What is Donnan membrane effect?
The Gibbs–Donnan effect (also known as the Donnan’s effect, Donnan law, Donnan equilibrium, or Gibbs–Donnan equilibrium) is a name for the behaviour of charged particles near a semi-permeable membrane that sometimes fail to distribute evenly across the two sides of the membrane.
What factors that can affect the Donnan equilibrium?
In considering Donnan hydrolysis, two factors are important: (a) a separate aqueous phase must exist (the outer solution), (b) hydrogen and aluminium ions must replace the calcium, leading to an acidic exchange complex.
What is the significance of Donnan membrane equilibrium?
Donnan equilibrium (which can also be referred to as the Gibbs-Donnan equilibrium) describes the equilibrium that exists between two solutions that are separated by a membrane. The membrane is constructed such that it allows the passage of certain charged components (ions) of the solutions.
What is Donnan exclusion effect?
The Donnan exclusion effect, also known as the Gibbs-Donnan effect, is used to describe the distribution of charged ions near a permeable membrane for the organism.
How is Donnan effect prevented?
Since the accumulation of ions within any cell is followed by osmosis of water molecules, cell edema due to the Donnan effect of cell proteins is prevented through the action of Na+/K+ pumps. They expel 3 Na+ and import 2 K+ in every cycle, so some water also leaves the cell.
What is Donnan’s theory What is its important in biophysical chemistry?
The theory of the Donnan membrane equilibrium has important applications in colloid chemistry and in the technologies of leather and gelatin, but above all in the understanding of the living cell, where it can give a quantitative account of ionic equilibria both within the cell and between the cell and its environment.
What is the relationship of Donnan membrane equilibrium with pH?
In equilibrium dialysis, with a nondiffusible, charged protein on one side of the membrane, Donnan equilibrium leads to a pH difference across the membrane.
What is the Donnan product rule?
At Gibbs-Donnan equilibrium, On each side of the membrane, each solution will be electrically neutral. The product of diffusible ions on one side of the membrane will be equal to the product of diffusible ions on the other side of the membrane.
What is Donnan equilibrium Slideshare?
Gibbs-Donnan membrane Equilibrium- relevance in Cell Physiology. The Gibbs-Donnan effect describes the unequal distribution of permeant charged ions on either side of a semipermeable membrane which occurs in the presence of impermeant charged ions.
What is the Donnan effect in ultrafiltration?
Such interactions can create an offset between excipient levels in final products and diafiltration buffers in ultrafiltration processes. The effect of such electrostatic interactions in a membrane process is known as the Donnan effect. The Donnan effect on excipient levels has received significant attention in recent years.
What is the Donnan effect in cell membrane separation?
The separation through NF membranes is the integrated outcome of Donnan, transport, dielectric, and steric effects. The Donnan effect refers to the equilibrium and interaction between a soluble charged molecule and charge existing on membrane (Donnan, 1995 ).
Does the Donnan effect affect excipient levels in monoclonal antibody production?
The Donnan effect on excipient levels has received significant attention in recent years. Theoretical modeling has been developed to predict excipient and pH changes as a result of the Donnan effect in monoclonal antibody (MAb) processes.
Is the Donnan effect important to account for during Preformulation studies?
It is important to account for the Donnan effect during preformulation studies. The excipients levels in an ultrafiltration pool may differ from the levels in a protein solution obtained by adding buffers into concentrated protein solutions due to the Donnan effect. Copyright © 2010 American Institute of Chemical Engineers (AIChE).