Math Biology Seminar Abstracts

Monday October 27, 2003

Modeling of Rhythmic Drug and Hormone Delivery

Ronald Siegel

Department of Pharmaceutics, University of Minnesota

Abstract: In order to meet the need for an implantable hormone delivery system that releases gonadotropin releasing hormone (GnRH) in rhythmic pulses, we have constructed a hydrogel/enzyme system whose swelling, and hence permeability to GnRH, oscillates autonomously when fueled by constant levels of glucose. The system exhibits limit cycle-type behavior, due to an unstable negative feedback between an enzyme reaction, and a hysteretic phase transition exhibited by the hydrogel. We will present a lumped model of this system, which reproduces some of the observed behaviors. In addition, we will discuss a preliminary model for the optimization of drug delivery for drugs that exhibit tolerance.

For more information contact J. Keener, 1-6089

E-mail: keener@math.utah.edu