Development of self-microemulsifying drug delivery system of mebendazole by spray drying technology: Characterization,in vitro and in vivo evaluation

In this study, a novel liquid self-microemulsifying drug delivery system (SMEDDS) containing mebendazole was formulated and further developed into a solid form by a spray drying method using Aerosil 200 as the solid carrier. The optimum liquid SMEDDS consisted of Labrafil 2125 CS, Tween 20, and Maisine 35-1 as the oil phase, the surfactant, and the cosurfactant, respectively. The formulated SMEDDS was completely emulsified or dispersed within a minute. All formulations were dissolved within 1 h using 0.1 N HCl as dissolution medium, whereas pure drug was less significantly dissolved in this time period. The droplet size was found to be within 250 nm for solid forms of SMEDDS. Solid state characterization was performed by scanning electron micrograph, differential scanning calorimetry, and X-ray powder diffraction. After oral administration to Wistar rats, mebendazole in the solid SMEDDS resulted in the significant improvement in bioavailability compared with that of pure drug analyzed by RP-HPLC. The optimized formulation showed 24.87 folds increase in bioavailability as compared to pure drug and 8.39 folds increase in bioavailability in comparison to marketed tablet of mebendazole. The optimized batch has found to be 3.1726 years of shelf life. In conclusion, the solid SMEDDS is a promising solid dosage form for poorly water-soluble and low bioavailability drugs.