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Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
Size and charge modulation of surfactant-based vesicles
Aurelio Barbetta1, Carlotta Pucci, Franco Tardani
1Department of Chemistry, La Sapienza University, Rome, Italy.
The Journal of Physical Chemistry. B
|September 17, 2011
Summary
Oppositely charged surfactants form vesicles, tunable in size and charge density by mole ratio and electrolytes. Unilamellar vesicles form in sodium dodecylsulfate/hexadecyltrimethylammonium bromide mixtures, crucial for biomedical applications.
Area of Science:
- Colloid and Surface Science
- Supramolecular Chemistry
- Materials Science
Background:
- Oppositely charged surfactants self-assemble into various structures.
- Vesicles are promising carriers for biomedical applications.
- Controlling vesicle properties is key for their utility.
Purpose of the Study:
- To investigate vesicle formation from nonstoichiometric mixtures of oppositely charged surfactants.
- To determine how vesicle properties (size, charge) are modulated.
- To compare vesicle formation in different surfactant systems.
Main Methods:
- Dynamic Light Scattering (DLS) for vesicle size analysis.
- Viscosity and electrophoretic mobility measurements.
- Phase diagram analysis and thermodynamic considerations.
Main Results:
- Vesicle formation observed in dilute regimes for specific surfactant mixtures.
- Vesicle size and charge density tunable via mole ratio and neutral electrolytes.
- Sodium dodecylsulfate/hexadecyltrimethylammonium bromide mixtures exhibited ideality and formed unilamellar vesicles.
- Other mixtures showed non-ideality and phase separation.
Conclusions:
- Unilamellar vesicles can be formed from specific oppositely charged surfactant mixtures.
- Vesicle properties are controllable through composition and environmental factors.
- A balance of surface tension, elasticity, and osmotic pressure ensures vesicle stability.
- Findings support the use of these vesicles as drug delivery carriers.
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