European Journal of Biomedical and Pharmaceutical Sciences

UTILIZATION OF DISSOLUTION RATE IMPROVEMENT EFFECT OF DIFFERENT HYDROPHILIC POLYMERS ON ANTIPLATELET DRUG (CILOSTAZOL) VIA SOLID DISPERSION TECHNIQUE

Reda A. Mahmoud*, Wael A. Abdelhafez, Gamal Zayed, Ahmed M. Samy

ABSTRACT

Solid dispersions of a poorly water-soluble drug cilostazol in poloxamer188, polyvinylpyrrolidone (PVP-K25) and PEG 4000 were prepared by solvent evaporation technique. Physicochemical properties of the prepared systems were characterized by in vitro dissolution, powder X-ray diffraction, fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and scanning electron microscope (SEM). Cilostazol was found amorphously dispersed in solid dispersion system with the drug to poloxamer188 weight ratio of 1:5. FT-IR spectra data indicated that there was no interaction between cilostazol and the polymer. Solid dispersion prepared by the mentioned method showed an improvement of cilostazol dissolution. By comparison, solid dispersions of drug with Poloxamer188 showed distinctly superior performance in that cilostazol dissolved 67.6 ±3.1% within 120 min and the dissolution rate was at least 15 times faster than pure cilostazol. Poloxamer188 in 1:5 w/w drug/ polymer ratio could provide an effective pharmaceutical formulation method to improve the bioavailability of poorly water-soluble cilostazol.

Keywords: Cilostazol, Solid dispersion technique, Poloxamer188, Dissolution rate.