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Updated: Aug 30, 2025
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Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
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Non-equilibrium shapes and dynamics of active vesicles
Priyanka Iyer1, Gerhard Gompper1, Dmitry A Fedosov1
1Theoretical Physics of Living Matter, Institute of Biological Information Processing and Institute for Advanced Simulation, Forschungszentrum Jülich, 52425 Jülich, Germany. p.iyer@fz-juelich.de.
Soft Matter
|August 31, 2022
Summary
Active vesicles, confined self-propelled particles (SPPs) within lipid shells, exhibit diverse non-equilibrium shapes. Simulations reveal feedback between SPP activity, membrane curvature, and shape changes, enabling control for micro-robot applications.
Area of Science:
- Soft matter physics
- Biophysics
- Computational modeling
Background:
- Active vesicles, formed by self-propelled particles (SPPs) within lipid membranes, display complex non-equilibrium shapes.
- Understanding the interplay between particle activity and membrane dynamics is crucial for predicting vesicle behavior.
Purpose of the Study:
- To investigate the relationship between SPP activity, volume fraction, and active vesicle morphology.
- To analyze membrane deformations, SPP clustering, and the emergence of active tension.
Main Methods:
- Simulations of membranes modeled as dynamically triangulated surfaces enclosing active Brownian particles.
- Systematic analysis of membrane curvature, SPP clustering, and mobility.
- Development of a numerical method for tether detection.
Main Results:
- A feedback mechanism exists between membrane curvature, SPP clustering, and vesicle shape.
- Active tension in vesicles can be described by the Young-Laplace equation.
- Correlations between tether formation, length, and local curvature were identified.
Conclusions:
- SPP activity drives complex shape transformations in vesicles.
- The findings provide insights for designing steerable active vesicles and soft micro-robots.
- This research paves the way for controlled applications of active soft matter.
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