Haines-Prigogle Extended Model

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The extended model of Traüble –Haines-Liebowitz. Cholesterol inhibits the water permeability of phospholipid membranes reducing it in nearly one order of magnitude at 1:4 cholesterol:phospholipid ratio. This is concomitant with a reduction in the lateral mobility of the lipids. According to the Haines-Liebowitz-Traüble model, permeability is connected to lateral diffusion [48]. In FTIR spectroscopy, there is a reduction of the  value indicating that the connected populations of CH2 increases with the cholesterol ratio, which is totally compatible with the water permeability decrease via the reduction of kinks [44]. Contribution of the interphase. Traüble´s proposal was developed further to understand the mechanism of water permeation in…show more content…
The approach is based on the definition introduced by Defay-Prigogine [52, 53] in which the surface pressure of a lipid monolayer can be described in function of the water activity at the interphase solution by equation [1] [1] This equation clearly denotes that the surface pressure () increases when decreases from below 1 and becomes zero when , i.e. the activity of pure water when lipids coverage is zero [54]. Thus, when water activity varies the surface pressure is varied. Thus surface pressure (surface tension) is a consequence of the changes in the properties of the solution at the interphase. Several reasons can concur to affect interphase water activity. One of them is relevant to this analysis considering Traüble´s model. A permeant solute may interact at the interphase by dissolution in the interphase, which decreases the water activity. In consequence, the difference of water chemical potential between aqueous solution and the membrane interphase drags water increasing the surface pressure, as an osmotic process (Figure

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