow rates of 300 and 600 cm/h, respectively and resulted in 84-96% recovery of (His)6-scFv fragments with a purification factor of 13-15. The DMAA cryogel adsorbent is mechanically stable, can withstand harsh cleaning-in-place procedure and is relatively inexpensive. Chromatographic isolation of proteins using Cryogels allows efficient removal of cells and can be operated at a flow rate as high as 600 cm/h. This novel technique has proven to be a scalable process, does not require special equipment and can be a good alternative to expanded bed adsorption and other integrated isolation techniques.
Igor Yu Galaev - One of the best experts on this subject based on the ideXlab platform.
-
affinity based and molecularly imprinted Cryogels applications in biomacromolecule purification
Journal of Chromatography B, 2016Co-Authors: Muge Andac, Igor Yu Galaev, Adil DenizliAbstract:The publications in macro-molecularly imprinted polymers have increased drastically in recent years with the development of water-based polymer systems. The macroporous structure of Cryogels has allowed the use of these materials within different applications, particularly in affinity purification and molecular imprinting based methods. Due to their high selectivity, specificity, efficient mass transfer and good reproducibility, molecularly imprinted Cryogels (MICs) have become attractive for researchers in the separation and purification of proteins. In this review, the recent developments in affinity based Cryogels and molecularly imprinted Cryogels in protein purification are reviewed comprehensively.
-
bilirubin recognition via molecularly imprinted supermacroporous Cryogels
Colloids and Surfaces B: Biointerfaces, 2009Co-Authors: Gozde Aydemi, Igor Yu Galaev, Nilay Ereli, Ridva Say, Muge Andac, Adil DenizliAbstract:Recent years molecular imprinting has received considerable attention as an excellent and simple approach to recognize small molecules and bioactive substances. The aim of this study is to prepare the bilirubin-imprinted supermacroporous Cryogels which can be used for the adsorption of bilirubin from human plasma. N-methacryloyl-(L)-tyrosinemethylester (MAT) was chosen as the pre-organization monomer. In the first step, bilirubin was complexed with MAT and the bilirubin-imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-tyrosine methylester) [BR-MIP] cryogel was produced by free radical polymerization initiated by N,N,N',N'-tetramethylene diamine (TEMED) and ammonium persulfate (APS) pair in an ice bath. After that, the template molecules (i.e., bilirubin) were removed from the polymeric structure using sodium carbonate and sodium hydroxide. The maximum bilirubin adsorption amount was 3.6 mg/g polymer. The relative selectivity coefficients of the BR-MIP cryogel for bilirubin/cholesterol and bilirubin/testosterone mixtures were 7.3 and 3.2 times greater than non-imprinted poly(HEMA-MAT) [NIP] cryogel, respectively. The BR-MIP cryogel could be used many times without decreasing bilirubin adsorption amount significantly. Therefore, as a reusable carrier possessing high selectivity, BR-MIP cryogel has a potential candidate as a clinical hemoperfusion material.
-
monolithic Cryogels with open porous structure and unique double continuous macroporous networks
Soft Matter, 2008Co-Authors: Fatima M Plieva, Pete Ekstrom, Igor Yu Galaev, O MattiassoAbstract:A novel approach to create macroporous Cryogels (or gels synthesized at sub-zero temperatures) with increased mechanical strength is presented. The Cryogels with unique double-continuous macroporous networks were prepared via sequential freezing–thawing, when the new cryogel was synthesized inside the interconnected macropores of the preformed or primary cryogel. The prepared double-continuous macroporous Cryogels (DM Cryogels) have continuously interlacing networks of primary cryogel with the newly synthesized Cryogels visualized by confocal laser scanning microscopy and scanning electron microscopy. The open structures of the DM Cryogels with up to 150-μm-sized interconnected pores and tissue-like elasticity make them attractive as three-dimensional cell scaffolds for tissue-engineering applications. In particular, a method of preparation of macroporous Cryogels with open porous structure and/or gradient porosity, increased mechanical strength and increased content of functional groups is shown.
