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Dragging a polymer in a viscous fluid: steady state and transient
Takahiro Sakaue1, Takuya Saito, Hirofumi Wada
1Department of Physics, Kyushu University 33, Fukuoka 812-8581, Japan. sakaue@phys.kyushu-u.ac.jp
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
This study investigates single polymer chain dynamics under constant force, revealing how friction and extension depend on experimental conditions. Findings offer insights into macromolecule manipulation and biological polymer behavior.
Area of Science:
- Polymer physics
- Biophysics
- Statistical mechanics
Background:
- Macromolecule manipulation is a growing technology.
- Understanding far-from-equilibrium responses of biological polymers is crucial.
- Single polymer chain dynamics under external forces are not fully understood.
Purpose of the Study:
- To analyze the conformation and dynamics of a single polymer chain pulled by a constant force.
- To investigate the effects of finite extensibility, excluded volume, and hydrodynamic interactions.
- To elucidate generalized dynamical equations of state and tension propagation laws.
Main Methods:
- Analysis of the Rouse model for Gaussian chains.
- Application of scaling arguments to incorporate realistic polymer features.
- Derivation of analytical results and nontrivial predictions.
Main Results:
- Generalized dynamical equations of state for extension and friction laws in steady-state.
- Tension propagation laws in the transient process.
- Force-dependent friction constants and protocol-dependent dynamic friction evolution.
Conclusions:
- The study provides a theoretical framework for understanding single polymer chain behavior under force.
- Predictions can be experimentally verified using giant DNA and chromosome manipulation.
- Findings contribute to the field of macromolecular manipulation and biophysics.
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