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A New Straightforward Method for Lipophilicity (logP) Measurement using 19F NMR Spectroscopy
Published on: January 30, 2019
Orientación del colesterol fluorado en las bicapas lipídicas analizadas por el cálculo del tensor 19F y RMN en estado
Nobuaki Matsumori1, Yusuke Kasai, Tohru Oishi
1Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan. matumori@ch.wani.osaka-u.ac.jp
Journal of the American Chemical Society
|March 18, 2008
Resumen
El colesterol 6-F exhibe una dinámica de membrana y una orientación similares al colesterol. La introducción de flúor en la posición C6 no altera significativamente el colesterol.
Área de la Ciencia:
- La biofísica es la biofísica.
- Biofísica de las membranas Biofísica de las membranas.
- La bioquímica es la bioquímica.
Sus antecedentes:
- El colesterol 6-F muestra propiedades biológicas e interfaciales similares al colesterol.
- Imita la actividad del colesterol en sistemas como la anfotericina B y las balsas de lípidos.
Objetivo del estudio:
- Para determinar la orientación molecular y la dinámica del colesterol 6-F en las bicapas de DMPC.
- Evaluar la idoneidad del colesterol 6-F como sonda molecular para estudios de membranas.
Principales métodos:
- Espectroscopia de RMN 19F de estado sólido, incluida la anisotropía de desplazamiento químico (CSA).
- 2H experimentos de RMN y de doble resonancia de eco de rotación C-F (REDOR).
- Cálculos químicos cuánticos para el análisis tensorial 19F CSA.
Principales resultados:
- El eje de rotación del colesterol 6-F es paralelo a su estructura molecular, similar al colesterol.
- El parámetro de orden molecular del colesterol 6-F es de aproximadamente 0,85, comparable al colesterol.
- Los cálculos teóricos ayudaron a determinar los ejes principales de 19F CSA.
Conclusiones:
- La sustitución de flúor en C6 no afecta significativamente la dinámica del colesterol en las membranas del DMPC.
- El colesterol 6-F sirve como un análogo confiable para el colesterol en estudios de membrana.
- La combinación de cálculos cuánticos con RMN 19F en estado sólido es efectiva para analizar sistemas de membrana.
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