Contact and frictional properties of stratum corneum of human skin

摘要

Most skin tribology studies gave attention on the examination of frictional properties of normal and healthy skin surfaces. This study aims to investigate the frictional and mechanical properties of skin under different load and friction conditions after removing the stratum corneum from the designated uninjured forearm tissue by a tape stripping method. The influence of water on friction coefficient was explained by using adhesion model of friction. For quantifying the amount of removed stratum corneum from the skin surfaces, an UV/vis spectrum analysis was used to measure the absorbance and pseudo-absorbance of stratum corneum on the tape. To evaluate the influence of water on friction coefficient, trans-epidermal water loss (TEWL) value of different skin conditions was assessed by water evaporation measurements. Frictional and mechanical properties of the skin surfaces were acquired via a tribometer. Results revealed that the elastic modulus of skin decreased and the friction coefficient of skin increased with the increasing of the amount of removed stratum corneum. Friction force versus normal force was presented to explain the influence of water on friction coefficient and section change phenomenon of friction coefficient under different degrees of tape strips.