Investigation of the activation of various insoluble polysaccharides with 1,1′-carbonyldiimidazole and of the properties of the activated matrices

Bethell, G.S.; Ayers, John S.; Hearn, Milton Thomas William; Hancock, William S.

doi:10.1016/s0021-9673(00)80379-9

Cited by 63 publications

(6 citation statements)

References 15 publications

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“…No leakage of DFO or its breakdown products from the dressing was detected. This is in line with data from the literature on the extraordinary stability of urethane bonds (Bethell and Ayers, 1981).…”

Section: Discussionsupporting

confidence: 92%

Selective Pick-Up of Increased Iron by Deferoxamine-Coupled Cellulose Abrogates the Iron-Driven Induction of Matrix-Degrading Metalloproteinase 1 and Lipid Peroxidation in Human Dermal Fibroblasts In Vitro: A New Dressing Concept

Wenk¹,

Foitzik

Achterberg

et al. 2001

Journal of Investigative Dermatology

102

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Using atomic absorption spectrum analysis, we found iron levels in exudates from chronic wounds to be significantly increased (3.71 +/- 1.56 micromol per g protein) compared to wound fluids from acute wounds derived from blister fluids (1.15 +/- 0.62 micromol per g protein, p < 0.02), drainage fluids of acute wounds (0.87 +/- 0.34 micromol per g protein, p < 0.002), and pooled human plasma of 50 volunteers (0.42 micromol per g protein). Increased free iron and an increase in reactive oxygen species released from neutrophils represent pathogenic key steps that --via the Fenton reaction - are thought to be responsible for the persistent inflammation, increased connective tissue degradation, and lipid peroxidation contributing to the prooxidant hostile microenvironment of chronic venous leg ulcers. We herein designed a selective pick-up dressing for iron ions by covalently binding deferoxamine to cellulose. No leakage occurred following gamma sterilization of the dressing and, more importantly, the deferoxamine-coupled cellulose dressing retained its iron complexing properties sufficient to reduce iron levels found in chronic venous ulcers to levels comparable to those found in acute wounds. In order to study the functionality of the dressing, human dermal fibroblasts were exposed to a Fenton reaction mimicking combination of 220 microM Fe(III) citrate and 1 mM ascorbate resulting in a 4-fold induction of matrix-degrading metalloproteinase 1 as determined by a matrix-degrading metalloproteinase 1 specific enzyme-linked immunosorbent assay. This induction was completely suppressed by dissolved deferoxamine at a concentration of 220 microM or by an equimolar amount of deferoxamine immobilized to cellulose. In addition, the Fe(III) citrate and ascorbate driven Fenton reaction resulted in an 8-fold increase in malondialdehyde, the major product of lipid peroxidation, as determined by high pressure liquid chromatography. This increase in malondialdehyde levels could be significantly reduced in the presence of the selective pick-up dressing coupled with deferoxamine suggesting that the deferoxamine dressing, in fact, prevents the development of a damaging prooxidant microenvironment and also protects from unfavorable consequences like matrix-degrading metalloproteinase 1 and lipid peroxide induction.

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Section: Discussionsupporting

confidence: 92%

Selective Pick-Up of Increased Iron by Deferoxamine-Coupled Cellulose Abrogates the Iron-Driven Induction of Matrix-Degrading Metalloproteinase 1 and Lipid Peroxidation in Human Dermal Fibroblasts In Vitro: A New Dressing Concept

Wenk¹,

Foitzik

Achterberg

et al. 2001

Journal of Investigative Dermatology

102

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“…The CDI-aminocaproic acid chemistry had three disadvantages: anhydrous solvation requirement, labile chemical bonds and expensive carbodiimides. Urethane and amide bonds are slowly hydrolyzed at high pH (Bethell et al, 1981;McMurray, 1988). Therefore, regeneration of a matrix using 0.1 M NaOH could result in ligand leaching.…”

Section: Ligand-substituted CM Matricesmentioning

confidence: 99%

One step purification of chymosin by mixed mode chromatography

Burton¹,

Haggarty²,

Harding³

1997

Biotechnol. Bioeng.

