Translocation of Star Polyelectrolytes through a Nanopore
Karthik Nagarajan1, Shing Bor Chen1
1Department of Chemical & Biomolecular Engineering , National University of Singapore , 117585 , Singapore.
The Journal of Physical Chemistry. B
|March 20, 2019
Summary
Electric field driven translocation of charged star polymers through nanopores is feasible. Critical field strength and translocation time depend on polymer architecture, enabling potential separation of different star polyelectrolytes.
Area of Science:
- Polymer Physics
- Nanotechnology
- Computational Chemistry
Background:
- Charged polymers are crucial in nanotechnology and biological systems.
- Understanding polymer behavior in confined geometries like nanopores is essential for developing advanced materials and separation techniques.
- Electric field driven translocation offers a potential method for manipulating and separating polymers at the nanoscale.
Purpose of the Study:
- To investigate the electric field driven translocation of charged star polymers through a cylindrical nanopore.
- To determine the influence of star polymer architecture (number of arms, beads per arm) on translocation dynamics.
- To explore the feasibility of using this method for separating star polyelectrolytes.
Main Methods:
- Dissipative particle dynamics (DPD) simulations were employed to model the translocation process.
- Systematic variation of star polymer parameters (number of arms, beads per arm) was performed.
- Analysis of critical field strength, translocation time, and polymer conformation within the nanopore.
Main Results:
- The critical electric field strength for translocation is dependent on the number of arms and beads per arm.
- Average translocation time shows a nonmonotonic relationship with the number of arms under good solvent conditions.
- Star polymers with more arms experience less stretching along the pore axis compared to linear polymers.
- Tension in star polymers localizes near the branch point, influencing translocation dynamics differently than linear chains.
Conclusions:
- Electric field driven translocation is a viable method for moving charged star polymers through nanopores.
- The distinct dependence of translocation dynamics on star polymer architecture suggests potential for size-based or structural separation of polyelectrolytes.
- The unique tension distribution in star polymers presents specific challenges and characteristics during nanopore passage.
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