-
protein recognition via ion coordinated molecularly imprinted supermacroporous Cryogels
Journal of Chromatography A, 2008Co-Authors: Nilay Ereli, Igor Yu Galaev, Ridva Say, Gozde Aydemi, Muge Andac, Adil DenizliAbstract:Molecular imprinting is a method for making selective binding sites in synthetic polymers using a molecular template. The aim of this study is to prepare lysozyme-imprinted supermacroporous Cryogels which can be used for the purification of lysozyme (Lyz) from egg white. N-Methacryloyl-(L)-histiclinemethylester (MAH) was chosen as the metal-coordinating monomer. In the first step, Cu2+ was complexed with MAH and the lysozyme-imprinted poly(HEMA-MAH) [Lyz-MIP] cryogel were produced by free radical polymerization initiated by N,N,N',N'-tetramethylene diamine (TEMED) in an ice bath. After that, the template (i.e., lysozyme) was removed using 0.05 M phosphate buffer containing 1 M NaCl (pH 8.0). The maximum lysozyme adsorption capacity was 22.9 mg/g polymer. The relative selectivity coefficients of Lyz-MIP cryogel for lysozyme/bovine serum albumin and lysozyme/cytochrome c were 4.6 and 3.2 times greater than non-imprinted poly(HEMA-MAH) (NIP) cryogel, respectively. Purification of lysozyme from egg white was also monitored by determining the lysozyme activity using Micrococcus lysodeikticus as substrate. The purity of the desorbed lysozyme was about 94% with recovery about 86%. The Lyz-MIP cryogel could be used many times without decreasing the adsorption capacity significantly. (Less)
-
pore structure in supermacroporous polyacrylamide based Cryogels
Journal of Materials Chemistry, 2005Co-Authors: Fatima M Plieva, Sergey V Mikhalovsky, Mali Karlsso, Maria Rosa Aguila, David Gomez, Igor Yu GalaevAbstract:Pore size and thickness of pore walls in macroporous polyacrylamide gels, so-called Cryogels (pAAm-Cryogels), were controlled by varying the content of monomers in the initial reaction mixture and the cross-linker used. The thickness of pore walls in pAAm-Cryogels increased with increasing concentration of monomers in the initial reaction mixture. Pore volume in the supermacroporous pAAm-Cryogels was in the range of 70-93% and decreased with increasing concentration of monomers in the reaction feed. The porous structure of the pAAm-Cryogels was visualized using environmental scanning electron microscopy (ESEM) that allowed monitoring of the dehydration process in pAAm-Cryogels. The accessibility of ligands covalently coupled to the polymer backbone for low molecular weight target, Cu(II) ions, and high molecular weight target, the protein lysozyme, was assessed for pAAm-Cryogels produced from feeds with different monomer concentration. The amount of bound Cu(II) ions increased linearly with increasing monomer concentration in the reaction feed, suggesting that all ligands are equally accessible for small targets. On the contrary, lysozyme binding demonstrated a clear maximum at monomer concentration about 18% suggesting that only ligands present at the surface of pore walls are accessible for high molecular weight targets.
Bo Mattiasson - One of the best experts on this subject based on the ideXlab platform.
