No abstract

Liquiritin and its aglycone, liquiritigenin are flavonoid found in licorice that show anti-oxidant and anti-aging properties. In this study, ethosomes loaded with hydrophobic liquiritigenin or liquiritin were prepared as a transdermal delivery system. The particle size, entrapment efficiency, and skin permeability of ethosomes were evaluated. Ethosome containing liquiritigenin was stable up to 2 mM and ethosome containing liquiritin was stable up to 0.75 mM concentration. The particle size of ethosomes containing 0.75 mM liquiritigenin and liquiritin was 143.85 and 158.90 nm, respectively and the entrapment efficiency was 47.51 and 54.61%, respectively. The entrapment efficiency was improved with increasing concentrations of drugs. Ethosomes loaded with liquiritigenin or liquiritin were superior in skin permeation ability compared to that of 20% ethanol solution and conventional liposomes. These results suggest that ethosomes containing 0.50 mM liquiritigenin or liquiritin are effective for the skin permeation and may be used as an antiaging and antioxidant ingredient in cosmetic formulation.