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arXiv · 1708.06921

Complex Fluids with Mobile Charge-Regulated Macro-Ions

Tomer Markovich·David Andelman·Rudi Podgornik
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Abstract

We generalize the concept of charge regulation of ionic solutions, and apply it to complex fluids with mobile macro-ions having internal non-electrostatic degrees of freedom. The suggested framework provides a convenient tool for investigating systems where mobile macro-ions can self-regulate their charge (e.g., proteins). We show that even within a simplified charge-regulation model, the charge dissociation equilibrium results in different and notable properties. Consequences of the charge regulation include a positional dependence of the effective charge of the macro-ions, a non-monotonic dependence of the effective Debye screening length on the concentration of the monovalent salt, a modification of the electric double-layer structure, and buffering by the macro-ions of the background electrolyte.

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cond-mat.softcond-mat.mtrl-scicond-mat.stat-mechphysics.bio-phphysics.chem-ph

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Tomer Markovich, David Andelman, Rudi Podgornik. 2017-08-23. Complex Fluids with Mobile Charge-Regulated Macro-Ions. https://doi.org/10.1209/0295-5075%2F120%2F26001

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