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Updated: Jun 19, 2026
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Generation of Cationic Nanoliposomes for the Efficient Delivery of In Vitro Transcribed Messenger RNA
Published on: February 1, 2019
Interaction of cationic drugs with liposomes
1Department of Chemical Engineering, University of Florida, Gainesville, Florida 32611, USA.
Langmuir : the ACS Journal of Surfaces and Colloids
|October 14, 2009
Summary
Cationic drugs interact with anionic liposomes, primarily entering the bilayer. This interaction influences liposome permeability, with tricyclic antidepressants (TCA) significantly increasing it due to their structure.
Area of Science:
- Drug Delivery Systems
- Physical Chemistry
- Materials Science
Background:
- Anionic liposomes are widely used drug delivery vehicles.
- Understanding drug-liposome interactions is crucial for optimizing drug efficacy and safety.
Purpose of the Study:
- To investigate the binding interactions between cationic drugs and anionic liposomes.
- To determine how these interactions affect liposome permeability and drug release.
Main Methods:
- Liposome preparation and characterization.
- Drug binding assays.
- Liposome permeability studies using a fluorescent dye.
- Analysis using a continuum model and Langmuir isotherm.
Main Results:
- Electrostatic interactions are important but drug sequestration in the double-layer is minimal.
- Cationic drugs partition into the liposome bilayer, interacting with lipid head groups and the bilayer core.
- Tricyclic antidepressants (TCA) exhibit similar binding isotherms and significantly increase liposome permeability.
- Bupivacaine (BUP) shows less binding due to its structure, resulting in lower permeability changes.
Conclusions:
- Drug partitioning into the liposome bilayer is the primary interaction mechanism.
- Drug structure dictates the extent of interaction and subsequent liposome permeability changes.
- TCA's linear structure facilitates maximal bilayer penetration and increased drug release.
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