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arXiv · 1604.04787

Switch-like surface binding of competing multivalent particles

Nicholas B. Tito·Daan Frenkel
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Abstract

Multivalent particles competing for binding on the same surface can exhibit switch-like behaviour, depending on the concentration of receptors on the surface. When the receptor concentration is low, energy dominates the free energy of binding, and particles having a small number of strongly-binding ligands preferentially bind to the surface. At higher receptor concentrations, multivalent effects become significant, and entropy dominates the binding free energy; particles having many weakly-binding ligands preferentially bind to the surface. Between these two regimes there is a "switch-point", at which the surface binds the two species of particles equally strongly. We demonstrate that a simple theory can account for this switch-like behaviour and present numerical calculations that support the theoretical predictions. We argue that binding selectivity based on receptor density, rather than identity, may have practical applications.

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Nicholas B. Tito, Daan Frenkel. 2016-04-16. Switch-like surface binding of competing multivalent particles. https://doi.org/10.1140/epjst%2Fe2016-60119-6

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