Formulation and development of self emulsifying drug delivery system for few drugs

The purpose of this study was to develop an oral administrable SEDDS of poorly water soluble drugs of Atorvastatin calcium and Glibenclamide under Biopharmaceutical classification system of class II classification. Solubility evaluation and ternary phase diagram were carried out to select excipients of SEDDS. The composition of Atorvastatin calcium loaded and Glibenclamide loaded SEDDS was optimized using 32 facorial design. The impact of the formulation parameters on mean globule size and percentage drug load were studied by applying the analysis of variance and regression models. Several formulation and process variables were evaluated and optimized by response surface methodology. The optimum formulation was prepared by response optimizer through desirability function and the experimental values were found to be in close agreement with the predicted values. Optimized formulation was further subjected to stability studies. Optimal Atorvastatin calcium SEDDS contains sunflower oil as oil phase, labrasol as a surfactant and transcutol HP as cosurfactant (Smix) in the ratio of 67.586% oil and 52.529% % w/w Smix formulates SEDDS with lower droplet size (169.7nm), PDI (0.2), and zeta potential (-31.8 mv) and percentage drug load (87.2%) values. The optimal glibenclamide SEDDS contains peceol as oil phase, labrasol as a surfactant and transcutol HP as co-surfactant (Smix) in the ratio of 15.046% oil and 41.047% %w/w Smix formulates SEDDS with lower droplet size (172 nm), PDI (0.244), and zeta potential (-24.8mV) and percentage drug load (89.3%) values. It was concluded that the smaller particle size and drug load more the release of drug which results in better bioavailability. The in vitro evaluation parameters such as emulsification time, viscosity determination, cloud point measurement, turbidity measurement, refractive index and spectroscopic optical clarity test were performed and the results were found within the limits for all formulations of two drugs. The stability studies revealed that there was no change in particle size and percentage drug load for the two drugs after 6 months. The in vitro drug release from optimized Atorvastatin SEDDS formulation were found to be 99.75% after 90 min and 99.7% after 30 min and for Glibenclamide SEDDS. It was extremely higher in comparison to the marketed formulation and API suspension. In-vitro drug release studies closely indicate that optimized formulations obey first order kinetics and the mechanism of drug release was by fickian diffusion. The results further concluded that SEDDS can be explored as a potential drug carrier for dissolution enhancement of Atorvastatin and Glibenclamide and other poorly soluble drugs.