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arXiv · 0804.3329

Polymer-induced tubulation in lipid vesicles

F. Campelo·A. Hernandez-Machado
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Abstract

A mechanism of extraction of tubular membranes from a lipid vesicle is presented. A concentration gradient of anchoring amphiphilic polymers generates tubes from bud-like vesicle protrusions. We explain this mechanism in the framework of the Canham-Helfrich model. The energy profile is analytically calculated and a tube with a fixed length, corresponding to an energy minimum, is obtained in a certain regime of parameters. Further, using a phase-field model, we corroborate these results numerically. We obtain the growth of tubes when a polymer source is added, and the bud-like shape after removal of the polymer source, in accordance with recent experimental results.

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F. Campelo, A. Hernandez-Machado. 2008-04-21. Polymer-induced tubulation in lipid vesicles. https://doi.org/10.1103/physrevlett.100.158103

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