Abstract:
:We investigate the conditions under which nonideality in solution influences the Donnan equilibrium. Of the various parameters that characterize this equilibrium, the osmotic pressure established across the Donnan membrane is found to be particularly sensitive to intermolecular interactions between the diffusible and nondiffusible ionic species. Under physiologically appropriate conditions, we find that it is almost never valid to use Debye-Hückel theory to calculate ionic activities: it is important to take proper account of ion size. When the diffusible species is a 1-1 electrolyte, this can be done using the mean spherical approximation (MSA) for a mixture of ions of different diameters. For 2-2, or higher-valent, electrolytes one should also include the effects of the second ionic virial coefficient, which the MSA omits.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Stell G,Joslin CGdoi
10.1016/S0006-3495(86)83526-3subject
Has Abstractpub_date
1986-11-01 00:00:00pages
855-9issue
5eissn
0006-3495issn
1542-0086pii
S0006-3495(86)83526-3journal_volume
50pub_type
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