A Cross-Linker Free Enzyme Immobilization for Direct Bioelectrocatalysis Using Aqueous Phase Inversion of a High-Ionic-Strength, Liquid Complex Coacervate

The properties of the clay bentonite as a support for enzyme immobilization were studied using the enzyme catalase. Such an immobilization does not result in enzyme inactivation and constitutes a valuable method for immobilizing catalase at high ionic strength. The bentonite-supported catalase was characterized in terms of pH and ionic strength dependencies, thermal and storage stability and kinetic parameters. These studies indicate that bentonite is a valuable support for the simple adsorption of enzymes. .

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Tuning the Interactions in Multiresponsive Complex Coacervate-Based Underwater Adhesives

International Journal of Molecular Sciences ◽

10.3390/ijms21010100 ◽

2019 ◽

Vol 21 (1) ◽

pp. 100 ◽

Cited By ~ 4

Author(s):

Marco Dompé ◽

Francisco J. Cedano-Serrano ◽

Mehdi Vahdati ◽

Ugo Sidoli ◽

Olaf Heckert ◽

...

Keyword(s):

Ionic Strength ◽

Adhesive System ◽

Systematic Investigation ◽

High Ionic Strength ◽

Work Of Adhesion ◽

Polymer Composition ◽

Adhesive Properties ◽

Preparation Conditions ◽

Complex Coacervate ◽

Non Covalent Interactions

In this work, we report the systematic investigation of a multiresponsive complex coacervate-based underwater adhesive, obtained by combining polyelectrolyte domains and thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) units. This material exhibits a transition from liquid to solid but, differently from most reactive glues, is completely held together by non-covalent interactions, i.e., electrostatic and hydrophobic. Because the solidification results in a kinetically trapped morphology, the final mechanical properties strongly depend on the preparation conditions and on the surrounding environment. A systematic study is performed to assess the effect of ionic strength and of PNIPAM content on the thermal, rheological and adhesive properties. This study enables the optimization of polymer composition and environmental conditions for this underwater adhesive system. The best performance with a work of adhesion of 6.5 J/m2 was found for the complex coacervates prepared at high ionic strength (0.75 M NaCl) and at an optimal PNIPAM content around 30% mol/mol. The high ionic strength enables injectability, while the hydrated PNIPAM domains provide additional dissipation, without softening the material so much that it becomes too weak to resist detaching stress.

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Separation of nucleobases and their derivatives with organic-high ionic strength aqueous phase systems by spiral high-speed counter-current chromatography

Journal of Chromatography B ◽

10.1016/j.jchromb.2012.02.012 ◽

2012 ◽

Vol 891-892 ◽

pp. 94-97 ◽

Cited By ~ 11

Author(s):

Yoichi Shibusawa ◽

Akio Yanagida ◽

Atsushi Ogihara ◽

Ying Ma ◽

Xiaoyuan Chen ◽

...

Keyword(s):

Ionic Strength ◽

Aqueous Phase ◽

High Speed ◽

High Ionic Strength ◽

Phase Systems ◽

Counter Current

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The distribution of blood-group antigens on butanol extraction of human erythrocyte ‘ghosts’

Biochemical Journal ◽

10.1042/bj1380381 ◽

1974 ◽

Vol 138 (3) ◽

pp. 381-386 ◽

Cited By ~ 37

Author(s):

D. J. Anstee ◽

M. J. A. Tanner

Keyword(s):

Ionic Strength ◽

Blood Group ◽

Aqueous Phase ◽

High Ionic Strength ◽

High Yield ◽

Erythrocyte Ghosts ◽

Blood Group A ◽

Butanol Extraction ◽

Group A ◽

Blood Group P

The distribution of protein and blood-group-antigen activity obtained after butanol extraction of erythrocyte `ghosts' under various conditions is described. Butanol extraction under low-ionic strength conditions results in the recovery of membrane protein in high yield in the aqueous phase. Blood-group-A activity is found in both the aqueous and butanol phases, whereas blood-group-P activity is confined to the butanol phase and blood-group-I and blood-group-MN activity are restricted to the aqueous phase. Much lower yields of protein are obtained in the aqueous phase when high-ionic-strength conditions are used. An appreciable amount of material is precipitated at the interface. Under these conditions blood-group-P activity is found only in the butanol phase, blood group-A activity in the butanol phase and interface material and only blood-group-MN activity in the aqueous phase. In contrast with previous reports no correlation could be demonstrated between the secretor status of the donors and the presence of blood-group-A activity in the aqueous phase after butanol extraction under any of the extraction conditions used. By using butanol extraction under high-ionic-strength conditions it is possible to isolate the blood-group-MN-active sialoglycoprotein in high yield from erythrocyte `ghosts' by a simple procedure.

