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Updated: Mar 27, 2026
10:08
Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
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Coupling between pore formation and phase separation in charged lipid membranes.
Hiroki Himeno1,2, Hiroaki Ito3, Yuji Higuchi4
1School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292, Japan.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2016
Summary
Charged lipids significantly influence giant unilamellar vesicle (GUV) membrane structure, leading to pore formation. Adding salt reduces pore formation, suggesting charge screening is key to membrane stability.
Area of Science:
- Biophysics
- Materials Science
- Cell Biology
Background:
- Giant unilamellar vesicles (GUVs) are crucial models for studying cell membrane properties.
- The role of lipid charge in membrane morphology is not fully understood.
- Understanding lipid mixtures is vital for biomimetic materials and drug delivery.
Purpose of the Study:
- To investigate how charged lipids affect the membrane morphology of GUVs.
- To explore the relationship between lipid composition, charge, and vesicle structure.
- To elucidate the mechanisms behind pore formation in charged lipid membranes.
Main Methods:
- Preparation and observation of GUVs using various lipid mixtures (DOPC, DPPC, DOPG, DPPG, Cholesterol).
- Fluorescent and confocal laser microscopy to analyze membrane morphologies.
- Coarse-grained molecular dynamics simulations to validate experimental findings.
Main Results:
- Spherical vesicles formed in neutral DOPC-DPPC and charged DOPC-DPPG mixtures.
- Pore formation was prevalent in GUVs containing DOPG and DPPC, and in DPPC-DPPG-Chol mixtures, increasing with DPPG concentration.
- Addition of salt suppressed pore formation, indicating the importance of charge screening.
Conclusions:
- Membrane charge is a critical determinant of GUV morphology, influencing pore formation.
- Phase separation and lipid charge interactions play significant roles in observed membrane structures.
- Simulations successfully reproduced experimental observations, supporting the proposed mechanisms.
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