In recent years considerable attention has been focused on the development of new controlled release drug delivery systems. Essential to the development of successful controlled delivery systems is the understanding of the interaction of various design parameters, such as geometry and physical properties, with the actual diffusion process. Mathematical modeling, together with numerical simulation, can provide useful guidance and insight to the experimentalist in controlled release, and can greatly reduce the number of experiments needed in o rder to obtain the desired release profiles. Current diffusion based mathematical models are far from attaining this goal in all but the simplest cases.

As a first step towards simulating real life experiments in the realm of controlled drug release the present research has set out to develop and numerically solve a general continuum model which can describe all the physical processes relevant to controlled release systems, such as diffusion, phase change (plasticization), structural deformations, chemical reactions etc., and which is suitable for large scale numerical computations using the Finite Element Method (FEM). Application of such an approach to the drug release problem is novel and promising.

Preliminary results have been obtained for the PerioChip, a commercial biodegradable drug release device. This system was modeled as a reaction diffusion problem and the equations were solved with the FEM code FIDAP. These preliminary results indicate that the quality control experiments performed on the PerioChip drug delivery system can be significantly reduced.