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Importance of Protease Inhibition in Studies on Purified Factor VIII (Antihaemophilic Factor)

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647943 ◽

1976 ◽

Vol 35 (01) ◽

pp. 186-190 ◽

Cited By ~ 6

Author(s):

Eugen A. Beck ◽

Peter Bachmann ◽

Peter Barbier ◽

Miha Furlan

Keyword(s):

Ionic Strength ◽

Factor Viii ◽

Gel Filtration ◽

High Ionic Strength ◽

Procoagulant Activity ◽

Carrier Protein ◽

Protease Inhibition ◽

Functional Sites ◽

Molecular Weight Peak ◽

Von Willebrand

SummaryAccording to some authors factor VIII procoagulant activity may be dissociable from carrier protein (MW~ 2 × 106) by agarose gel filtration, e.g. at high ionic strength. We were able to reproduce this phenomenon. However, addition of protease inhibitor (Trasylol) prevented the appearance of low molecular weight peak of factor VIII procoagulant activity both at high ionic strength and elevated temperature (37°C). We conclude from our results that procoagulant activity and carrier protein (von Willebrand factor, factor VIII antigen) are closely associated functional sites of native factor VIII macro molecule. Consequently, proteolytic degradation should be avoided in functional and structural studies on factor VIII and especially in preparing factor VIII concentrate for therapeutic use.

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THE RELATIVE DISTRIBUTION OF THYROXINE, TRIIODOTHYRONINE AND 3,3′,5′-(REVERSE)-TRIIODOTHYRONINE IN VARIOUS FRACTIONS OF THYROGLOBULIN

Acta Endocrinologica ◽

10.1530/acta.0.0880298 ◽

1978 ◽

Vol 88 (2) ◽

pp. 298-305 ◽

Cited By ~ 2

Author(s):

Peter Laurberg

Keyword(s):

Ionic Strength ◽

Guinea Pig ◽

Sucrose Gradient ◽

Deae Cellulose ◽

High Ionic Strength ◽

Relative Distribution ◽

Thyroid Extract ◽

Reverse Triiodothyronine ◽

Thyroid Secretion ◽

Stable Iodine

ABSTRACT Thyroglobulin fractions rich and poor in new thyroglobulin were separated by means of DEAE-cellulose chromatography of dog thyroid extracts and by zonal ultracentrifugation in a sucrose gradient of guinea pig thyroid extract incubated at low temperature. The distribution of thyroxine, triiodothyronine and 3,3′,5′-(reverse)-triiodothyronine in hydrolysates of the different fractions was estimated by radioimmunoassays. Following DEAE-cellulose chromatography there was a small but statistically significant increase in the T4/T3 ratio in thyroglobulin fractions eluted at high ionic strength - that is fractions relatively rich in stable iodine but poor in fresh thyroglobulin. There were no differences in the T4/rT3 ratios between the different fractions. The ratios between iodothyronines were almost identical in the various thyroglobulin fractions following zonal ultracentrifugation in a sucrose gradient of cold treated guinea pig thyroid extract. These findings lend no support to the possibility that a relatively high content of triiodothyronines in freshly synthesized thyroglobulin modulates the thyroid secretion towards a preferential secretion of triiodothyronine and 3,3′,5′-(reverse)-triiodothyronine at the expense of the secretion of thyroxine.