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Mixed mode Sepharose and Perloza bead cellulose matrices were prepared using various chemistries. These matrices contained hydrophobic (aliphatic and/or aromatic) and ionic (carboxylate or alkylamine) groups. Hydrophobic amine ligands were attached to epichlorohydrin activated Sepharose (mixed mode amine matrices). Hexylamine, aminophenylpropanediol and phenylethylamine were the preferred ligands, on the basis of cost and performance. Other mixed mode matrices were produced by incomplete attachment (0-80%) of the same amine ligands to carboxylate matrices. The best results were obtained using unmodified or partially ligandmodified aminocaproic acid Sepharose and Perloza. High ligand densities were used, resulting in high capacity. Furthermore, chymosin was adsorbed at high and low ionic strengths, which reduced sample preparation requirements. Chymosin, essentially homogeneous by electrophoresis, was recovered by a small pH change. The methods described were simple, efficient, inexpensive and provided very good resolution of chymosin from a crude recombinant source. The carboxylate matrices had the best combination of capacity and regeneration properties. The performance of Sepharose and Perloza carboxylate matrices was similar, but higher capacities were found for the latter. Because it is cheaper and can be used at higher flow rates, Perloza should be better suited to large scale application. High capacity chymosin adsorption was found with carboxymethyl ion exchange matrices, but low ionic strength was essential for adsorption and the purity was inferior to that of the mixed mode matrices.

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“…This mixture was shaken for 3–4 h at room temperature, followed by washing with dioxane, and this activated sepharose gel was used immediately. It should be noted, that in the whole washing process, a Buchner funnel for separating sepharose from the solvent was used. , …”

Section: Experimental Sectionmentioning

confidence: 99%

“…It should be noted, that in the whole washing process, a Buchner funnel for separating sepharose from the solvent was used. 50,51 Conjugation of APES−Fe 3 O 4 on the Resin Surface (APES−MNPs−Resin). To immobilize APES−Fe 3 O 4 , the activated sepharose gel was suspended in a sodium carbonate buffer (pH 9.7), and 50 mg of APES−Fe 3 O 4 was added to this solution, followed by incubation at 25 °C for l6 h. 51 Synthesis of Mono-6-(p-toluenesulfonyl)-deoxy-6-cyclodextrin (Ts-β-CD).…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

β-Cyclodextrin-Modified Magnetic Nanoparticles Immobilized on Sepharose Surface Provide an Effective Matrix for Protein Refolding

et al. 2018

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In this article, we propose an impressive and facile strategy to improve protein refolding using solid phase artificial molecular chaperones consisting of the surface-functionalized magnetic nanoparticles. Specifically, monotosyl-β-cyclodextrin connected to the surface of 3-aminopropyltriethoxysilane (APES)-modified magnetic nanoparticles is immobilized on the sepharose surface to promote interaction with exposed hydrophobic surfaces of partially folded (intermediates) and unfolded states of proteins. Their efficiencies were investigated by circular dichroism spectroscopy and photoluminescence spectroscopy of the protein. Although the mechanism of this method is based on principles of hydrophobic chromatography, this system is not only purging the native protein from inactive inclusion bodies but also improving the protein refolding process. We chose β-cyclodextrin (β-CD) considering multiple reports in the literature about its efficiency in protein refolding and its biocompatibility. To increase the surface area/volume ratio of the sepharose surface by nanoparticles, more β-CD molecules are connected to the sepharose surface to make a better interaction with proteins. We suppose that proteins are isolated in the nanospace created by bound cyclodextrins on the resin surface so intermolecular interactions are reduced. The architecture of nanoparticles was characterized by Fourier transform infrared spectra, X-ray diffraction, scanning electron microscopy images, energy dispersive X-ray spectroscopy, nuclear magnetic resonance (1H NMR and 13C NMR), and dynamic light scattering.

show abstract

Investigation of the activation of various insoluble polysaccharides with 1,1′-carbonyldiimidazole and of the properties of the activated matrices

Cited by 63 publications

References 15 publications

Selective Pick-Up of Increased Iron by Deferoxamine-Coupled Cellulose Abrogates the Iron-Driven Induction of Matrix-Degrading Metalloproteinase 1 and Lipid Peroxidation in Human Dermal Fibroblasts In Vitro: A New Dressing Concept

Selective Pick-Up of Increased Iron by Deferoxamine-Coupled Cellulose Abrogates the Iron-Driven Induction of Matrix-Degrading Metalloproteinase 1 and Lipid Peroxidation in Human Dermal Fibroblasts In Vitro: A New Dressing Concept

One step purification of chymosin by mixed mode chromatography

β-Cyclodextrin-Modified Magnetic Nanoparticles Immobilized on Sepharose Surface Provide an Effective Matrix for Protein Refolding

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