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Caracterización y control de la fluidez de la capa lipídica en las membranas de doble capa híbrida
Neil A Anderson1, Lee J Richter, John C Stephenson
1Department of Physics, National Institute of Standards and Technology, 100 Bureau Drive MS8443, Gaithersburg, Maryland 20899-8443, USA.
Journal of the American Chemical Society
|February 1, 2007
Resumen
La temperatura de transición de fase de gel a cristal líquido de las membranas de doble capa híbrida puede ser controlada por la monocapa autoensamblada subyacente. Este hallazgo ofrece información sobre el ajuste de las propiedades de la membrana lipídica para aplicaciones avanzadas.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La biofísica es la biofísica.
- Química de las superficies.
Sus antecedentes:
- Las membranas de doble capa híbridas (HBM) son sistemas modelo para estudiar el comportamiento de las membranas lipídicas.
- La temperatura de transición de fase de gel a cristal líquido (LC), T (m), es una propiedad crítica de las bicapas lipídicas.
- Estudios previos mostraron que T ((m) se ve afectado por la capa subyacente monocapa autoensamblada (SAM) en los HBM.
Objetivo del estudio:
- Para investigar la influencia de la capa subyacente SAM en el T (m) de la capa lipídica distal en HBMs.
- Para establecer el control sobre la capa lipídica HBM T(m) a través de la modificación SAM.
- Para explorar la relación entre la composición / embalaje de SAM y la capa superior de lípidos T(m).
Principales métodos:
- Utilizó la espectroscopia de frecuencia de suma vibratoria (VSFS) por su sensibilidad al orden/desorden de la cadena de acilo lípido.
- Se varió sistemáticamente la composición de la capa subyacente del SAM (tiol alcano, tiolipido, SAM mixtos).
- T (m) medido para las superposiciones de lípidos de fosfatidilcolina en diferentes SAM.
Principales resultados:
- Se ha demostrado que T(m) de la capa lipídica en HBMs es sensible a la capa subyacente SAM.
- Se observó que la T (m) puede controlarse eficazmente mediante la elección de la composición de SAM y/o la densidad de embalaje.
- Cuantificó el impacto de diferentes SAMs en el comportamiento de transición de fase de las superposiciones lipídicas.
Conclusiones:
- La composición y la densidad de embalaje del SAM subyacente influyen significativamente en la temperatura de transición de fase de los HBM.
- Esto proporciona un método para afinar las propiedades de las membranas de doble capa híbrida.
- Los hallazgos son cruciales para el diseño de superficies funcionalizadas y la comprensión de la biofísica de la membrana.
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