Preparation and physicochemical characterization of surfactant based solid dispersions of ezetimibe.

Solid dispersions of the poorly water-soluble drug ezetimibe were prepared with a surfactant, Pluronic 188 in different ratios and characterized by FTIR, XRD, DSC and dissolution studies. The melting method was employed to prepare the solid dispersions whereas a physical mixture (1:3) was prepared by co-grinding the individual components in a mortar. Physical studies demonstrated a significant reduction in crystallinity with a possibility of presence of amorphous character of drug in the solid dispersions of ezetimibe. Among all binary systems studied, the 1:3 proportion of ezetimibe: Pluronic 188 showed fastest dissolution rate (DE90: 73.38% +/- 3.95) suggesting optimum ratio of the surfactant used.

Development and characterization of bicalutamide-poloxamer F68 solid dispersion systems.

The objective of the present work was to improve the dissolution rate of a poorly water-soluble drug, bicalutamide, by a solid dispersion technique. The solid dispersion systems of bicalutamide were prepared with poloxamer F68 in 1:1, 1:3, and 1:5 ratios using the melting method. The interaction of drug with polymer was evaluated by TLC, FTIR, and powder XRD. The results of powder XRD showed a significant decrease in the crystallinity of drug in the binary systems of bicalutamide. All binary systems of bicalutamide showed faster dissolution than pure drug alone (p < 0.001). However, among all binary systems studied, 1:1 proportion of bicalutamide : poloxamer was found to be excellent for dissolution enhancement (DP30: 99.98% +/- 3.9) of bicalutamide. The higher ratios of poloxamer F68 (1:3 and 1:5) had retarded the release of drug from their corresponding binary systems which might be due to its gelling property in higher concentration.