Thermal fluctuations of large quasi-spherical bimolecular phospholipid vesicles

摘要: The time correlation function of the fluctuations in shape large ( ~ 10 03BCm) quasi-spherical hydrated phospholipid membrane vesicles consisting one to several bimolecular layers is measured. These membranes are flaccid, so vesicle area and volume remain constant only contribution energy fluctuating from excess curvature a element. A value for elastic modulus, Kc, obtained mean-square amplitude normal modes using equipartition theorem. An expression found by solving dynamics relaxation against low Reynolds number viscous drag water. restoring force calculated following theory Jenkins [1] which treats as two dimensional incompressible fluid. Kc d0, pressure plane. measurements yield 1-2 10-12 ergs, agreement with other experiments on artificial [2, 3], values d0 theoretical range predicted [1]. reason lower published deduced [4] red blood cell suggested.