Design and Development of Self Microemulsyfying Drug Delivery System of Olmesartan Medoxomil Smita D Patel*, M R Patel, K R Patel

Abstract

Olmesartan Medoxomil is poorly water soluble drug. It comes into the BCS II drug. Hence oral bioavailability of Olmesartan Medoxomil is less (26%). The purpose of this study is to develop novel dosage form of the self-microemulsifying drug delivery systems (SMEDDS) for the Olmesartan Medoxomil for enhancing its solubility hence the oral bioavailability. Before the formulation of SMEDDS, solubility study was performed in different excipients and select excipients on basis of solubility of Olmesartan Medoxomil. Microemulsion region was decided by preparing ternary phase diagram. Drug excipients interaction study performed using FTIR. After preliminary study, SMEDDS formulations were prepared in Capmul MCM NF (oil), Acrysol EL 135 (surfactant), and Transcutol CG (co-surfactant) by simple mixing at 40˚C. Parameters evaluated included: macroscopic evaluation, Visual assessments, self emulsification, transmittance test, particle size distribution, zeta potential, and polydispersity index and in vitro dissolution. In vitro dissolution was carried in USP apparatus II using phosphate buffer pH 6.8 at 37±0.50C with 50 rpm rotating speed. Drug release was measured by spectroscopic method. The results obtained from the solubility study, better solubility was seen in Capmul MCM NF (oil), Acrysol EL 135 (surfactant), Transcutol CG (co-surfactant). No any drug excipients interaction was seen. Optimized formulation S3 of SMEDDS was observed with smaller droplet size 16.62nm, PDI 0.178, and zeta potential −12.1mV⁵.Formulation was clear and near to 100% transmittance after dilution with Water. SMEDDS formulation showed complete release in 60 min as compared with the plain drug, which showed a limited dissolution rate. Conclusion of the study is SMEDDS Olmesartan Medoxomil oral formulations were prepared that provides excellent drug solubilisation and improved in vitro release of Olmesartan Medoxomil.

Keyword: SMEDDS, Olmesartan Medoxomil, bioavailability, in-vitro release study