ISSN:
1432-1424
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Summary The physical state of a collagen membrane is determined, among other factors, by the concentration of electrolytes in the bathing solutions, going from a crystalline to an amorphous phase as the concentration increases. Thus, the permeation of uncharged solutes and water is strongly dependent upon the salts in the bathing solutions, which through the induced phase transition control not only the thickness and the solvent content of the membrane but also affect the magnitudes of the frictional coefficients of transport. These changes in physical parameters are reflected in variations of several hundred per cent in the values of the phenomenological coefficients ω s ,L p and σ. Experiments were performed to determine the physical state and the permeability properties of the membrane as functions of the controlling electrolyte, in this instance CaCl2, in the bathing solutions. In particular the filtration coefficientL p , the permeability coefficient for sucrose ω s , and the reflection coefficient for sucrose σ were determined via flow measurements at different salt concentrations. Complementary measurements of swelling and length variations were made. Data were reduced to membrane thickness, solvent volume-fraction, and the phenomenological coefficients. These in turn were reduced to the frictionsf sm,f sw andf wm ; there was a direct correlation between the behavior of these frictions and the physical state of the collagen membrane as indicated by the length and volume variations.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01868233
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