Modeling transdermal delivery by electroporation: The thermodynamic approach

Abstract

Low voltage long pulse electroporation of the skin results in localized regions within the stratum corneum of high permeability to mass transfer and electrical conduction. It is believed that these permeability increases result from resistive Joule heating that causes lipid phase changes. This chapter considers the physiology of the stratum corneum and the thermodynamic behavior of the lipid microstructure. A conceptual model of the evolution of the local transport region is presented in order to clearly illustrate the physics underlying this dynamic process. The mathematical equations which govern the conservation of charge, the conservation of thermal energy, and the conservation of drug mass are directly linked to the thermodynamics state of the stratum corneum lipids. The chapter concludes with general modeling considerations to capture increased mass transport associated with electroporation of the skin.