Evaluation of Surfactant Effect on Self Micro Emulsifying Drug Delivery System (SMEDDS) of Lercanidipine Hydrochloride: Formulation and Evaluation

The aim of present research work was to develop self microemulsifying drug delivery system (SMEDDS) to improve the oral bioavailability of lercanidipine hydrochloride and to evaluate the effect of surfactant on the microemulsion existing area in the pseudo ternary diagram. Based on the solubility studies, capmul MCM C8 as oil, brij 35 and cremophor EL as surfactants, and propylene glycol as a co-surfactant were selected. Pseudo ternary phase diagrams were developed with two surfactants individually and the concentration of each surfactant on oil solubilization, existence of the monophasic area in a phase diagram was evaluated. A wider microemulsion existing area with greater amount of oil solubilization (37.0 %) and lesser globule size (15.02 nm) was observed with cremophor EL compared to brij 35. Formulation composed of lercanidipine hydrochloride (3.23 %), capmul MCM C8 (16.13 %), cremophor EL (53.76 %), and propylene glycol (26.88 %) was optimized based on the self-emulsification time, globule size analysis, and in vitro dissolution studies. Optimized formulation was evaluated further for UV spectra, cloud point, viscosity, robustness to dilution, transmission electron microscopy, and ex vivo permeation studies. SMEDDS was found to be promising in improving solubility and permeability of lercanidipine hydrochloride that are proven by in vitro dissolution and permeation studies.