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Dissolution rate and stability study of flavanone aglycones, naringenin and hesperetin, by drug delivery systems based on polyvinylpyrrolidone (PVP) nanodispersions.

OBJECTIVE
To study the dissolution behavior, the release mechanism and the stability of nanodispersion system of aglycones with PVP.


METHODS
The nanodispersion system of polyvinylpyrrolidone (PVP)/naringenin-hesperetin was prepared using the solvent evaporation method. The chemical stability (compatibility) of naringenin and hesperetin in the prepared dispersions was studied under accelerated conditions for 3 months. The evaluation of physical stability was performed by X-ray diffraction analysis (XRD) and by comparing the dissolution profile before and after storage at high temperature and moisture (40 masculineC, RH 75%).


RESULTS
The dissolution rate of naringenin and hesperetin released was dramatically increased in the nanodispersion system of PVP/naringenin-hesperetin (80/20, w/w). The release mechanism of both flavanone aglycones was better described by the diffusion model (Higuchi model). Also it was found that the rate-limiting step that controlled the release of naringenin and hesperetin in the nanodispersion system was dissolution of the carrier (PVP).


CONCLUSIONS
During accelerated degradation analysis, for 3 months at high temperature and moisture, PVP nanodispersion system showed enhanced chemical compatibility and physical stability. The physical evaluation (obtained from XRD analysis) of PVP/naringenin-hesperetin (80/20, w/w) in the selected storage conditions did not show any crystallization of flavanone aglycones in the PVP nanodispersion system or any change in their release profile.