Author/Editor     Kaes, J; Sackmann, E; Podgornik, R; Svetina, S; Žekš, B
Title     Thermally induced budding of phospholipid vesicles - a discontinuous process
Type     članek
Source     J Phys II France
Vol. and No.     Letnik 3
Publication year     1993
Volume     str. 631-45
Language     eng
Abstract     The process of thermally induced budding is studied for DMPC vesicles. With increasing temperature a pear shaped vesicle changes discontinuosly into a pair of spherical vesicles connected by a narrow neck. In the course of the colling process a thermal hysteresis in a stepwise manner is observed. The size of the daughter vesicle diminishes by repeated widening and narrowing of the neck until it finally remains open and the vesicle attains the pear shape again. These experimental findings are difficult to rationalize within the bare bilayer couple model of phospholipid vesicles. To model the discontinuous behavior in the heating process the expansion of the elastic energy of the bilayer up to the third order in the area difference of the two monolayers is empirically introduced. The van der Waals forces between mother and daughter vesicles are shown to be responsible for the repeated widening and narrowing of the neck in the cooling process.
Descriptors     PHOSPHOLIPIDS
TEMPERATURE
THERMODYNAMICS
BIOPHYSICS