Institute for Medicine and Engineering Papers

Pore stability and dynamics in polymer membranes

Harry Bermudez, University of Pennsylvania
Halim Aranda-Espinoza, University of Pennsylvania
Daniel A. Hammer, University of Pennsylvania
Dennis E. Discher, University of Pennsylvania

Document Type Journal Article

Reprinted from Europhysics Letters, Volume 64, Issue 4, November 2003, pages 550-56.
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Vesicles self-assembled from amphiphilic diblock copolymers exhibit a wide diversity of behavior upon poration, due to competitions between edge, surface and bending energies, while viscous dissipation mechanisms determine the time scales. The copolymers are essentially chemically identical, only varying in chain length (related to the membrane thickness d). For small d, we find large unstable pores and the resulting membrane fragments reassemble into vesicles within minutes. For large d, however, submicron pores form and are extremely long-lived. The results show that pore behavior depends strongly on d, suggesting that the relevant energies depend on d and pore size r in a more complex manner than what is generally assumed. Further control over these systems would make them useful for numerous applications.


Date Posted: 02 August 2007

This document has been peer reviewed.