Characterization of Penetration of Particles After Dermal Application

The effect of cosmetic formulations containing nanostructures should stabilize the actives, enhance their penetration efficiency or provide a reservoir for the actives. Exceptions are nanostructures in sunscreens and make-ups with glitter effects. They should not penetrate in the viable epidermis. Methods to investigate these promises should provide a depth resolution and, if possible, should be non-destructive. In this chapter, different methods are presented to monitor stratum corneum, hair follicle and transdermal penetration of the actives and/or nanostructures.