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Heteronucleación inducida por polímeros del ácido tolfenámico: investigación estructural de una pentamorfa
Vilmalí López-Mejías1, Jeff W Kampf, Adam J Matzger
1Department of Chemistry and the Macromolecular Science and Engineering Program, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, USA.
Journal of the American Chemical Society
|April 2, 2009
Resumen
El ácido tolfenámico, un fármaco antiinflamatorio no esteroide (AINE), exhibe al menos cinco formas sólidas distintas, lo que desafía las suposiciones anteriores. Estos nuevos polimorfos fueron descubiertos utilizando el cribado de heteronucleatización inducida por polímeros (PIHn).
Área de la Ciencia:
- Química del estado sólido.
- Ciencia de los materiales ciencia de los materiales.
- La cristalografía es una técnica de cristalografía.
Sus antecedentes:
- El ácido tolfenámico (AT) es un fármaco antiinflamatorio no esteroide (AINE).
- Anteriormente se creía que el TA sólo existía en dos formas polimórficas (dimórficas).
- Comprender las propiedades del estado sólido es crucial para el desarrollo farmacéutico.
Objetivo del estudio:
- Para investigar el polimorfismo en estado sólido del ácido tolfenámico.
- Para explorar la utilidad de la heteronucleación inducida por polímeros (PIHn) para el cribado de polimorfos.
- Para caracterizar el complejo comportamiento en estado sólido de TA.
Principales métodos:
- Utilizó la heteronucleación inducida por polímeros (PIHn) para el cribado de polimorfos.
- Se emplearon técnicas avanzadas de cristalografía para la caracterización.
- Cambios conformacionales analizados y desorden molecular.
Principales resultados:
- Se han identificado al menos cinco distintos polimorfos del ácido tolfenámico.
- Se observó un desorden molecular significativo y diversidad de grupos espaciales entre las formas.
- Encontró variaciones en el número de moléculas dentro de la unidad asimétrica.
- Estos polimorfos existen dentro de una estrecha ventana de energía libre (~0.3 kcal/mol).
Conclusiones:
- El ácido tolfenámico muestra una química única y compleja en estado sólido.
- PIHn es una técnica eficaz para descubrir nuevos polimorfos.
- La complejidad del TA lo convierte en un excelente punto de referencia para los modelos de predicción de la estructura cristalina.
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