RADIOFARMACOS

VALIDACION

TABLETAS-FORMULACION

TECNECIO

BIBLIOGRAFIA NACIONAL QUIMICA

2004

Tablets containing drugs of different lipophilicity, ranitidine and cinarizine, and placebo were prepared and their in vitro behaviour was studied by dissolution and disintegration tests. [(99m)Tc]Diethylenetriamine-pentaacetic acid ([(99m)Tc]DTPA) and [(99m)Tc]ethyl cysteinate dimer ([(99m)Tc]ECD) were used as tracers of the process. Both of them were added to tablets during wet granulation. Dissolution and disintegration profiles were assessed at different pH values (1, 4 and 7). Radioactivity was evaluated in filtered samples and scintigraphic studies were carried out in gamma camera. Stability in dissolution media was confirmed for both tracers under these conditions. Dissolution and disintegration velocity constants were calculated. [(99m)Tc]DTPA proved to be an appropriate tracer for polar drugs such as ranitidine. Nevertheless, it was not a suitable tracer for lipophilic active drugs such as cinarizine. On the other hand, the most lipophilic tracer, [(99m)Tc]ECD, exhibited the opposite behaviour. Scintigraphic studies of the disintegration process did not show significant differences between placebos and tablets containing active drugs. As disintegration is a physical process it does not discriminate between chemical differences in tablet formulations. Both methods complement each other because the dissolution process can be followed when a suitable radiotracer is chosen according to the physicochemical characteristics of the active drug.

European Journal of Pharmaceutics and Biopharmaceutics v. 57, no. 2, 2004. -- p. 347-352

Elsevier

2004

Información sobre Derechos de Autor

(Por favor lea este aviso antes de abrir los documentos u objetos)

La legislación uruguaya protege el derecho de autor sobre toda creación literaria, científica o artística, tanto en lo que tiene que ver con sus derechos morales, como en lo referente a los derechos patrimoniales con sujeción a lo establecido por el derecho común y las siguientes leyes

(LEY 9.739 DE 17 DE DICIEMBRE DE 1937 SOBRE PROPIEDAD LITERARIA Y ARTISTICA CON LAS MODIFICACIONES INTRODUCIDAS POR LA LEY DE DERECHO DE AUTOR Y DERECHOS CONEXOS No. 17.616 DE 10 DE ENERO DE 2003, LEY 17.805 DE 26 DE AGOSTO DE 2004, LEY 18.046 DE 24 DE OCTUBRE DE 2006 LEY 18.046 DE 24 DE OCTUBRE DE 2006)

ADVERTENCIA - La consulta de este documento queda condicionada a la aceptación de las siguientes condiciones de uso: Este documento es únicamente para usos privados enmarcados en actividades de investigación y docencia. No se autoriza su reproducción con fines de lucro. Esta reserva de derechos afecta tanto los datos del documento como a sus contenidos. En la utilización o cita de partes debe indicarse el nombre de la persona autora.

PDF

Inglés

Artículo

doi:10.1016/j.ejpb.2003.11.003

PDF