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Published on: February 4, 2011
Electrostatic repulsion of positively charged vesicles and negatively charged objects
1Department of Chemical Engineering, University of Delaware, Newark, DE 19716, USA. Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104 USA. Groupe de Dynamique des Phases Condensees, Case 26, Universite de Mo.
Abstract:
A positively charged, mixed bilayer vesicle in the presence of negatively charged surfaces (for example, colloidal particles) can spontaneously partition into an adhesion zone of definite area and another zone that repels additional negative objects. Although the membrane itself has nonnegative charge in the repulsive zone, negative counterions on the interior of the vesicle spontaneously aggregate there and present a net negative charge to the exterior. Beyond the fundamental result that oppositely charged objects can repel, this mechanism helps to explain recent experiments on surfactant vesicles.
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