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Microtesla SABRE permite una polarización de espín nuclear de 10% de nitrógeno-15 y una polarización de spin nuclear

Thomas Theis¹, Milton L Truong, Aaron M Coffey

¹Department of Chemistry, Duke University , Durham, North Carolina 27708, United States.

Journal of the American Chemical Society

|January 14, 2015

Resumen

El parahidrógeno hiperpolariza eficientemente el nitrógeno-15 en piridina y nicotinamida utilizando "amplificación de señal por intercambio reversible" (SABRE) en un escudo magnético. Este método "SABRE en escudo permite la transferencia de alineación a los heteronúcleos" (SABRE-SHEATH) ofrece una hiperpolarización rentable para diversas aplicaciones.

Área de la Ciencia:

Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopia de Resonancia Magnética Nuclear (RMN)
Química cuántica es la química cuántica.
La biofísica es la biofísica.

Sus antecedentes:

Las técnicas de hiperpolarización mejoran significativamente la sensibilidad de la señal de RMN.
El nitrógeno-15 (15N) es un núcleo crucial para las imágenes moleculares y los estudios metabólicos.
Los métodos actuales de hiperpolarización pueden ser complejos y costosos.

Objetivo del estudio:

Demostrar una eficiente hiperpolarización del espín nuclear del nitrógeno-15 en moléculas biológicamente relevantes.
Introducir un método de hiperpolarización novedoso y rentable.
Explorar el potencial de esta técnica para aplicaciones in vivo.

Principales métodos:

Utilizando parahidrógeno y "amplificación de señal por intercambio reversible" (SABRE) en campos de microtesla.
Realizar SABRE dentro de un escudo magnético para lograr una transferencia de polarización de espín eficiente.
Transferencia de muestras hiperpolarizadas a un espectrómetro de RMN convencional para la detección de señales.

Principales resultados:

Se lograron mejoras de ∼30,000 veces y ∼20,000 veces en (15) señales de RMN de piridina y nicotinamida, respectivamente.
Se alcanzaron polarizaciones de espín nuclear de ∼10% y ∼7% para piridina y nicotinamida a 9,4 T.
Se demostró la efectividad del método "SABRE en escudo permite la transferencia de alineación a los heteronúcleos" (SABRE-SHEATH).

Conclusiones:

SABRE-SHEATH proporciona un enfoque simple y rentable para la hiperpolarización de heteronúcleos como el (15) N.
El método ofrece ventajas potenciales para la RMN / IRM in vivo debido a la larga vida útil de la hiperpolarización y las señales de fondo mínimas.
La fácil discriminación por desplazamiento químico de diferentes especies aumenta su utilidad para estudios biológicos.

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