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Extraction of hafnium(IV) with organophosphorus reagents from solutions of mineral acids mixtures

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19793656 ◽

1979 ◽

Vol 44 (12) ◽

pp. 3656-3664

Author(s):

Oldřich Navrátil ◽

Jiří Smola ◽

Rostislav Kolouch

Keyword(s):

Ionic Strength ◽

Aqueous Phase ◽

Organic Phase ◽

Perchloric Acid ◽

Synergic Effect ◽

Salting Out ◽

Initial Concentration ◽

Mixed Complexes ◽

Synergic Extraction ◽

Mineral Acids

Extraction of hafnium(IV) was studied from solutions of mixtures of perchloric and nitric acids and of perchloric and hydrochloric acids for constant ionic strength, I = 2, 4, 6, or 8, and for cHf 4 . 10-4 mol l-1. The organic phase was constituted by solutions of some acidic or neutral organophosphorus reagents or of 2-thenoyltrifluoroacetone, 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone, or N-benzoyl-N-phenylhydroxylamine in benzene, chloroform, or n-octane. A pronounced synergic extraction of hafnium proceeds only on applying organophosphorus reagents from an aqueous phase whose acidity is not lower than 3M-(HClO4 + HNO3) or 5M-(HClO4 + HCl). The synergic effect was not affected markedly by a variation of the initial concentration of hafnium in the range 1 . 10-8 -4 .10-4 mol l-1, it lowered with increasing initial concentration of the organophosphorus reagent and decreasing concentration of the H+ ions. It is suggested that the hafnium passes into the organic phase in the form of mixed complexes, the salting-out effect of perchloric acid playing an appreciable part.

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Extraction of hafnium by means of some substituted 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-ones

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811901 ◽

1981 ◽

Vol 46 (8) ◽

pp. 1901-1905 ◽

Cited By ~ 3

Author(s):

Oldřich Navrátil ◽

Jiří Smola

Keyword(s):

Ionic Strength ◽

Aqueous Phase ◽

Dissociation Constants ◽

Parent Substance ◽

Benzoyl Group ◽

Extraction Constants ◽

Extraction Parameters ◽

Substituted 1

Distribution between aqueous phase and benzene or chloroform was studied for 1-phenyl-3-methyl-4-benzoylpyrazol-5-ones with 2-chloro, 4-methoxy, 3-nitro, and 4-nitro substitution in the benzoyl group (ionic strength of the aqueous phase 0.1) and for hafnium in their presence (ionic strength 2.0). The distribution and dissociation constants of the reagents and the extraction constants of their hafnium complexes were determined. Hafnium was found to be extracted as the HfA4 species. The extraction parameters of the derivatives in question do not differ substantially from those of the parent substance.

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Influence of intracrystalline ionic strength in MFI zeolites on aqueous phase dehydration of methylcyclohexanols

Angewandte Chemie ◽

10.1002/ange.202107947 ◽

2021 ◽

Author(s):

Lara Milaković ◽

Peter Hintermeier ◽

Yue Liu ◽

Eszter Barath ◽

Johannes Lercher

Keyword(s):

Ionic Strength ◽

Aqueous Phase ◽

Mfi Zeolites

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Kaolin based protective barrier in municipal landfills against adverse chemo-mechanical loadings

Scientific Reports ◽

10.1038/s41598-021-89787-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Partha Das ◽

Tadikonda Venkata Bharat

Keyword(s):

Ionic Strength ◽

High Ionic Strength ◽

The Self ◽

Design Parameters ◽

Layered System ◽

Geosynthetic Clay Liners ◽

Clay Liners ◽

Landfill Liner ◽

First Time ◽

Applied Stresses

AbstractIn this work, we assess the self-sealing and swelling ability of the compacted granular bentonite (GB) under an inorganic salt environment and induced overburden stresses from the landfill waste. The laboratory permeation tests with high ionic strength salt solutions reveal that the GB fails to seal and exhibits a significant mechanical collapse under different applied stresses. The applicability of GB in the form of geosynthetic clay liners as the bottom liner facilities in landfills that produce high ionic strength salt leachates, therefore, remains a serious concern. We propose an additional barrier system based on kaolin, for the first time, to address this problem. The proposed kaolin-GB layered system performs satisfactorily in terms of its sealing and swelling ability even in adverse saline conditions and low overburden stresses. The kaolin improves the osmotic efficiency of the self and also helps the underlying GB layer to seal the inter-granular voids. The estimated design parameters by through-diffusion test suggest that the kaolin-GB layered system effectively attenuates the permeant flux and suitable as a landfill liner.

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