Iontophoretic transdermal drug delivery: a multi-layered approach
  We present a multi-layer mathematical model to describe the the transdermal drug release from an iontophoretic system. The Nernst-Planck equation describe the basic convection-diffusion process, with the electric potential obtained by Laplace equation. These equations are complemented with suitable interface and boundary conditions in a multi-domain. The stability of the mathematical problem is discussed in different scenarios and a finite-difference method is used to solve the coupled system. Numerical experiments are included to illustrate the drug dynamics under different conditions. 
Giuseppe Pontrelli, Marco Lauricella, Jose' A. Ferreira, Goncalo Pena
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