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Hard Spheres in Vesicles: Curvature-Induced Forces and Particle-Induced Curvature

A. D. Dinsmore·D. T. Wong·Philip Nelson·A. G. Yodh
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Abstract

We explore the interplay of membrane curvature and nonspecific binding due to excluded-volume effects among colloidal particles inside lipid bilayer vesicles. We trapped submicron spheres of two different sizes inside a pear-shaped, multilamellar vesicle and found the larger spheres to be pinned to the vesicle's surface and pushed in the direction of increasing curvature. A simple model predicts that hard spheres can induce shape changes in flexible vesicles. The results demonstrate an important relationship between the shape of a vesicle or pore and the arrangement of particles within it.

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A. D. Dinsmore, D. T. Wong, Philip Nelson, A. G. Yodh. 1997-10-01. Hard Spheres in Vesicles: Curvature-Induced Forces and Particle-Induced Curvature. https://doi.org/10.1103/physrevlett.80.409

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