Preparation of Solid Self-Emulsifying Drug Delivery System of Manidipine Hydrochloride

The ability of self-emulsifying drug delivery system (SEDDS), which is a mixture of oils, surfactants and co-surfactants, to improve dissolution rate of a poorly water-soluble drug, manidipine hydrochloride (MDP), was evaluated in this study. Liquid form of SEDDS containing caprylic/capric glyceride, polyoxyl 35 castor oil, and diethylene glycol monoethyl ether at a weight ratio of 1:1:8 was converted to solid SEDDS by adsorption on to different solid carriers, i.e., Aerosil® 200 and Sylysia® 320. The results demonstrated that the solid carrier of at least 50% (w/w) was required to adsorb liquid SEDDS containing MDP. The results from powder X-ray diffraction, differential scanning colorimetry and scanning electron microscopy showed that MDP in solid SEDDS formulations was in amorphous form while a crystalline form was observed only in MDP raw material and its physical mixture. The in vitro dissolution of MDP from solid SEDDS using Sylysia® 320 was higher than that using Aerosil® 200 as a solid carrier. In summary, the solid SEDDS could be used as a carrier to improve the dissolution of MDP, a poorly water-soluble drug.