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Criteria for minimal model of driven polymer translocation
P M Suhonen1, K Kaski1, R P Linna1
1Department of Biomedical Engineering and Computational Science, Aalto University, P.O. Box 12200, FI-00076 Aalto, Finland.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 7, 2014
Summary
Finite polymer translocation is complex. Our study reveals that including fluctuations and the trans side is crucial for accurate models, contradicting simpler, incomplete models.
Area of Science:
- Polymer physics
- Statistical mechanics
- Biophysics
Background:
- Driven polymer translocation is vital for biological processes and nanotechnology.
- Understanding finite-sized polymer behavior is key for experimental and simulation studies.
- The scaling exponent (α) of translocation time remains debated for finite polymers.
Purpose of the Study:
- To investigate the influence of model completeness on driven polymer translocation dynamics.
- To clarify the behavior of the scaling exponent (α) with varying driving forces (fp).
- To identify essential components for accurate minimal models of polymer translocation.
Main Methods:
- Langevin dynamics simulations of polymer translocation.
- Comparison of complete, modified, and minimal translocation models.
- Utilizing the freely jointed-chain polymer model.
Main Results:
- Incomplete models excluding trans side and fluctuations contradict complete models.
- The scaling exponent (α) increases with driving force (fp) in complete models.
- A minimal model excluding dynamics can align with full translocation models.
Conclusions:
- Fluctuations significantly impact driven polymer translocation.
- Incomplete models yield erroneous characteristics.
- Minimal models must incorporate essential physical aspects for accuracy.
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