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08:59
Lipid Exchange Assay in Living Cells
Published on: March 21, 2025
Amphiphilic behavior and membrane solubility of a dicholesteryl-cyclodextrin
Angelika Klaus1, Christophe Fajolles, Martin Bauer
1UMR 3299 Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA)/Centre National de la Recherche Scientifique (CNRS), SIS2M, Laboratoire Interdisciplinaire sur l'Organisation Nanométrique et Supramoléculaire (LIONS), CEA Saclay, 91191 Gif sur Yvette, France.
Langmuir : the ACS Journal of Surfaces and Colloids
|May 20, 2011
Summary
Amphiphilic cyclodextrins (CDs) like TBdSC can modify membranes. This study reveals how TBdSC interacts with DPPC lipid monolayers, showing solubility and phase segregation under pressure.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Biophysics
Background:
- Amphiphilic cyclodextrins (CDs) are versatile for functionalizing natural and synthetic membranes.
- Understanding their interfacial behavior is crucial for membrane modification applications.
Purpose of the Study:
- To investigate the interfacial behavior of a specific amphiphilic cyclodextrin, TBdSC.
- To elucidate the insertion and structural adaptation of TBdSC within a dipalmitoyl-l-α-phosphatidylcholine (DPPC) monolayer model.
Main Methods:
- Langmuir isotherms to study interfacial pressure-area relationships.
- X-ray reflectivity to probe structural reorganization.
- Brewster angle microscopy (BAM) and Atomic Force Microscopy (AFM) for in-plane structural characterization.
Main Results:
- Pure TBdSC exhibits conformational reorganization upon compression, adaptable to molecular area.
- TBdSC is soluble in liquid-expanded DPPC but undergoes phase segregation at higher pressures.
- Distinct phases of liquid-condensed DPPC and high-pressure TBdSC conformation emerge, causing contrast inversion in imaging.
Conclusions:
- TBdSC demonstrates tunable interfacial behavior and conformational flexibility.
- The study provides insights into TBdSC-DPPC mixtures, relevant for designing functionalized lipid systems.
- Observed phase segregation and contrast inversion highlight complex molecular interactions at interfaces.
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