Self Microemulsifying Immediate Release Tablet of Azilsartan for Enhanced Dissolution

Abstract

Azilsartan has solubility problem which leads to low dissolution and hence bioavailability, hence it is necessary to improve solubility of azilsartan. Objective of study was to develop self micro emulsifying tablet of azilsartan to enhance dissolution. Liquid self micro emulsifying drug delivery system (SMEDDS) was prepared using ethyl oleate, Tween 80 and Transcutol P as oil, surfactant and co-surfactant respectively. Microemulsion region was predicted by constructing a pseudo-ternary phase diagram containing a different proportion of oil, surfactant, and co-surfactant. Liquid SMEDDS was then converted to solid form (S-SMEDDS) by adsorption technique using Neusilin US2 as a solid carrier and evaluated for various pre-compression micromeritic properties. This S-SMEDDS were then compressed into immediate release tablet. Developed tablet of azilsartan were reconstituted and evaluated for % Transmittance, globule size, zeta potential. Tablets were also evaluated for post compression parameters, in-vitro dissolution study, DSC, XRD and FTIR. Reconstitution properties of self emulsifying tablet showed spontaneous micro emulsification with globule size 210 nm and-37 mV zeta potential. From results of in-vitro dissolution study, it was found that the release of azilsartan was significantly increased as compared with pure azilsartan. Study concluded that dissolution of azilsartan can be significantly improved by formulating it in to self emulsifying tablet for getting improved oral bioavailability.