A two-layer model for drug delivery from a transdermal patch
A two-phasemathematical model describing the dynamics of a substance between two coupled media of different properties and dimensions is presented. A system of partial differential equations describes the diffusion
and the binding/unbinding processes in both layers. Additional flux continuity at the interface and
clearance conditions into systemic circulation are imposed. An eigenvalue problem with discontinuous
coefficients is solved and an analytical solution is given in the form of an infinite series expansion.






