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Poliéteres poliquetales multifuncionales ramificados: la variación de la estructura del grupo cetal permite un
Rajesh A Shenoi1, Jayaprakash K Narayanannair, Jasmine L Hamilton
1Centre for Blood Research and Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z3.
Journal of the American Chemical Society
|August 22, 2012
Resumen
Los investigadores desarrollaron nuevos polímeros biodegradables llamados polihidroxiéteres cetálicos (PKHEs) con tasas de degradación sintonizables para la nanomedicina avanzada. Estos nanomateriales multifuncionales muestran una excelente biocompatibilidad y una descomposición controlada dentro de las células.
Área de la Ciencia:
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Ciencia de los materiales Ciencia de los materiales.
- La nanomedicina es la nanomedicina.
Sus antecedentes:
- El desarrollo de nanomateriales multifuncionales, biocompatibles y biodegradables es crucial para la nanomedicina dirigida.
- Los materiales existentes a menudo carecen de un control preciso sobre los perfiles de degradación y la capacidad de respuesta a los estímulos.
Objetivo del estudio:
- Para sintetizar y caracterizar una nueva clase de poliéteres dendríticos polietálicos multifuncionales (hidroxiéteres polietálicos - PKHEs).
- Para lograr un control sin precedentes sobre las tasas de degradación de polímeros en solución y dentro de las células.
- Evaluar la biocompatibilidad y el potencial de las PKHEs para aplicaciones en la nanomedicina.
Principales métodos:
- La polimerización multibranqueante de apertura de anillo aniónico de nuevos monómeros cetálicos de tipo AB(2).
- Funcionalización del polímero con grupos de azida y amina.
- Estudios de hidrólisis a pH ligeramente ácido para determinar la cinética de la degradación.
- Estudios de degradación celular utilizando microscopía confocal.
- Evaluaciones de biocompatibilidad (ensayo MTS, pruebas de compatibilidad sanguínea).
Principales resultados:
- Se ha sintetizado con éxito PKHEs compactos de alto peso molecular con propiedades sintonizables.
- Control preciso demostrado sobre las tasas de degradación de polímeros (de minutos a cientos de días) basado en la estructura del grupo cetal y la hidrofobidad.
- Se confirmaron perfiles de degradación similares dentro de las células vivas, lo que lleva a la entrega citosólica de marcadores.
- Las PKHEs y sus productos de degradación mostraron una alta biocompatibilidad y compatibilidad con la sangre.
Conclusiones:
- Esta nueva clase de PKHEs biodegradables ofrece una degradación ajustable, lo que permite un control preciso para la nanomedicina.
- La biocompatibilidad demostrada y la degradación intracelular hacen que las PKHEs sean muy prometedoras para la administración de fármacos dirigidos y otras aplicaciones nanomédicas.
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