Design of a Physical and Nontoxic Crosslinked Poly(Vinyl Alcohol) Hydrogel
Titel:
Design of a Physical and Nontoxic Crosslinked Poly(Vinyl Alcohol) Hydrogel
Auteur:
Oviedo, I. Rojas Mendez, N. A. Noguez Gomez, M. P. Gomez Rodriguez, H. Cardenas Martinez, A. Rubio
Verschenen in:
International journal of polymeric materials
Paginering:
Jaargang 57 (2008) nr. 12 pagina's 1095-1103
Jaar:
2008-12
Inhoud:
Controlled delivery matrices are an alternative available to provide a better administration of drugs. Hydrogels have been used to produce these matrices due to the control of absorption and desorption rates of water into their molecular structure, which allows us to obtain various delivery profiles. Poly(vinyl alcohol) (PVA), a candidate matrix material, was physically modified through a solvation-desolvation process with acetone to change its crystallinity. Tolbutamide is a poorly water-soluble drug with a dissolution-rate-limited bioavailability. Thus, it was used as a model for this methodology. This physical method introduces crosslinks, which decrease the crystallinity of PVA in the order of 8% and has the advantage that there is no residual toxic chemical present in the hydrogel. Dissolution studies, carried out with the PVA-hydrogel (H) loaded with tolbutamide, allow us to state that 78% of drug release takes place in about 24 h which contrasts with the dissolution curves of tablets of tolbutamide and tolbutamide mixed with the PVA as powder both of which were used as comparative preparations.