Abstract
Bioreactors are widely used for the growth and maintenance of tissue-engineered constructs. In this paper, we report on work directed toward a better understanding of the chemical and fluid-mechanical environments that are needed to enhance cell function and tissue growth in bioreactors. We have conducted cell-growth studies in well-controlled flow conditions that indicate the effect of shear stress and oxygen tension on cellular function. In more complicated bioreactors, like the NASA rotating-wall vessel bioreactor, we have done experimental and numerical fluid-mechanical studies that quantify the velocity and shear-rate fields near a three-dimensional construct suspended by the flow inside the bioreactor. All of these results will be used to develop the tools needed to properly design and operate bioreactors for the optimal growth of tissue substitutes.
