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Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging
Published on: December 30, 2016
PASADENA hiperpolarización del ácido succínico para la espectroscopia de RMN y RMN
Eduard Y Chekmenev1, Jan Hövener, Valerie A Norton
1A. A. Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|March 14, 2008
Resumen
Los investigadores lograron una polarización del 13C del 20% en segundos utilizando parahidrógeno y la síntesis permite una alineación nuclear mejorada drásticamente (PASADENA) para el ácido succínico. Este método es prometedor para la hiperpolarización de otros ácidos carboxílicos y el avance de la espectroscopia metabólica.
Área de la Ciencia:
- Espectroscopia de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN) Espectroscopía de Resonancia Magnética Nuclear (RMN)
- Técnicas de hiperpolarización Técnicas de hiperpolarización
- Imágenes de imágenes metabólicas.
Sus antecedentes:
- La alineación nuclear a través de la parahidrogenación ofrece una mayor sensibilidad en la RMN.
- El estudio de los procesos metabólicos requiere sensitivas sondas moleculares.
Objetivo del estudio:
- Para lograr una alta polarización 13C en ácido succínico utilizando el método PASADENA.
- Para investigar el comportamiento dependiente del pH del ácido succínico hiperpolarizado.
- Evaluar el potencial para la espectroscopia molecular del metabolismo.
Principales métodos:
- Utilizó el método PASADENA para la hiperpolarización del ácido 1-13C-succínico-d2.
- Se observaron múltiplos de 13C de alto campo en función del pH.
- pH optimizado a aproximadamente 3 para la adición de parahidrógeno y transferencia de orden de giro.
Principales resultados:
- Logró aproximadamente un 20% de polarización 13C en segundos.
- Se observó una ampliación pronunciada de la línea de C1 cerca de los valores de pK.
- Los tiempos de relajación de la red de giro C1 medidos fueron de 27 s (H2O) y 56 s (D2O) a pH neutro y 4.7 T.
Conclusiones:
- El método PASADENA hiperpolariza eficazmente el ácido succínico.
- pH influye significativamente en las características espectrales y la transferencia de orden de giro.
- La técnica muestra potencial para generalizar a otros ácidos carboxílicos y avanzar en la espectroscopia metabólica in vivo.
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