-
chemically modified poly 2 hydroxyethyl methacrylate cryogel for the adsorption of heparin
Journal of Biomedical Materials Research Part B, 2014Co-Authors: R La Spina, Carla Tripisciano, Tommaso Mecca, F Cunsolo, Viktoria Weber, Bo MattiassonAbstract:Various clinical procedures, such as cardiovascular surgery or extracorporeal blood purification, involve systemic anticoagulation using heparin. High concentrations of circulating heparin require neutralization due to possible serious bleeding complications. The intravenous administration of the heparin antagonist protamine sulfate is routinely clinically performed, but is frequently associated with adverse reactions. Therefore, there is a need for a valid and safe alternative to achieve extracorporeal heparin removal from blood or plasma, such as a filter, a matrix, or an adsorbent. Here, we describe the development of a macroporous poly(2-hydroxyethyl methacrylate)-based monolithic cryogel functionalized with l-lysine (pHEMA-lys) and the characterization of its selective heparin adsorption. The maximum binding capacity was quantified in vitro using aqueous and serum solutions under static and dynamic conditions, and fresh human plasma under static conditions. The pHEMA-lys bound 40,500 IU and 32,500 IU heparin/g cryogel at the equilibrium in aqueous solution and 50% serum, respectively. In human plasma spiked with 100 IU/mL of heparin, the binding was still highly efficient (4330 IU/g cryogel after 30 min, i.e., 87% of the initial concentration). The Cryogels showed good blood compatibility, as indicated by negligible adsorption of albumin, antithrombin III, and total protein, and may thus be suitable for extracorporeal heparin removal. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2014. (Less)
-
removal of heavy metals from water effluents using supermacroporous metal chelating Cryogels
Biotechnology Progress, 2010Co-Authors: Linda Onnby, Fatima M Plieva, Camilla Giorgi, Bo MattiassonAbstract:Applications of IDA in, for example, immobilized metal ion affinity chromatography for purification of His-tagged proteins are well recognized. The use of IDA as an efficient chelating adsorbent for environmental separations, that is, for the capture of heavy metals, is not studied. Adsorbents based on supermacroporous gels (Cryogels) bearing metal chelating functionalities (IDA residues and ligand derived from derivatization of epoxy-cryogel with tris(2-aminoethyl)amine followed by the treatment with bromoacetic acid (defined as TBA ligand)) have been prepared and evaluated on capture of heavy metal ions. The Cryogels were prepared in plastic carriers, resulting in desired mechanical stability and named as macroporous gel particles (MGPs). Sorption and desorption experiments for different metals (Cu²+, Zn²+, Cd²+, and Ni²+ with IDA adsorbent and Cu²+ and Zn²+ with TBA adsorbent) were carried out in batch and monolithic modes, respectively. Obtained capacities with Cu²+ were 74 μmol/mL (TBA) and 19 μmol/mL gel (IDA). The metal removal was higher for pH values between pH 3 and 5. Both adsorbents showed improved sorption at lower temperatures (10°C) than at higher (40°C) and the adsorption significantly dropped for the TBA adsorbent and Zn²+ at 40°C. Desorption of Cu²+ by using 1 M HCl and 0.1 M EDTA was successful for the IDA adsorbent whereas the desorption with the TBA adsorbent needs further attention. The result of this work has demonstrated that MGPs are potential treatment alternatives within the field of environmental separations and the removal of heavy metals from water effluents. (Less)
-
poly hydroxyethyl methacrylate based macroporous hydrogels with disulfide cross linker
Macromolecular Chemistry and Physics, 2008Co-Authors: Muge Andac, Adil Denizli, Fatima M Plieva, Yu I Galaev, Bo MattiassonAbstract:Biodegradable supermacroporous PHEMA Cryogels were produced by combining two cross-linkers, poly(ethylene glycol) diacrylate and a newly developed disulfide water soluble crosslinker, N,N'-bis(methacryloyl)-L-cystine. The biodegradable PHEMA Cryogels were prepared with gel fraction yields up to 70% and were characterized by highly interconnected pores of micrometer size and good mechanical stability. When subjected to reductive agents like DTT, the biodegradable PHEMA Cryogels disintegrated into small pieces. The rate of disintegration was controlled by the crosslinking density in the Cryogels and the DTT concentration.
