Interaction of cationic drugs with liposomes

Interactions between cationic drugs and anionic liposomes were studied by measuring binding of drugs and the effect of binding on liposome permeability. The measurements were analyzed in the context of a continuum model based on electrostatic interactions and a Langmuir isotherm. Experiments and mod...

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Détails bibliographiques
Publié dans:Langmuir : the ACS journal of surfaces and colloids. - 1985. - 25(2009), 20 vom: 20. Okt., Seite 12056-65
Auteur principal: Howell, Brett A (Auteur)
Autres auteurs: Chauhan, Anuj
Format: Article en ligne
Langue:English
Publié: 2009
Accès à la collection:Langmuir : the ACS journal of surfaces and colloids
Sujets:Journal Article Acrylic Resins Antidepressive Agents Cations Lipid Bilayers Liposomes Pharmaceutical Preparations Phosphatidylglycerols Polymethacrylic Acids Salts plus... Unilamellar Liposomes polymethacrylic acid 25087-26-7 carbopol 940 4Q93RCW27E dimyristoylphosphatidylglycerol BI71WT9P3R Bupivacaine Y8335394RO
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Résumé:Interactions between cationic drugs and anionic liposomes were studied by measuring binding of drugs and the effect of binding on liposome permeability. The measurements were analyzed in the context of a continuum model based on electrostatic interactions and a Langmuir isotherm. Experiments and modeling indicate that, although electrostatic interactions are important, the fraction of drug sequestered in the double-layer is negligible. The majority of drug enters the bilayer with the charged regions interacting with the charged lipid head groups and the lipophilic regions associated with the bilayer. The partitioning of the drug can be described by a Langmuir isotherm with the electrostatic interactions increasing the sublayer concentration of the drug. The binding isotherms are similar for all tricyclic antidepressants (TCA). Bupivacaine (BUP) binds significantly less compared to TCA because its structure is such that the charged region has minimal interactions with the lipid heads once the BUP molecule partitions inside the bilayer. Conversely, the TCAs are linear with distinct hydrophilic and lipophilic regions, allowing the lipophilic regions to lie inside the bilayer and the hydrophilic regions to protrude out. This conformation maximizes the permeability of the bilayer, leading to an increased release of a hydrophilic fluorescent dye from liposomes
Description:Date Completed 25.01.2010
Date Revised 25.11.2016
published: Print
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/la901644h