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Updated: May 14, 2026
09:29
Obtention of Giant Unilamellar Hybrid Vesicles by Electroformation and Measurement of their Mechanical Properties by Micropipette Aspiration
Published on: January 19, 2020
Viscoelasticity of two-layer vesicles in solution
C-Y David Lu1, Shigeyuki Komura, Kazuhiko Seki
1Department of Chemistry, Center of Theoretical Physics, National Taiwan University, Taipei 106, Taiwan. cydlu@ntu.edu.tw
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 2, 2013
Summary
The study reveals two dynamic shape relaxation modes in two-layer vesicles: undulation and squeezing. Squeezing mode becomes significant at small gaps, influencing vesicle viscoelasticity and dynamic behavior under shear stress.
Area of Science:
- Soft Matter Physics
- Biophysics
- Materials Science
Background:
- Two-layer vesicles exhibit complex dynamic shape relaxation behaviors.
- Understanding these dynamics is crucial for applications involving vesicle suspensions.
Purpose of the Study:
- To calculate the dynamic shape relaxation of two-layer vesicles.
- To investigate the viscoelasticity of dilute two-layer-vesicle suspensions.
- To analyze the influence of the gap between bilayers on relaxation modes.
Main Methods:
- Computational analysis of dynamic shape relaxation.
- Calculation of viscoelastic properties of vesicle suspensions.
- Systematic variation of the gap between bilayers.
Main Results:
- Two relaxation modes identified: undulation and squeezing.
- Squeezing mode is prominent at small bilayer gaps.
- At large gaps, inner vesicle relaxation is faster than outer-layer relaxation.
- Shear stress excitation differs for each mode based on gap size.
- A crossover gap was determined, dependent on bilayer interactions.
Conclusions:
- The interplay between undulation and squeezing modes dictates vesicle dynamics.
- Bilayer gap size critically influences the viscoelastic response of vesicle suspensions.
- Systematic studies of gap variations can reveal amplitude switchings in vesicle dynamics.
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