A Model of Solute Transport through Stratum Corneum Using Solute Capture and Release

Abstract

A one-dimensional model of solute transport through the stratum corneum is presented. Solute is assumed to diffuse through lipid bi-layers surrounding impermeable corneocytes. Transverse diffusion (perpendicular to the skin surface) through lipids separating adjacent corneocytes, is modeled in the usual way. Longitudinal diffusion (parallel to the skin surface) through lipids between corneocyte layers, is modeled as temporary trapping of solute, with subsequent release in the transverse direction. This leads to a linear equation for one-dimensional transport in the transverse direction. The model involves an arbitrary function whose precise form is uncertain. For a specific choice of this function, closed form expressions for the Laplace transform of solute out-flux at the inner boundary, and for the time lag are obtained in the case that a constant solute concentration is maintained at the outer skin surface, with the inner boundary of the stratum corneum kept at zero concentration, and with the stratum corneum initially free of solute.

Light–Tissue Interaction at Optical Clearing

“…The SC is between 100 and 200 mm thick. Appendages such as hair follicles and sweat glands cover approximately 0.1% of the total skin surface [70]. Polar structures such as corneodesmosomes contribute to SC cohesion [6].…”

“…Thus, the heterogeneous nature of SC provides some possible pathways for solute transport: appendageal, transcellular (through both corneocytes and lipid bridges), and intercellular (through the lipid phase only) [70]. Lipophilic and polar permeants are transported by the lipoidal and pore pathway of SC, respectively [71].…”

A novel approach to modelling water transport and drug diffusion through the stratum corneum

“…The authors would like to thank Bob Russell and David Muraki for valuable comments. Also, the authors would like to thank the anonymous reviewers for their valuable comments, including the suggestion to incorporate references [5-11] and [27] in the text, unknown to us when this manuscript and reference [13] were written. At the time when research was performed, TML was supported by CONACyT (Mexico, Consejo Nacional de Ciencia y Tecnología, grant number 148724).…”

“…Namely, the SC is composed of stacked, polyhedral corneocytes surrounded by lipid membranes and, for the sake of simplicity, can be thought of as a brick wall composed of dead cells (the "bricks") and intercellular lamellar membranes (the "mortar"), as depicted in Figure 2. Such geometry has been previously considered in simplified one-dimensional [5] or two-dimensional diffusion models [6-8], and within studies linking permeability and solubility [6], SC geometry and permeability [9], and the dependence of diffusivity and general SC barrier properties on permeability, corneocyte alignment and lipid content [6,9-11]. …”

Mathematical model formulation and validation of water and solute transport in whole hamster pancreatic islets

“…This approach has been used in other tissue types in various ways. For example Mollee and Bracken describe a model that encompasses cell-to-cell transport along with transverse diffusion in the Stratum Corneum [20]. Their model uses a particular “solute capture and release” function to model the transverse diffusion through the lipids contained between corneocyte layers.…”