European Biophysics Journal

, Volume 33, Issue 8, pp 706–714

Permeability and the hidden area of lipid bilayers


DOI: 10.1007/s00249-004-0415-2

Cite this article as:
Vitkova, V., Genova, J. & Bivas, I. Eur Biophys J (2004) 33: 706. doi:10.1007/s00249-004-0415-2


The passive water permeability of a lipid vesicle membrane was studied, related to the hydrostatic (not osmotic) pressure difference between the inner and the outer side of the vesicle in a water environment without additives. Each pressure difference was created by sucking a vesicle into a micropipette at a given sucking pressure. The part of the membrane sucked into the micropipette (the projection length) was measured as a function of time. The time dependence can be divided into two intervals. We put forward the idea that smoothing of membrane defects, accompanied by an increase of the membrane area, takes place during the initial time interval, which results in a faster increase of the projection length. In the second time interval the volume of the vesicle decreases due to the permeability of its membrane and the increase of the projection length is slower. The hidden area and the water permeability of a typical lipid bilayer were estimated. The measured permeability, conjugated to the hydrostatic pressure difference, is an order of magnitude higher than the known value of the permeability, conjugated to the osmotic pressure difference. A hypothesis, based on pore formation, is proposed as an explanation of this experimental result.


Membranes Permeability Surface energy Surface tension Vesicles 

Copyright information

© EBSA 2004

Authors and Affiliations

  1. 1.Laboratory of Liquid Crystals, Institute of Solid State PhysicsBulgarian Academy of SciencesSofia Bulgaria

Personalised recommendations