Conformal transformations of vesicle shapes

نویسنده

  • Udo Seifert
چکیده

Vesicles are closed surfaces of lipid bilayers, which form already in simple binary systems of one lipid species plus water [IJ. Studies by video microscopy reveal an amazing variety of shapes, between which transformations can be induced, e.g., by changing the temperature or the osmotic conditions [2-4]. Such experiments confirm the basic theoretical idea that the bending elasticity of the bilayer together with constraints on area A and enclosed volume V determine the vesicle shape [5]. If the vesicle is described as a two-dimensional surface embedded in three-dimensional spa<:e, the bending elastic energy can be expressed in terms of the curvature of this surface. Two models have been investigated in some detail. (il In the spontaneous curvature model [5,6], the bending energy is given by F s; (K/2) f dA(2H CO)2 (1 )

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تاریخ انتشار 2011