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Updated: Jul 2, 2025
08:51
Monitoring Protein Adsorption with Solid-state Nanopores
Published on: December 2, 2011
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Nonmonotonic polymer translocation kinetics through nanopores under changing surface-polymer interactions
Neha Manohar1, Robert A Riggleman1, Daeyeon Lee1
1Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
The Journal of Chemical Physics
|February 29, 2024
Summary
Polymer translocation dynamics in confined spaces are complex. Attractive surface interactions initially speed up polymer movement but can slow it down if adsorption occurs, impacting polymer upcycling and bioseparation applications.
Area of Science:
- Polymer Physics
- Soft Matter Physics
- Physical Chemistry
Background:
- Understanding polymer dynamics in confined environments is crucial for applications like polymer upcycling and bioseparations.
- Existing models often simplify the interplay of surface interactions, solvation, and confinement.
Purpose of the Study:
- To develop an entropic barrier model using self-consistent field theory to study polymer translocation kinetics.
- To investigate the influence of attractive surface interactions, excluded volume, and cavity size on polymer translocation dynamics.
Main Methods:
- Development of an entropic barrier model based on self-consistent field theory.
- Simulation of polymer translocation through a single-segment-width nanopore between two cavities.
- Analysis of the mean translocation time (τ) as a function of surface interaction strength (ɛ) and excluded volume (u0).
Main Results:
- A nonmonotonic dependence of mean translocation time on surface interaction strength was observed for polymers in a good solvent.
- At low surface attraction, excluded volume effects dominate, increasing translocation time.
- Increased surface attraction initially accelerates translocation by counteracting excluded volume, but strong attraction leads to adsorption and significantly slower kinetics.
- The adsorption transition point depends on excluded volume strength.
- Translocation kinetics are influenced by the relative sizes of the cavities, with faster translocation into smaller cavities and slower translocation into larger ones under increasing surface attraction.
Conclusions:
- Surface interactions play a complex, nonmonotonic role in polymer translocation kinetics.
- The balance between excluded volume, surface attraction, and confinement dictates translocation efficiency.
- The developed model provides insights into designing systems for controlled polymer transport in nano- and micro-devices.
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