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Hyperpolarized 13C Metabolic Magnetic Resonance Spectroscopy and Imaging
Published on: December 30, 2016
Nuevos agentes de contraste hiperpolarizados para la resonancia magnética por 13C-MRI a partir de la
Francesca Reineri1, Alessandra Viale, Giovanbattista Giovenzana
1Dipartimento di Chimica IFM, Università di Torino, Via P. Giuria 7, 10125 Torino, Italy.
Journal of the American Chemical Society
|October 17, 2008
Resumen
Dos nuevos derivados de alquino son sustratos efectivos para la para-hidrogenación, produciendo alquenos hiperpolarizados. El derivado simétrico resultante es soluble en agua, lo que permite aplicaciones de resonancia magnética in vivo.
Área de la Ciencia:
- Los agentes de contraste de resonancia magnética hiperpolarizados son agentes de contraste de resonancia magnética hiperpolarizados.
- La síntesis orgánica es la síntesis orgánica.
- La química cuántica es una química cuántica.
Sus antecedentes:
- La para-hidrogenación es un método para producir compuestos hiperpolarizados.
- Las moléculas hiperpolarizadas mejoran la sensibilidad de la resonancia magnética.
- Los sustratos alquinos se exploran por su potencial para generar nuevos agentes hiperpolarizados.
Objetivo del estudio:
- Para sintetizar y evaluar los derivados de alquina como sustratos para la para-hidrogenación.
- Desarrollar un marco teórico que explique los mecanismos de para-hidrogenación.
- Evaluar la idoneidad de los compuestos hiperpolarizados resultantes para aplicaciones de RMN.
Principales métodos:
- Síntesis de derivados de alquina con cadenas oligooxieetilénicas.
- Reacciones de para-hidrogenación utilizando las técnicas ALTADENA y PASADENA.
- Modelado teórico de los efectos inducidos por el para-hidrógeno.
- In vitro (13) Imágenes de C-MR en diferentes disolventes.
- Ciclos de campo para una mejor adquisición de señales.
Principales resultados:
- Dos derivados de alquina demostraron un buen rendimiento del sustrato en la para-hidrogenación.
- Se lograron altos rendimientos de los alquenos hiperpolarizados correspondientes.
- Se desarrolló una teoría para explicar los efectos de para-hidrogenación en alquinos simétricos y asimétricos.
- El producto hidrogenado simétrico exhibió una buena solubilidad en agua.
- Se realizó con éxito in vitro (13) imágenes de C-MR en soluciones acuosas.
Conclusiones:
- Las cadenas oligooxieetilénicas imparten solubilidad en agua a los derivados para-hidrogenados de alquino.
- El producto soluble en agua facilita la separación y la preparación para la resonancia magnética in vivo.
- Estos hallazgos apoyan el desarrollo de nuevos agentes de contraste hiperpolarizados para imágenes médicas.
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