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DNA Nanotubes as a Versatile Tool to Study Semiflexible Polymers
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DNA as a Model for Probing Polymer Entanglements: Circular Polymers and Non-Classical Dynamics
Kathryn Regan1, Shea Ricketts2, Rae M Robertson-Anderson3
1Department of Physics and Biophysics, University of San Diego, San Diego, CA 92110, USA. keregan@sandiego.edu.
Polymers
|April 13, 2019
Summary
Double-stranded DNA (dsDNA) is a powerful tool for studying entangled polymer dynamics. Experiments reveal complex entanglement behaviors, challenging classical theories and driving new research.
Area of Science:
- Polymer Physics
- Biophysics
- Materials Science
Background:
- Entangled polymer solutions are complex systems whose dynamics are not fully understood.
- Double-stranded DNA (dsDNA) offers unique advantages for studying these dynamics due to its properties.
Purpose of the Study:
- To investigate fundamental questions about the dynamics of entangled polymer solutions using dsDNA.
- To test molecular-level entanglement theories and scaling laws.
- To explore entanglement properties of various polymer topologies.
Main Methods:
- Utilizing dsDNA's monodispersity, tunable lengths, and concentrations.
- Employing fluorescence microscopy, particle tracking, and optical tweezers for single-molecule studies.
- Applying microfluidics, microrheology, and bulk rheology for viscoelastic characterization.
Main Results:
- Elucidated debated entanglement properties of circular polymers and polymer blends.
- Revealed lengthscale and timescale dependent entanglement dynamics beyond classical tube models.
- Validated and refuted extensions and alternatives to tube theory.
Conclusions:
- dsDNA is an effective model system for probing polymer entanglement.
- Experimental findings necessitate revisions and advancements in polymer entanglement theories.
- Further theoretical work is motivated to describe complex polymer dynamics.
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