Shear-driven release of a bud from a multicomponent vesicle.
Kurt A Smith1, William E Uspal
1Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
The Journal of Chemical Physics
|March 3, 2007
Summary
Shear flow can control the release of buds from multicomponent vesicles. Vesicle design and orientation determine whether shear separates or stretches buds, enabling controlled bud release.
Area of Science:
- Biophysics
- Soft Matter Physics
- Computational Biology
Background:
- Vesicles are crucial in biological processes.
- Phase separation in vesicle membranes can form buds.
- Understanding vesicle dynamics under external forces is important.
Purpose of the Study:
- To investigate the response of multicomponent budded vesicles to shear flow.
- To explore the mechanisms of bud deformation and release.
- To identify conditions for controlled bud release.
Main Methods:
- Dissipative particle dynamics simulations.
- Analysis of vesicle membrane behavior under shear.
- Examination of factors like bending rigidity and line tension.
Main Results:
- Shear flow induces varying effects on budded vesicles, including bud separation or stretching.
- Vesicle orientation significantly influences the response to shear.
- Interplay between membrane properties and shear dictates vesicle behavior.
Conclusions:
- Controlled bud release from vesicles is achievable through shear force manipulation.
- Specific vesicle designs and orientations can favor bud release.
- This study provides a framework for designing vesicles with shear-responsive properties.
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