Preparation and Physicochemical Characterization of Solid Dispersion of Irbesartan with Poloxamer 188

AIM: The aim of the present study was to prepare and characterize the solid dispersion of poorly soluble drugs irbesartan with hydrophilic polymer poloxamer 188 by solvent co-evaporation technique. METHODS: The ratio of irbesartan to poloxamer 188 in solid dispersion system was 1:0.5; 1:1; and 1:3. Physicochemical properties characterization was analyzed by X-ray powder diffraction, Fourier-transform infrared (FT-IR) spectroscopy, differential thermal analysis, and scanning electron microscopy (SEM). The in vitro dissolution rate profile of solid dispersion was performed by Type II United States Pharmacopeia dissolution testing apparatus. RESULTS: The results of the X-ray powder diffraction pattern showed that the degree of crystallinity of irbesartan crystalline phase reduced in a solid dispersion system. FT-IR spectra indicate that there is no chemical interaction between irbesartan and poloxamer 188 in a solid dispersion system. SEM microscopy demonstrated a homogenous phase of a solid dispersion system with distinct crystal habit. In general, in vitro dissolution rate of all solid dispersions was higher than intact irbesartan. The highest percentage of dissolved irbesartan was the solid dispersion of irbesartan-poloxamer 188 (1:0.5 w/w). CONCLUSIONS: The study concludes that the solid dispersion can be applied to improve the dissolution rate of irbesartan.