Counterflow isotachphoresis on cellulose acetate membranes role of electroendosmosis

The diffusion of two series of alcohols and amides through complex cellulose acetate membranes was studied. The thin dense part of these membranes behaves as a nonporous layer of low water content. In this layer, called the skin, the solute diffusion coefficients, ω, depend upon size, steric configuration, and the partition coefficient, K8, between membrane and bathing solution. From the experimental values of ω and K8, the over-all friction, f, experienced by the solutes in the membrane was computed. It was found that f depends upon the chemical nature of the solute and is related to hydrogen-bonding ability. In the coarse, porous layer of the cellulose acetate membrane, diffusion occurs mainly through aqueous channels. In this instance also the hydrogen-bonding ability of the solute seems to exercise a smaller but significant influence.

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Effect of the structure of cellulose acetate membranes on their permeability, electrical conductivity and rejection

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19902933 ◽

1990 ◽

Vol 55 (12) ◽

pp. 2933-2939 ◽

Cited By ~ 1

Author(s):

Hans-Hartmut Schwarz ◽

Vlastimil Kůdela ◽

Klaus Richau

Keyword(s):

Electrical Conductivity ◽

Electrical Properties ◽

Cellulose Acetate ◽

Reverse Osmosis ◽

Water Flux ◽

Cellulose Acetate Membrane ◽

Structure Parameters ◽

Dc Electrical Conductivity ◽

Cellulose Acetate Membranes

Ultrafiltration cellulose acetate membrane can be transformed by annealing into reverse osmosis membranes (RO type). Annealing brings about changes in structural properties of the membranes, accompanied by changes in their permeability behaviour and electrical properties. Correlations between structure parameters and electrochemical properties are shown for the temperature range 20-90 °C. Relations have been derived which explain the role played by the dc electrical conductivity in the characterization of rejection ability of the membranes in the reverse osmosis, i.e. rRO = (1 + exp (A-B))-1, where exp A and exp B are statistically significant correlation functions of electrical conductivity and salt permeation, or of electrical conductivity and water flux through the membrane, respectively.

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Transport properties of Toray's asymmetric cellulose acetate membranes

Desalination ◽

10.1016/0011-9164(85)85029-3 ◽

1985 ◽

Vol 56 ◽

pp. 251-260 ◽

Cited By ~ 3

Author(s):

M. Kurihara ◽

W. Pusch ◽

T. Tanaka

Keyword(s):

Transport Properties ◽

Cellulose Acetate ◽

Cellulose Acetate Membranes

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Quantitative alkaline phosphatase isoenzyme determination by electrophoresis on cellulose acetate membranes.

Clinical Chemistry ◽

10.1093/clinchem/23.1.28 ◽

1977 ◽

Vol 23 (1) ◽

pp. 28-34 ◽

Cited By ~ 19

Author(s):

W H Siede ◽

U B Seiffert

Keyword(s):

Alkaline Phosphatase ◽

Cellulose Acetate ◽

Clinical Laboratory ◽

Kinetic Assay ◽

Specific Staining ◽

Cellulose Acetate Membranes ◽

Alkaline Phosphatase Isoenzymes ◽

Elution Method ◽

Routine Clinical Laboratory ◽

Alkaline Phosphatase Isoenzyme

Abstract We present a new method for quantitative determination of alkaline phosphatase isoenzymes. This method consists of electrophoretic separation on cellulose acetate membranes, special fixation technique to avoid elution and diffusion of enzyme protein during incubation, specific staining, and quantitative evaluation by densitometric measurement. We highly recommend the precedure for routine clinical laboratory use. In all normal individuals we observe two isoenzymes of hepatic origin and one isoenzyme each of osseous, intestinal, and biliary origin. Quantitative normal values are presented. Precision of the method is calculated, the CV being less than 10%. The exactness of densitometric quantification is proved by comparison with kinetic assay of alkaline phosphatase isoenzymes by use of an elution method. Clinical implications of alkaline phosphatase isoenzymograms are reported and discussed in detail.

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