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Published on: May 20, 2014
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Equilibrium organization, conformation, and dynamics of two polymers under box-like confinement
James M Polson1, Desiree A Rehel1
1Department of Physics, University of Prince Edward Island, 550 University Ave., Charlottetown, Prince Edward Island C1A 4P3, Canada. jpolson@upei.ca.
Soft Matter
|May 24, 2021
Summary
Two polymer chains in a confined box show unique arrangements and movement. Confinement primarily reduces polymer size, while crowding impacts dynamics, with polymers often occupying opposite sides of the cavity.
Area of Science:
- Polymer physics
- Computational biophysics
- Nanofluidics
Background:
- Understanding polymer behavior in confined spaces is crucial for nanofluidic devices.
- Recent experiments motivate detailed simulation studies of confined polymers.
Purpose of the Study:
- To investigate the conformation, organization, and dynamics of two flexible polymer chains within a box-like cavity.
- To explore the interplay between confinement and inter-polymer crowding.
Main Methods:
- Brownian dynamics simulations
- Monte Carlo simulations
- Modeling polymers as flexible bead-spring chains
- Simulating a box-like cavity with a square cross-section and small height.
Main Results:
- Polymer size reduction is mainly due to confinement, not crowding.
- Inter-polymer crowding significantly affects polymer diffusion and internal motion.
- Polymers exhibit a tendency to occupy opposite positions within the cavity.
- Center-of-mass distribution shows a depletion zone and 4-fold symmetry.
Conclusions:
- The study reveals distinct static and dynamic behaviors compared to polymers in narrow channels.
- Simulation results align with experimental observations of DNA in nanofluidic cavities.
- Confinement and crowding effects are significant in box-like cavities, influencing polymer organization and dynamics.
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