Flunitrazepam-membrane non-specific binding and unbinding: Two pathways with different energy barriers

The effect of molecular packing on flunitrazepam's ability to interact with bio-membranes was studied using dipalmitoylphosphatidylcholine monomolecular layers at the air-water interface as a model membrane. Flunitrazepam penetrated from the subphase into monolayers at lateral pressures below 4...

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Detalles Bibliográficos
Autores: Garcia, Daniel Asmed, Perillo, Maria Angelica
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2002
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/64523
Acceso en línea:http://hdl.handle.net/11336/64523
Access Level:acceso abierto
Palabra clave:Benzodiazepine
Membrane Packing
Phosphatidylcholine Monolayer
Release And Penetration of Flunitrazepam
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:The effect of molecular packing on flunitrazepam's ability to interact with bio-membranes was studied using dipalmitoylphosphatidylcholine monomolecular layers at the air-water interface as a model membrane. Flunitrazepam penetrated from the subphase into monolayers at lateral pressures below 44.8 mN/m and induced their concentration-dependent expansion. As inferred from the values of compressibility modulus, the elasticity of the liquid-condensed phase decreased in the presence of flunitrazepam. Although this drug hardly penetrated into high-packed monolayers, it was easily incorporated in the low-packed ones at an extent sufficient to reach the partition equilibrium. Below a molecular area of 75 Å2, contrary to what would be expected, the drug surface concentration increased as a function of surface pressure, suggesting that after its penetration in disordered phases, it became energetically or physically trapped in newly-formed liquid condensed clusters. The phenomenon of flunitrazepam penetration and release would have different energy barriers depending on the membrane phase-state. Copyright © 2002 Elsevier Science B.V.