Document details

Made available in DSpace on 2018-12-11T16:43:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-09-01

Cyclodextrins (CDs) and meglumine (MEG) are pharmaceutical excipients widely used to improve solubility of poorly water-soluble drugs. The purpose of this work was to study the effect of CDs or MEG on the internal microstructure of soya oil–based O/W microemulsions (MEs) and on the modulation of the solubility and release rate of Class II model hydrophobic drugs, sulfamerazine and indomethacin. The pseudoternary phase diagrams revealed that higher proportions of oil phase, as well as the presence of β-cyclodextrin (ßCD), methyl-ßCD, and MEG, favored the incorporation of the drugs. The conductivity studies, particle size, and zeta potential analysis showed that the O/W ME structure remained unaffected and that the ME presented reduced droplet sizes after the incorporation of the ligands. The drug-component interactions were assessed by proton nuclear magnetic resonance studies. The highest incorporations of sulfamerazine (35.6 mg/mL) and indomethacin (73.1 mg/mL) were obtained with the ME with W = 5%, MEG and W = 1.8% ßCD in a phosphate buffer solution of pH 8, respectively. In addition, the ligands in ME significantly enhanced the released amount of the drugs, probably due to a solubilizing effect that facilitates the drug to penetrate the unstirred water layer adjacent to membranes.

Unidad de Investigación y Desarrollo en Ciencia y Tecnología Farmacéutica (UNITEFA-CONICET) Departamento de Farmacia Facultad de Ciencias Químicas-Universidad Nacional de Córdoba Ciudad Universitaria

UNESP-Universidade Estadual Paulista Faculdade de Ciências Farmacêuticas

UNESP-Universidade Estadual Paulista Faculdade de Ciências Farmacêuticas