Combination of eudragit EPO with poloxamers for improved solubility and dissolution of Zafirlukast: An evaluation of solid dispersion formulations.

This study investigated the effect of solid dispersions (SD) on solubility and release of Zafirlukast (ZA) by physical mixture (PM), solvent evaporation (SE) and kneading method (KM) with Eudragit EPO (EPO) as binary component and Poloxamer 188 (P188) and Poloxamer 407 (P407) as ternary components. The binary and ternary systems caused an increase of 322 folds and 356 folds in aqueous solubility of ZA, respectively. Formulations were characterized for solubility, FTIR, PXRD, DSC, SEM and dissolution studies. P407 was found to be an excellent solubility booster in combination with EPO. It was concluded that solubility and dissolution rate of ZA increased significantly when SD of the ZA was prepared by solvent evaporation method (1:7 ratio) using 15% P407 as ternary component.

Improvement of solubility, dissolution and stability profile of artemether solid dispersions and self emulsified solid dispersions by solvent evaporation method.

The purpose of this study was to investigate changes in the water solubility of artemether; a poorly soluble drug used for the treatment of malaria. Different solid dispersions (SDs) of artemether were prepared using artemether and polyethylene glycol 6000 at ratio 12:88 (Group 1), self-emulsified solid dispersions (SESDs) containing artemether, polyethylene glycol 6000, cremophor-A-25, olive oil, hydroxypropylmethylcellulose and transcutol in the ratio 12:75:5:4:2:2, respectively (Group 2). SESDs were also prepared by substituting cremophor-A-25 in Group 2 with poloxamer 188 (noted as Group 3). Each of these preparations was formulated using physical mixing and the solvent evaporation method. Aqueous solubility of artemether improved 11-, 95- and 102-fold, while dissolution (in simulated gastric fluid) increased 3-, 13- and 14-fold, for formulation groups 1, 2 and 3, respectively. X-ray diffraction patterns of SDs indicated a decrease in peak intensities at 10° implying reduced artemether crystallinity. Scanning electron micrographs invariably revealed embedment of artemether by various excipients and a glassy appearance for solvent evaporated mixtures for all three formulation Groups. Our findings indicate improved hydrophilic interactions for drug particles yield greater solubility and dissolution in the following order for artemether formulating methods: solvent evaporation mixtures > physical mixtures > pure artemether.