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Updated: Jan 16, 2026
10:08
Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
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pH-Responsive Morphological Transitions of Azobenzene-Phospholipid Vesicles
Sunnam Kim1, Shintaro Sato1, Naoki Hasegawa1
1Division of Materials Science and Chemistry, Faculty of Advanced Science and Technology, Kumamoto University, Kumamoto 860-8555, Japan.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 1, 2025
Summary
pH-responsive vesicles transform from spheres to planar bilayers in acidic conditions. This shape change, driven by piperazine linker protonation, shows potential for smart cancer drug delivery systems.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Chemical Engineering
Background:
- pH-responsive vesicles show promise for passive cancer targeting.
- Azobenzene-containing phospholipids are key components for vesicle construction.
Purpose of the Study:
- To engineer pH-responsive vesicles with tunable morphologies.
- To investigate the self-assembly and pH-induced shape transition of novel azobenzene phospholipids.
Main Methods:
- Synthesized two push-pull azobenzene phospholipids with a pH-sensitive piperazine linker.
- Utilized π-π stacking for self-assembly into spherical bilayer vesicles.
- Induce morphological transitions by altering pH to investigate vesicle response.
Main Results:
- Vesicle morphology is dictated by the orientational order of azobenzene moieties.
- Mildly acidic conditions (pH ~6) trigger vesicle transformation to planar bilayers.
- Piperazine protonation alters membrane composition and enhances orientational order.
Conclusions:
- The developed vesicles exhibit distinct shape changes in response to pH variations.
- These smart vesicles hold significant potential for targeted drug delivery applications in cancer therapy.
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