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Nonlinear Elasticity of Single Collapsed Polyelectrolytes

Hirofumi Wada·Yoshihiro Murayama·Masaki Sano
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Abstract

Nonlinear elastic responses of short and stiff polyelectrolytes are investigated by dynamic simulations on a single molecule level. When a polyelectrolyte condensate undergoes a mechanical unfolding, two types of force-extension curves, i.e., a force plateau and a stick-release pattern, are observed depending on the strength of the electrostatic interaction. We provide a physical interpretation of such force-extension behavior in terms of intramolecular structures of the condensates. We also describe a charge distribution of condensed counterions onto a highly stretched polyelectrolyte, which clarifies a formation of one-dimensional strongly correlated liquid at large Coulomb coupling regime where a stick-release pattern is observed. These findings may provide significant insights into the relationship between a molecular elasticity and a molecular mechanism of like-charge attractions observed in a wide range of charged biopolymer systems.

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Hirofumi Wada, Yoshihiro Murayama, Masaki Sano. 2004-09-28. Nonlinear Elasticity of Single Collapsed Polyelectrolytes. https://doi.org/10.1103/physreve.72.041803

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