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arXiv · 1504.02884

Electrophoretic Mobility of Polyelectrolytes within a Confining Well

Tyler N. Shendruk·Martin Bertrand·Gary W. Slater
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Abstract

We present a numerical study of polyelectrolytes electrophoresing in free solution while squeezed by an axisymmetric confinement force transverse to their net displacement. Hybrid multi-particle collision dynamics and molecular dynamics simulations with mean-field finite Debye layers show that even though the polyelectrolyte chains remain "free-draining", their electrophoretic mobility increases with confinement in nanoconfining potential wells. The primary mechanism leading to the increase in mobility above the free-solution value, despite long-range hydrodynamic screening by counterion layers, is the orientation of polymer segments within Debye layers. The observed length-dependence of the electrophoretic mobility arises due to secondary effects of counterion condensation related to confinement compactification.

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Tyler N. Shendruk, Martin Bertrand, Gary W. Slater. 2015-04-11. Electrophoretic Mobility of Polyelectrolytes within a Confining Well. https://doi.org/10.1021/acsmacrolett.5b00076

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