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Updated: May 14, 2026
06:55
Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Sedimentation of knotted polymers.
J Piili1, D Marenduzzo, K Kaski
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
|February 16, 2013
Summary
Knotted polymers sediment faster with increased complexity. Sedimentation speed linearly correlates with knot crossing number and inversely with polymer size, confirming theoretical predictions.
Area of Science:
- Polymer Physics
- Computational Biophysics
- Soft Matter Physics
Background:
- Understanding polymer dynamics is crucial in biophysics.
- Knotting significantly influences polymer behavior.
- Previous studies suggested a link between knot complexity and sedimentation.
Purpose of the Study:
- To computationally investigate polymer sedimentation.
- To confirm the relationship between knot complexity and sedimentation coefficient.
- To explore the role of polymer size in sedimentation.
Main Methods:
- Utilizing stochastic rotation dynamics, a molecular dynamics algorithm.
- Simulating the sedimentation of knotted polymers.
- Analyzing the relationship between sedimentation coefficient, crossing number, and radius of gyration.
Main Results:
- Sedimentation coefficient (s) increases linearly with average crossing number (n(c)).
- Sedimentation coefficient (s) shows linear dependence on the inverse of the radius of gyration (R(g)(-1)).
- The inverse radius of gyration (R(g)(-1)) accurately measures knot complexity.
Conclusions:
- Direct computational confirmation of the linear relationship between knot complexity and sedimentation.
- The inverse radius of gyration is a reliable indicator of knot complexity.
- Hydrodynamic effects are critical in polymer sedimentation studies.
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