Abstract

SOLUBILITY ENHANCEMENT OF AZILSARTAN BY SELFEMULSIFYING LIPID FORMULATIONS

Dr. M. Sunitha Reddy*, Senigarapu Soumya and S. Muhammad Fazal Ul Haq

ABSTRACT

Azilsartan is a BCS class II drug with poor aqueous solubility. The present work mainly emphasized on the enhancement of solubility of Azilsartan by developing Self Emulsifying Lipid Formulations. The solubility of Azilsartan was determined in various lipid excipients by UV Spectroscopy analysis. Based on the solubility data and IR studies the excipients were selected. Labrafac Lipophile WL 1349(oil), Tween 80 (Surfactant) and Polyethylene glycol 400 (PEG 400) were Selected as co-surfactants and formulation were developed. A series of Pseudoternary phase diagrams were constructed by water titration method to determine the microemulsion region. Various compositions of oil and surfactant mixture were titrated with water to determine the limit of emulsification and microemulsion region. Two selected formulations were further evaluated for self emulsification time, phase separation, Thermodynamic stability studies, Droplet size distribution and zeta potential. None of these exhibited phase separation and drug precipitation. Thermo dynamic stability studies were satisfactory. Effect of dilution did not exhibit phase separation. Based on the above experiments, two formulations were optimized. Using the optimized self micro emulsifying mixture, Azilsartan loaded Liquid SELFS was prepared, evaluated for their selfmicroemulsification tendency and characterized. In vitro drug release studies showed nearly 83.42% drug release in first 60 minutes of dissolution by LLT3P1 liquid SELFs. The in-vitro release profiles of two formulations were good. They showed a significant increased rate of dissolution, when compared with the plain azilsartan drug. Among the two formulations, LLT3P1-2(2:8) formulation was found to exhibit better drug release with average droplet size of 119.1nm and zeta potential of -7.94 mV. The self emulsifying Lipid formulations exhibited improved dissolution characteristics of an Azilsartan. The present studies indicates that SELFs can be potentially used a drug delivery system for delivering poorly water soluble drugs.

Keywords: Azilsartan, Oils, Surfactants, Co-surfactants, Pseudo ternary phase diagram, solubility study.