Drug delivery in biological tissues : a two-layer reaction-diffusion-convection model

In this paper we present a general model of drug release from a drug delivery device and the subsequent drug transport in biological tissue. In order to study the complete process, a two-phase mathematical model describing the transport of a drug between two coupled media of different properties and dimensions is presented. A system of partial differential equations describes both the solid-liquid transfer and diffusion processes in the polymeric substrate as well as diffusion, convection and reaction in the tissue layer. The model serves as a useful tool for providing insight into the concurrent effects of the diffusion, convection, solid-liquid transfer and reaction parameters in drug delivery systems