Modelling the Oxygen Distribution in a Perfused Bioreactor for Cartilage Production

Introduction. We describe a continuous modelling and simulation framework aimed at monitoring and steering a recently developed bioreactor for cartilage production based on mesenchymal stem cells (MSCs). This bioreactor provides online-access to the cell density by acoustic measuring sections. An appropriate oxygen distribution throughout the bioreactor is essential for a successful expansion and chondrogenic differentiation of the cells. We use experimentally validated knowledge on the oxygen dependence of MSC organisation in order to simulate this distribution. The aim of the present study is to verify in a spatially two-dimensional setting that our modelling framework is suitable for monitoring the relevant processes in the bioreactor and consequently can serve as a sound basis for threedimensional models for bioreactor control.