A model of anomalous chain translocation dynamics
Srabanti Chaudhury1, Binny J Cherayil
1Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore-560012, India.
The Journal of Physical Chemistry. B
|April 16, 2009
Summary
This study introduces a generalized Langevin equation model to explain polymer translocation anomalies. The model accurately predicts polymer passage times and monomer movement, improving upon simple diffusion theories.
Area of Science:
- Physics
- Physical Chemistry
- Biophysics
Background:
- Polymer translocation through pores is crucial in biological and synthetic systems.
- Anomalies in translocation times challenge simple Brownian diffusion models.
- Understanding these dynamics is key for nanotechnology and molecular biology.
Purpose of the Study:
- To develop a theoretical model for polymer translocation incorporating long-ranged temporal correlations.
- To explain discrepancies between experimental and simulated polymer passage times.
- To provide a more accurate framework for analyzing translocation dynamics.
Main Methods:
- Formulation of a one-dimensional generalized Langevin equation.
- Analysis of stochastic dynamics of monomers across a pore.
- Calculations of mean first passage time and mean square displacement under varying bias.
Main Results:
- The generalized Langevin equation model successfully rationalizes anomalies in polymer translocation.
- Calculated scaling exponents show good agreement with experimental and simulation data.
- The model accounts for deviations from simple Brownian diffusion.
Conclusions:
- The proposed model offers a robust explanation for complex polymer translocation phenomena.
- It provides a valuable tool for predicting and understanding polymer behavior in confined geometries.
- This work advances the theoretical understanding of polymer dynamics in nanopores.
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