Release behavior of cilostazol according to the fabrication methods and ratio of HPMC/PVP

In this study, we manufactured a polymer blend, using hydroxypropyl methylcellulose (HPMC) and polyvinylpyrrolidone (PVP), by spray drying method to improve the characteristics of polymers. This polymer blend was used to improve the drug delivery of cilostazol, a phosphodiesterase inhibitor that decreases serum triglycerides, is a direct arterial vasodilator, and inhibits platelet aggregation and smooth muscle cell proliferation. Compatibility with this drug was achieved when the polymer blend of HPMC and PVP were spray dried. Various ratios of the two ingredients were blended to determine optimum release rate of this poorly soluble drug. Cilostazol blended with different ratios of HPMC and PVP was analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to confirm surface morphology and combination of drug and polymer. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) were conducted to confirm thermodynamic properties and chemical structure change, respectively. Change in the drug release of cilostazol was expected by adjusting the HPMC and PVP blend ratio in gastric juice (pH 1.2).