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A Tripeptide-Stabilized Nanoemulsion of Oleic Acid
Published on: February 27, 2019
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Nanoemulsions Stable against Ostwald Ripening
Yanlin Guo1, Xinpeng Zhang1, Xiaohan Wang1
1Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, Shandong University, Jinan, Shandong 250100, P. R. China.
Langmuir : the ACS Journal of Surfaces and Colloids
|January 4, 2024
Summary
Stable nanoemulsions were created without Ostwald ripening, a common droplet growth issue. This research highlights the importance of micelle absence for nanoemulsion stability and potential pesticide delivery applications.
Area of Science:
- Colloid and Surface Chemistry
- Materials Science
- Physical Chemistry
Background:
- Ostwald ripening causes droplet growth in oil-in-water (O/W) nanoemulsions, particularly at high surfactant concentrations.
- This phenomenon is linked to micelle presence in the water phase and the oil's aqueous solubility.
- Spontaneously formed nanoemulsions are susceptible to Ostwald ripening under specific conditions.
Purpose of the Study:
- To investigate the stability of spontaneously formed O/W nanoemulsions against Ostwald ripening.
- To elucidate the role of micelles in the occurrence of Ostwald ripening in these systems.
- To explore the potential of stable nanoemulsions as nanocarriers for water-insoluble substances.
Main Methods:
- O/W nanoemulsions were spontaneously formed using fatty alcohol polyoxypropylene polyoxyethylene ether (APE).
- Droplet size was monitored using dynamic light scattering to assess Ostwald ripening.
- Surface and interfacial tension measurements were used to determine APE's partition coefficient and interfacial adsorption.
Main Results:
- The spontaneously formed O/W nanoemulsions exhibited stability against Ostwald ripening.
- Addition of micelles to the nanoemulsion system induced droplet growth, confirming their role in Ostwald ripening.
- The study analyzed APE's phase distribution and adsorption behavior to understand micelle formation.
Conclusions:
- Absence of micelles is crucial for preventing Ostwald ripening and achieving stable nanoemulsions.
- Spontaneously formed O/W nanoemulsions, free from Ostwald ripening, are viable nanocarriers for pesticides.
- This work offers a new method for preparing stable nanoemulsions and deepens the understanding of nanoemulsion instability mechanisms.
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