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Updated: Jun 29, 2026

Electrophoretic Separation of Proteins
Published on: June 12, 2008
Free solution electrophoresis of homopolyelectrolytes
Abstract:
We investigate the behavior of single polyelectrolytes in multivalent salt solutions under the action of electric fields through computer simulations. The chain is unfolded in a strong electric field and aligned parallel to the field direction, and the chain size shows a sigmoidal transition. The unfolding electric field E* depends on the salt concentration and scales as V (-1/2) with V being the ellipsoidal volume occupied by the chain. The magnitude of the electrophoretic mobility of chain drastically increases during the unfolding. The fact that E* depends on the chain length provides a plausible mechanism to separate long charged homopolymers by size in free solution electrophoresis via the unfolding transition of globule polyelectrolytes condensed by multivalent salt.
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