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Updated: Jun 24, 2026
10:43
Preparation, Purification, and Use of Fatty Acid-containing Liposomes
Published on: February 9, 2018
pH-responsive jello: gelatin gels containing fatty acid vesicles
Matthew B Dowling1, Jae-Ho Lee, Srinivasa R Raghavan
1Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742-2111, USA.
Langmuir : the ACS Journal of Surfaces and Colloids
|March 26, 2009
Summary
We developed pH-responsive biopolymer gels by embedding pH-sensitive sodium oleate (NaOA) vesicles. Changing the pH triggers vesicle-to-micelle transitions, enabling controlled release of encapsulated substances from the gel.
Area of Science:
- Materials Science
- Biotechnology
- Chemical Engineering
Background:
- Biopolymer gels are widely used but often lack tunable properties.
- pH-responsive materials are crucial for controlled release applications.
- Sodium oleate (NaOA) vesicles transform into micelles at specific pH changes.
Purpose of the Study:
- To create pH-responsive biopolymer gels.
- To investigate the controlled release of encapsulated substances.
- To functionalize gelatin gels with pH-sensitive vesicle systems.
Main Methods:
- Embedding sodium oleate (NaOA) vesicles into gelatin gels at pH 8.3.
- Exposing the vesicle-loaded gel to a pH 10 buffer solution.
- Observing the vesicle-to-micelle transition and solute release using turbidity and calcein dye.
Main Results:
- A pH-driven vesicle-to-micelle transition front was observed within the gel.
- Spatially selective micelle domains could be created.
- Calcein dye release experiments confirmed pH-tunable controlled release.
Conclusions:
- Embedding pH-sensitive NaOA vesicles imparts pH-responsiveness to gelatin gels.
- This approach enables tunable, pH-dependent controlled release of encapsulated hydrophilic solutes.
- The method offers a novel strategy for developing smart biomaterials.
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