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Updated: Jul 12, 2026
08:44
Assembly and Characterization of Polyelectrolyte Complex Micelles
Published on: March 2, 2020
Complexation of polycations to anionic liposomes: composition and structure of the interfacial complexes
A V Sybachin1, A A Efimova, E A Litmanovich
1Department of Chemistry, M. V. Lomonosov Moscow State University, Leninskie Gory, Moscow 119992, Russia.
Langmuir : the ACS Journal of Surfaces and Colloids
|August 28, 2007
Summary
Poly(N-ethyl-4-vinylpyridinium bromide) adsorption onto anionic liposomes causes charge reversal and disassembly. Polymer film thickness increases with anionic lipid content, forming a barrier that limits further adsorption.
Area of Science:
- Colloid and Surface Science
- Materials Science
- Biophysics
Background:
- Liposomes are versatile drug delivery vehicles.
- Controlling liposome surface properties is crucial for their application.
- Polycation adsorption can alter liposome behavior.
Purpose of the Study:
- To investigate the adsorption of poly(N-ethyl-4-vinylpyridinium bromide) onto anionic liposomes.
- To characterize the resulting changes in liposome aggregation, charge, and structure.
- To determine the factors influencing polymer adsorption and film formation.
Main Methods:
- Electrophoretic mobility measurements to assess surface charge.
- Dynamic light scattering (DLS) to determine liposome size and polymer film thickness.
- Varying cardiolipin content in liposomes to study its effect on adsorption.
Main Results:
- Adsorption led to charge neutralization, followed by charge reversal to positive.
- Liposomes aggregated at charge neutralization but disassembled upon charge reversal.
- Polymer film thickness increased with cardiolipin content (22-35 nm).
- Adsorption reached a limit, indicating a surface saturation point.
Conclusions:
- Polymer adsorption modifies liposome surface charge and stability.
- Anionic lipid content dictates polymer film thickness and adsorption capacity.
- The adsorbed polymer forms a surface layer, not embedded in the bilayer.
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