-
affinity binding of inclusion bodies on supermacroporous monolithic Cryogels using labeling with specific antibodies
Journal of Biotechnology, 2006Co-Authors: Josefin Ahlqvist, Ashok Kumar, Helene Sundstrom, Erika Ledung, E G Hornsten, S O Enfors, Bo MattiassonAbstract:A new chromatographic method based on affinity supermacroporous monolithic Cryogels is developed for binding and analyzing inclusion bodies during fermentation. The work demonstrated that it is possible to bind specific IgG and IgY antibodies to the 15 and 17 amino acids at the terminus ends of a 33 kDa target protein aggregated as inclusion bodies. The antibody treated inclusion bodies from lysed fermentation broth can be specifically retained in protein A and pseudo-biospecific ligand sulfamethazine modified supermacroporous Cryogels. The degree of binding of IgG and IgY treated inclusion bodies to the Protein A and sulfamethazine gels are investigated, as well as the influence of pH on the sulfamethazine ligand. Optimum binding of 78 and 72% was observed on both protein A and sulfamethazine modified cryogel columns, respectively, using IgG labeling of the inclusion bodies. The antibody treated inclusion bodies pass through unretained in the sulfamethazine supermacroporous gel at pH that does not favour the binding between the ligand on the gel and the antibodies on the surface of inclusion bodies. Also the unlabeled inclusion bodies went through the gel unretained, showing no non-specific binding or trapping within the gel. These findings may very well be the foundation for the building of a powerful analytical tool during fermentation of inclusion bodies as well as a convenient way to purify them from fermentation broth. These results also support our earlier findings [Kumar, A., Plieva, F.M., Galaev, I.Yu., Mattiasson, B.. 2003. Affinity fractionation of lymphocytes using a monolithic cyogel. J. Immunol. Methods 283, 185-194] with mammalian cells that were surface labeled with specific antibodies and recognized on protein A supermacroporous gels. A general binding and separation system can be established on antibody binding cryogel affinity matrices.
Nathaniel S Hwang - One of the best experts on this subject based on the ideXlab platform.
-
gelatin based extracellular matrix Cryogels for cartilage tissue engineering
Journal of Industrial and Engineering Chemistry, 2017Co-Authors: Yung Jae Kang, Suhwa Kim, Hwa Kim, Nathaniel S HwangAbstract:Abstract In this study, gelatin-based Cryogels were fabricated by mixing methacrylated gelatin (GelMA) with methacrylated hyaluronic acid (MeHA) or methacrylated chondroitin sulfate (MeCS) for cartilage tissue engineering. In vitro revealed that MeCS incorporated gelatin-based cryogel (G-MeCS) showed significant cartilaginous tissue stimulation. Furthermore, the cell-laden gelatin-based ECM Cryogels were implanted into mouse subcutaneous tissue for 6 weeks and displayed uniform distribution of cells with normal phenotype maintenance. Finally, when these Cryogels were implanted into osteochondral defect of New Zealand white rabbit, full integration with host tissue and increased cellularity were observed with G-MeCS cryogel.
-
extracellular matrix based Cryogels for cartilage tissue engineering
International Journal of Biological Macromolecules, 2016Co-Authors: Suhwa Kim, Sidi A Encherif, Hwa Kim, Hyungu Yim, Taeil Kim, Nathaniel S HwangAbstract:In this study, we investigated various highly porous extracellular matrix (ECM)-based Cryogels for cartilage tissue engineering. For the fabrication of ECM-based Cryogels, either methacrylated chondroitin sulfate (MeCS) or methacrylated hyaluronic acid (MeHA) were cross-linked along with poly (ethylene glycol) diacrylates (PEGDA) via free radical polymerization under freezing conditions. This procedure induces ice crystallization (used as a porogen) prior polymer crosslinking in which, after complete cryopolymerization, a thawing process transforms the ice crystals into a unique interconnected macroporous structure within ECM-Cryogels. The developed ECM-Cryogels exhibited an average macroporosity of 75% and supported the infiltration of chondrocyteds. When rabbit chondrocytes were cultured on ECM-Cryogels, MeCS-based Cryogels stimulated aggrecan gene expression and GAG accumulation, whereas MeHA-based Cryogels stimulated type II collagen gene expression and collagen accumulation. These results demonstrate that design of ECM-based Cryogels can play an important role in promoting specific ECM proteins secretion for cartilage tissue engineering.