Artigo
Multicomponent complex formation between pyrimethamine, cyclodextrins and water-soluble polymers
Fecha
2011-10-01Registro en:
Brazilian Archives of Biology and Technology. Instituto de Tecnologia do Paraná - Tecpar, v. 54, n. 5, p. 965-972, 2011.
1516-8913
S1516-89132011000500014.pdf
S1516-89132011000500014
10.1590/S1516-89132011000500014
WOS:000297761500014
Autor
Rodrigues, Leticia Norma Carpentieri [UNIFESP]
Issa, Michelle Georges
Asbahr, Ana Carolina Cavassin
Silva, Marco Aurélio Carvalho
Ferraz, Humberto Gomes
Institución
Resumen
The combined effect of hydroxypropyl-β-cyclodextrin (HPβCD) and polyvinylpyrrolidone (PVP) or sodium carboxymethylcellulose (CMC) on the solubility of pyrimethamine (PYR) was studied. Equimolar PYR-HPβCD solid systems, in the presence or the absence of 0.25% (w/v) PVP or 0.10% (w/v) CMC were prepared by coevaporation or freeze-drying, and characterized by differential scanning calorimetry, X-ray diffraction analysis and dissolution profile. Phase-solubility analysis was used to investigate the interactions in aqueous solution between PYR and HPβCD, in the absence or presence of polymers, which showed a linear increase of PYR solubility depending on the concentration of HPβCD. The presence of polymer did not alter the stoichiometry of the complexes. DSC results were indicative of complexation, due to the loss of the characteristic endothermic peak of PYR. X-ray diffraction analysis confirmed the DSC results. Binary and ternary complexes showed higher dissolution rate when compared with the pure drug.