Enhanced transdermal deposition and characterization of quercetin-loaded ethosomes

We sought to evaluate the transdermal permeation potential of quercetin-loaded ethosomes. Quercetin-loaded ethosomes were prepared and characterized with regard to particle size, loading efficiency, stability, and in vitro skin permeation. The optimized formulation of ethosomes was confirmed using 2% egg phosphatidylcholine and hydrated 20% ethanol. After quercetin was applied using this formulation, the stability of the ethosomes was determined when loaded with up to 0.04% quercetin. We observed that loading efficiency was improved with increasing concentrations of quercetin. Ethosomes loaded with 0.04% quercetin showed both the greatest loading efficiency (63.9%+/- 6.0%) and an optimal size range (132 +/- 32 nm). Ethosomes loaded with quercetin were superior in skin permeation ability (29.5 +/- 7.0 mu g/cm(2)) compared to either ethanolic solution or liposomes. Therefore, we concluded that quercetin-loaded ethosomes increased the skin delivery of quercetin. Our results suggest that quercetin-loaded ethosomes may enhance the effect of cosmetic materials.