ABSTRACT:
The main purpose of this work was to formulate and evaluate co-surfactant free self-emulsifying drug delivery system (SEDDS) for poorly soluble drug for enhance oral bioavailability. Drug solubility was assessed in different oils and surfactants. Capmul MCM was selected as an oil phase and surfactants (Tween 20, Tween 60, Tween 80 and Cremophor EL) in specific combination at defined ratios (Km) were used. Percent transmittance (%T) study was performed to identify the efficient self-emulsifying formulation. Those formulations which showed higher value for %T were evaluated for droplet size analysis, zeta potential, viscosity, refractive index, self-emulsification time and dilution at different pH. In-vitro dissolution was preformed and compared with marketed formulation. Also oral bioavailability of the optimized formulation was assessed and data was compared with the marketed conventional formulation. Capmul MCM oil showed good solubility for the selected drug i.e Ramipril. Most of the hydrophilic surfactant showed good solubility for the drug and were selected for further emulsification studies. % T studies revealed that chemical structure of the oil and surfactant combinations are important in self-emulsification. Optimized formulation for in vitro dissolution and bioavailability assessment was composed of Ramipril (10 mg), Tween 80 (160mg), Cremophor EL (640mg) and Capmul MCM as oil (200mg). The dissolution profile for Ramipril from SEDDS was significantly higher than the conventional capsule (Ramistar®). The bioavailability of Ramipril from SEDDS resulted in increase bioavailability as compared with the conventional capsule. Our studies illustrated the potential use of co-surfactant free SEDDS for the delivery of hydrophobic compounds, such as Ramipril by the oral route for enhance oral bioavailability.