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Electromechanical Limits of Polymersomes

H. Aranda-Espinoza·H. Bermudez·F. S. Bates·D. Discher
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Abstract

Self-assembled membranes of amphiphilic diblock copolymers enable comparisons of cohesiveness with lipid membranes over the range of hydrophobic thicknesses d=3-15 nm. At zero mechanical tension the breakdown potential V_c for polymersomes with d=15 nm is 9 V compared to 1 V for liposomes with d=3 nm. Nonetheless, electromechanical stresses at breakdown universally exhibit a square dependence on V_c, and membrane capacitance shows the expected strong d-dependence, conforming to simple thermodynamic models. The viscous nature of the diblock membranes is apparent in the protracted post-poration dynamics.

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H. Aranda-Espinoza, H. Bermudez, F. S. Bates, D. Discher. 2001-07-02. Electromechanical Limits of Polymersomes. https://doi.org/10.1103/physrevlett.87.208301

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