Role of solid carriers in pharmaceutical performance of solid supersaturable SEDDS of celecoxib

Self emulsifying drug delivery system (SEDDS) has been increasingly used for improving the oral bioavailability of poorly water soluble drugs. SEDDS can be solidified by adsorbing them on different solid carriers. In the present study, the impact of properties of solid carrier on drug release profile from solid SEDDS was investigated. Celecoxib (CEL) loaded supersaturable SEDDS (S-SEDDS) was prepared and optimized by using optimal response surface design. Optimum composition of S-SEDDS corresponded to 10:45:45% v/v ratio of oil (Capryol 90), surfactant (Tween 20) and cosurfactant (Transcutol HP) with Soluplus (40 mg) as precipitation inhibitor. Different grades of silicon dioxide were selected based on their properties like surface area, porosity and hydrophobicity-hydrophilicity, and used for preparation of solid S-SEDDS (SS-SEDDS) by adsorption method. All SS-SEDDS formulations in release studies, gave droplet size, PDI and zeta potential similar to S-SEDDS. The percent drug release after 120min from CEL powder, S-SEDDS and SS-SEDDS with Sylysia 350 fcp, Aerosil 300 Pharma, Aerosil 200 Pharma and Aerosil R 972 Pharma was found to be 0.58%, 100%, 38.44%, 9.63%, 2.53% and 5.99%, respectively. Drug release profiles were compared by using model independent methods. The differential drug release behavior of SS-SEDDS was attributed to the different physico-chemical properties of solid carriers. SS-SEDDS with Sylysia 350 fcp showed higher drug release and greater dissolution efficiency. Oral bioavailability study also demonstrated 2.34 fold increase in Cmax and 4.82 fold increase in AUC (0-24h) when compared with CEL powder. This study highlights the rational for selection of solid carriers in the formulation development of solid SEDDS.