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Updated: May 30, 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
Vesicle deformation and poration under strong dc electric fields
Mohamed M Sadik1, Jianbo Li, Jerry W Shan
1Department of Mechanical and Aerospace Engineering, Rutgers, The State University of New Jersey, 98 Brett Road, Piscataway, New Jersey 08854, USA.
Summary
Giant lipid vesicles deform significantly under strong electric fields, with deformation scaling quadratically with field strength. This study explores a strong-deformation regime, revealing insights into membrane mechanics and electroporation.
Area of Science:
- Biophysics
- Membrane Biophysics
- Soft Matter Physics
Background:
- Lipid membranes exhibit complex responses to electric fields, including electrodeformation and electroporation.
- Giant unilamellar vesicles (GUVs) are model systems for studying cell membrane behavior.
Purpose of the Study:
- Investigate the electrodeformation of GUVs under strong DC electric fields.
- Quantify deformation as a function of electric field strength and conductivity ratio.
- Explore a strong-deformation regime of GUVs.
Main Methods:
- Experiments using L-α-phosphatidylcholine GUVs (14-30 μm diameter).
- Applied electric fields ranging from 0.9 to 2.0 kV/cm.
- Varied intra-to-extra-vesicular conductivity ratios (1.92 to 53.0).
Main Results:
- GUVs exhibited prolate elongations along the electric field direction.
- Aspect ratios exceeded 10 in a strong-deformation regime.
- Deformation scaled quadratically with field strength and asymptotically with conductivity ratio.
- Observed area and volumetric changes indicated concurrent electroporation.
Conclusions:
- A theoretical model was developed for large deformations in the strongly permeabilized limit.
- Model predictions showed both agreement and discrepancies with experimental data.
- Study highlights limitations and potential extensions for modeling strong GUV deformations and electroporation.
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