Design and characterization of candesartan cilexetil oral nanoemulsion containing garlic oil

Abstract

Objective: This study was designed to prepare and characterize oil in water (o/w) nanoemulsion of candesartan cilexetil for oral administration. Preparation of candesartan cilexetil as nanoemulsion could increase its water solubility and thus could enhance its bioavailability. Methods: Aqueous titration method was used to construct the pseudo-ternary phase diagrams of nanoemulsion (NE) consisting of oil, various weight ratios of surfactant and co-surfactant (S mix), and deionized water. Different characterization techniques were conducted on the prepared nanoemulsions to obtain the optimized formula. Results: Characterizations of formula NE-4 (consists of 0.16% of candesartan cilexetil, 10% of garlic oil, 35 % of S mix (3:1) and 54.84% of deionized water) revealed the following characteristics: droplet size range (95-139 nm), polydispersity index (0.14), zeta potential value (-41.06 mV) and pH value (6.71), which are suitable for oral administration. Candesartan cilexetil in vitro release from this formula was significantly high (P<0.05) and scanning probe microscopy (SPM) study confirmed that the optimized formula (NE-4) was in nano-scale. Conclusion: Nanoemulsion formula 4 (NE-4) of candesartan cilexetil is the optimized formula and it could be a promising formula for improving the water solubility of candesartan cilaxetil.