Mechanism of elastic vesicle enhanced skin permeation of calcein: Comparison between conventional liposomes, transferosomes and invasomes

摘要

Elastic vesicles containing different edge activators, as Sodium Cholate (Schol) or Tween (TW) (transferosomes)1,2 and various terpenes or terpene mixtures (invasomes)3, were studied. Vesicles were prepared by the thin film hydration method or by injecting the aqueous solution in an ethanolic lipid solution (Invasomes). Certain types of calcein encapsulating flexible liposomes were chosen for in vitro evaluation of calcein (human) skin permeation, using Franz diffusion cells. In order to understand the relevant implication of elastic vesicle transfer into deeper skin layers, on the vesicle-induced enhancement of calcein permeation, skin penetration experiments were carried out with calcein encapsulating and rhodamine-lipid (RHO-L) incorporating vesicles. In all cases, the amount of calcein and RHO-L in each skin layer was quantified after extraction from the tape-strips and cryotome sections skin layers. Franz cell experiment results reveal that the vesicles enhance calcein permeation in the order INV > TRANS > LIP. The same trend was demonstrated for calcein penetration into deeper skin layers, by SC tape-strip studies after 6h non occlusive application. Finally, by comparing calcein penetration into deeper skin layers with that of RHO-L it is concluded that the penetration of vesicles follows the same order with that of enhanced calcein permeation. It may be thus concluded, that between the vesicle types studied, the Invasomes that seem to move at higher amounts into SC and especially into deeper skin layers, also demonstrate higher enhancement of calcein permeation, when calcein is entrapped into them.