DEVELOPMENT AND EVALUATION OF SOLID SELF NANO EMULSIFYING DRUG DELIVERY SYSTEM OF POORLY SOLUBLE OLMESARTAN MEDOXOMIL BY USING ADSORPTION ON TO SOLID CARRIER TECHNIQUE

Olmesartan medoxomil (OLM) is an angiotensin II receptor blocker antihypertensive agent. It is a highly lipophilic (log p (octanol / water) 5.55), poorly water soluble drug with absolute bioavailability of 26%.The present work aimed at formulating a solid self Nano emulsifying drug delivery system (solid-SNEDDS) for Olmesartan medoxomil with the objective of improving the aqueous solubility, dissolution and oral delivery of the drug. The solubility of OLM was determined in various vehicles like oils, surfactants and co-surfactants. Pseudoternary phase diagrams were constructed for excipients to identify the efficient self-emulsifying region and proportions of various compatible excipients for the formulation. The liquid SNEDDS was a system that consists of Olmesartan, Labrafil m1944 CS, and tween 80, polyethylene glycol 400 as a drug, oil, surfactant and co-surfactant. The optimized liquid SNEDDS was transformed into a free flowing powder by using Neusilin US2 as adsorbent. Prepared SNEDDS formulations were tested for nanoemulsifying properties and the resultant nanoemulsions were evaluated for robustness to dilution, assessment of efficiency of self emulsication, emulsification time, turbidity measurement, drug content and in-vitro dissolution. The optimized Solid-SNEDDS formulation further evaluated for heating cooling cycle, centrifugation studies and freeze thaw cycling, particle size distribution, zeta potential were carried out to confirm the stability of the formed Solid-SNEDDS. The formulation was found to show a significant improvement in terms of the drug release with complete release of drug within 60 min is selected as optimized SNEDDS formulation. The dissolution of the drug was enhanced significantly from the SNEDDS formulation as compared to plain drug.