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arXiv · 1311.5384

Global analysis of the ground-state wrapping conformation of a charged polymer on an oppositely charged nano-sphere

Hoda Boroudjerdi·Ali Naji·Roland R. Netz
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Abstract

We investigate the wrapping conformations of a strongly adsorbed polymer chain on an oppositely charged nano-sphere by employing a reduced (dimensionless) representation of a primitive chain-sphere model. This enables us to determine the global phase behavior of the chain conformation in a wide range of values for the system parameters including the chain contour length, its linear charge density and persistence length as well as the nano-sphere charge and radius, and also the salt concentration in the bathing solution. The phase behavior of a charged chain-sphere complex can be described in terms of a few distinct conformational symmetry classes (phases) separated by continuous or discontinuous transition lines which are determined by means of appropriately defined (order) parameters. Our results can be applied to a wide class of strongly coupled polymer-sphere complexes including, for instances, complexes that comprise a mechanically flexible or semiflexible polymer chain or an extremely short or long chain and, as a special case, include the previously studied example of DNA-histone complexes.

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Hoda Boroudjerdi, Ali Naji, Roland R. Netz. 2013-11-21. Global analysis of the ground-state wrapping conformation of a charged polymer on an oppositely charged nano-sphere. https://arxiv.org/abs/1311.5384

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