Related Experiment Video
Updated: Sep 14, 2025
11:51
Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
8.8K
Phase field model for viscous inclusions in anisotropic networks
Aakanksha Gubbala1, Anika M Jena2, Daniel P Arnold2
1Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA. stakatori@stanford.edu.
Soft Matter
|July 22, 2025
Summary
This study models lipid domain growth in actin networks, revealing that actin elasticity slows domain coarsening. Lipid domain growth is reduced compared to systems without actin networks.
Area of Science:
- Biophysics
- Soft Matter Physics
- Materials Science
Background:
- Viscous lipid domains exhibit unusual ripening when interacting with viscoelastic actin networks.
- Actin network geometry and anisotropy influence lipid domain coarsening dynamics.
Purpose of the Study:
- To develop a theoretical model explaining lipid domain ripening in lipid membrane-actin composites.
- To investigate the interplay between thermodynamic coarsening forces and actin network elasticity.
Main Methods:
- Combined Cahn-Hilliard and Landau-de Gennes liquid crystal theory.
- Incorporated actin filament characteristics using a nematic order parameter.
- Numerical simulations to analyze domain growth kinetics.
Main Results:
- Model qualitatively reproduces experimental observations of competing forces.
- Observed reduced domain growth rates: R(t) ~ t^α with α < 1/4.
- Elastic forces from the actin network resist lipid domain coarsening.
Conclusions:
- Actin network elasticity significantly alters lipid domain ripening kinetics.
- The theoretical model provides a framework for understanding elastic ripening in complex systems.
- Findings contrast with standard diffusive growth (α ~ 1/3).
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