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Pearling instabilities of membrane tubes with anchored polymers
1Department of Physics of Complex Systems, The Weizmann Institute of Science, Rehovot, Israel.
Physical Review Letters
|February 15, 2001
Summary
Hydrophilic polymers with hydrophobic side groups induce pearling instability in lipid vesicles. Polymer concentration correlates with membrane curvature, revealing distinct relaxation mechanisms and predicting segregation.
Area of Science:
- Biophysics
- Polymer Science
- Materials Science
Background:
- Lipid vesicles are fundamental models for biological membranes.
- Pearling instability is a phenomenon observed in tubular structures.
- Polymers can influence membrane morphology and dynamics.
Purpose of the Study:
- To investigate the pearling instability in hollow tubular lipid vesicles induced by specific polymers.
- To understand the relationship between polymer concentration and membrane curvature.
- To elucidate the physical mechanisms governing the relaxation of pearled tubes.
Main Methods:
- Experimental study of pearling instability in lipid vesicles.
- Utilizing hydrophilic polymers with hydrophobic side groups.
- Analysis of membrane curvature and polymer concentration dynamics.
Main Results:
- Polymer concentration is directly coupled to local membrane curvature.
- The relaxation of pearled tubes exhibits two distinct time scales.
- Two underlying physical mechanisms govern the relaxation process.
Conclusions:
- The study reveals a strong correlation between polymer distribution and membrane curvature.
- A model is presented that explains the observed pearling instability and relaxation dynamics.
- The model predicts polymer segregation based on local membrane curvature at later stages.
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