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Published on: February 9, 2016
Hypothesis: the epidermal permeability barrier is a porous medium
1Dept. of Medicine, University of British Columbia, Vancouver, Canada. nkitson@interchange.ubc.ca
Abstract:
The stratum corneum is a complex biological material characterized by very low permeability to water and most other molecules. This material may be thought of as a 'porous medium' composed of impermeable and permeable regions. Intercellular lipid membranes in the stratum corneum are postulated to exist in a mixture of two phases: solid (i.e. impermeable) and liquid crystalline (permeable). The corneocyte envelope is classified as impermeable. Diffusion mechanisms of solutes within, across and between the intercellular lamellae are discussed. This model represents a refinement of previous theories about the physical structures responsible for the low observed permeability of the stratum corneum.
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