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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Subdiffusive motion of a polymer composed of subdiffusive monomers
Stephanie C Weber1, Julie A Theriot, Andrew J Spakowitz
1Department of Biochemistry and Howard Hughes Medical Institute, Stanford University, Stanford, California 94305, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 28, 2010
Summary
Polymer motion in biological systems is often subdiffusive. Viscoelasticity and random waiting significantly alter polymer dynamics, unlike confinement or self-interaction, offering new ways to analyze experimental data.
Area of Science:
- Polymer Physics
- Biophysics
- Computational Biology
Background:
- Subdiffusive motion is common for polymers, especially biological macromolecules within cells.
- Understanding the physical drivers of this motion is crucial for comprehending cellular processes.
- Existing models may not fully capture the complexity of polymer dynamics in vivo.
Purpose of the Study:
- To investigate the physical principles governing subdiffusive polymer motion.
- To differentiate the effects of confinement, self-interaction, viscoelasticity, and random waiting on polymer dynamics.
- To develop analytical tools for interpreting experimental data on polymer motion.
Main Methods:
- Brownian dynamics simulations were employed to model polymer behavior.
- Analytical theory was used to complement simulation results.
- Fractional Langevin motion and continuous time random walks were utilized to model viscoelasticity and random waiting, respectively.
Main Results:
- Confinement and self-interaction did not alter the fundamental Rouse mode relaxations of polymers.
- Viscoelasticity and random waiting introduced significant, distinct deviations from standard polymer dynamics models.
- Monomer mean square displacement scaling and velocity autocorrelation functions were identified as key diagnostic tools.
Conclusions:
- Viscoelasticity and random waiting are key mechanisms causing subdiffusive polymer motion.
- The study provides methods to distinguish between different physical causes of subdiffusion in polymers.
- These findings aid in understanding macromolecular behavior in complex biological environments.
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