Abstract

In this article a mathematical model is presented in which the fluid dynamic interaction between the liquid flow in a scaffold and growing cells is simulated. The model is based on a computational fluid dynamic (CFD) model for the representation of the fluid dynamic conditions in the scaffold. It includes furthermore a simple biological growth model based on Michaelis Menten type kinetics for the growth of cells. The model includes biomass, substrate and oxygen as the most important growth limiting components in the system. Furthermore the growth, decay and maintenance respiration of the cells are considered in the model. In a variation of the model the growth of the biomass is influenced by the fluid dynamic induced shear stress level, which the cells are exposed to. In parallel an experimental growth of stem cells has been performed in a 3D perfusion reactor system and the culturing has been stopped after 2, 8 and 13 days. The development of the cells is compared to the simulated growth of cells and it is attempted to draw a conclusion about the impact of the shear stress on the cell growth.

Keywords: Computational fluid dynamics (CFD), bioreactor, tissue engineering, scaffold, micro pores, fluid structure interaction, Raimondi, Hyalograft 3D, Michealis Menten kinetic model, shear stimulation model, Michaelis Menten type kinetic model, 3D perfusion bioreactor