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Proper Determination of Phase Diagrams while Nanoprecipitating Oils
Yiping Chen1, Adèle Mosa1, Sacha Bouvier1
1Univ Lyon, CNRS, UMR 5223, Ingénierie des Matériaux Polymères, Université Claude Bernard Lyon 1, INSA Lyon, Université Jean Monnet, F-69621 Villeurbanne Cedex, France.
Langmuir : the ACS Journal of Surfaces and Colloids
|June 5, 2024
Summary
Researchers developed new methods to accurately determine Ouzo limits for oil nanodroplet formation. This improves understanding and control of colloidal dispersion processes, crucial for material science applications.
Area of Science:
- Colloid and Surface Science
- Materials Chemistry
- Physical Chemistry
Background:
- The Ouzo effect describes generating colloidal dispersions from various solutes.
- Establishing phase diagrams for oil nanoprecipitation is challenging due to nanodroplet stability.
- Understanding these boundaries is key to controlling aggregation during nanoprecipitation.
Purpose of the Study:
- To propose and validate complementary methods for accurately determining Ouzo limits in ternary oil/solvent/nonsolvent systems.
- To investigate the influence of surfactants on Ouzo limits.
- To enhance the understanding and control of aggregation in oil-based colloidal dispersions.
Main Methods:
- Utilized fluorescence microscopy to determine Ouzo limits in systems without surfactants.
- Employed dynamic light scattering to determine Ouzo limits in systems with surfactants.
- Combined these techniques for accurate phase diagram determination.
Main Results:
- Successfully determined Ouzo limits in ternary oil/solvent/nonsolvent systems with fair accuracy.
- Demonstrated the utility of fluorescence microscopy and dynamic light scattering for this purpose.
- Provided a pathway for precise phase diagram determination in complex systems.
Conclusions:
- The proposed methods offer accurate determination of Ouzo limits for oil nanoprecipitation.
- This improved accuracy facilitates better understanding and control of aggregation phenomena.
- The findings pave the way for optimized design of colloidal dispersions.
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