Mechanical Properties of the Human Stratum Corneum: Hydration Effects on Graded Delamination of Human Stratum Corneum

Reinhold Dauskardt Stanford University, Professor Materials Sciences and Engineering The stratum corneum (SC) is the outermost layer of the skin. Its process of reneweal is regulated by various mechanisms, including chemical and structural gradients through the SC thickness. In this study, an in vitro mechanics approach for studying the delamination behavior of SC in the direction perpendicular to the skin surface is applied to study the through-thickness mechanical properties of human SC. The effects of elevated tissue hydration are examined through tests performed on specimens either equilibrated and tested at high hydration or placed in a high relative humidity environment. Initial delamination values for both are lower than for an untreated control, while the delamination energies of subsequent SC layers are in fact higher than for the untreated control.