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07:31
Realistic Membrane Modeling Using Complex Lipid Mixtures in Simulation Studies
Published on: September 1, 2023
Interaction of ionic surfactants with cornea-mimicking anionic liposomes
Chhavi Gupta1, Andrew K Daechsel, Anuj Chauhan
1Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, USA.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 27, 2011
Summary
Ionic surfactants transiently increase liposome permeability, causing dye leakage. Cationic surfactants induce faster healing and greater leakage than anionic surfactants, revealing insights into ocular epithelia interactions.
Area of Science:
- Biophysics
- Materials Science
- Ocular Surface Science
Background:
- Surface-active molecules interact with lipid bilayers in biological and technological systems.
- Liposomes mimicking ocular epithelia are crucial models for studying drug delivery and ocular surface interactions.
Purpose of the Study:
- To investigate the interaction of ionic surfactants with liposomes modeling ocular epithelia.
- To quantify the effect of surfactants on liposome permeability and dye release kinetics.
Main Methods:
- Liposomes mimicking ocular epithelia were loaded with calcein dye.
- Exposure to varying concentrations and ionic strengths of cationic and anionic surfactants.
- Measurement of calcein dye leakage rates to assess bilayer permeability changes.
Main Results:
- Surfactant exposure increased liposome permeability, causing dye release, followed by a finite healing period.
- Cationic surfactants exhibited two leakage timescales, while anionic surfactants showed one.
- Dye leakage increased with surfactant concentration, being significantly higher for cationic surfactants.
- Healing timescale decreased with increasing surfactant concentration; ionic strength enhanced leakage for anionic surfactants.
Conclusions:
- Ionic surfactants transiently increase liposome permeability, with subsequent bilayer healing.
- Differences in leakage and healing kinetics between cationic and anionic surfactants suggest distinct interaction mechanisms.
- Findings provide insights into surfactant-lipid interactions relevant to ocular surface dynamics and potential therapeutic applications.
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