reported that liposomes up to 600 nm in diameter penetrate through skin rather easily, whereas liposomes with 1,000 nm and more remain interiorized in the stratum corneum. Although the stratum corneum is widely recognized as the main barrier to percutaneous absorption, it is also considered as the main route for penetration. However, recent reports have suggested that, besides the transepidermal route, hair follicles and sebaceous glands may significantly contribute to transdermal delivery.