Definition of Donnan equilibrium in English:

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Donnan equilibrium

Pronunciation: /ˌdänən ˌēkwəˈlibrēəm/


The equilibrium reached between two ionic solutions separated by a semipermeable membrane when one or more of the kinds of ion present cannot pass through the membrane. The result is a difference in osmotic pressure and electrical potential between the solutions.
Example sentences
  • In conclusion, we have established the role played by high-salt incubation and Donnan equilibrium in understanding the osmotic shock properties of viral capsids.
  • A time-honored way to take into account the difference between salt concentrations inside and outside the capsid during the incubation phase, due to Donnan equilibrium effects, is within the context of a cell model treatment.
  • Again, this is due to the Donnan equilibrium effect, i.e., to the difference between inside and outside salt concentrations arising from the large density of fixed charge confined in the capsid.


Early 20th century: named after Frederick G. Donnan (1870–1956), British physical chemist.

For editors and proofreaders

Syllabification: Don·nan e·qui·lib·ri·um

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