Affiliations: Philips Consumer Lifestyle, Drachten, The Netherlands | Eindhoven University of Technology, Eindhoven, The Netherlands | Philips Research, Eindhoven, The Netherlands
Note: [] Address for correspondence: Dr. Cees Oomens, Biomedical Engineering Faculty, Eindhoven University of Technology, P/O Box 513, 5600 MB Eindhoven, The Netherlands. Tel.: +31 40 247 2818; Fax: +31 40 244 7355; E-mail: [email protected].
Abstract: This study presents an in vitro experimental method to determine shear properties of the epidermis. Shear tests were performed with a parallel plate rheometer on samples of stratum corneum and the viable epidermis. The method was validated on very thin silicon sheets. Preliminary test were performed to determine the linear viscoelastic range, the effect of normal loading on the sample and the time to reach equilibrium after changes of temperature and relative humidity. The study shows that reproducible results can be obtained for the shear properties of epidermis in an in vitro set up. The dynamic shear modulus for stratum corneum ranges from about 4–12 kPa, decreasing with increasing relative humidity. The values are considerably lower than the shear modulus value based on tensile Young's moduli in the literature, indicating a considerable anisotropic material behavior. Results for the epidermis were of the same order of magnitude, but were less consistent possibly due to a less well-defined tissue composition.
Keywords: Stratum corneum, epidermis, mechanical properties, in vitro
DOI: 10.3233/BIR-2011-0590
Journal: Biorheology, vol. 48, no. 3-4, pp. 229-245, 2011
