Preparation and evaluation of valsartan by a novel semi-solid self-microemulsifying delivery system using Gelucire® 44/14
The aim of the present study was to develop a novel semi-solid self-microemulsifying drug delivery system (SMEDDS) using Gelucire® 44/14 as oil with strong solid character to improve the oral bioavailability of poorly soluble drug valsartan. The solubility of valsartan in various excipients was determined, the pseudo-ternary phase diagram was constructed in order to screen the optimal excipients, and DSC analysis was performed to evaluate the melting point of SMEDDS. The optimal drug-loaded SMEDDS formulation was consisted of 30% Gelucire® 44/14 (oil), 40% Solutol® HS 15 (surfactant), and 30% Transcutol® P (cosurfactant) (w/w) with 80 mg valsartan/g excipients. The average droplet sizes of the optimized blank and drug-loaded SMEDDS formulations were 26.20±1.43 and 33.34±2.15 nm, and the melting points of them were 35.6°C and 36.8°C, respectively.