Computational Assessment of Oxygen Availability and Shear Stress in Microfluidic Cell Culture Chambers for Optimized Cell Adhesion.

Microfluidic cell culture systems provide controlled microscale environments for biomedical research; however, cell viability within closed microchambers depends on adequate oxygen availability during the adhesion phase and on the mechanical stresses generated after perfusion begins. Experimental characterization of oxygen depletion and local shear stress remains challenging due to the small dimensions involved and the complexity of transport phenomena. In this study, a computational framework was developed to assess oxygen transport and hydrodynamic shear stress in an SU-8-based microfluidic culture chamber. Oxygen diffusion and cellular consumption were first modeled under static conditions to determine cell survival time prior to perfusion. The influence of chamber height on oxygen availability was investigated, and an empirical correlation was derived to predict oxygen concentration as a function of chamber geometry. Subsequently, medium perfusion was introduced, and the resulting wall shear stresses acting on adhered cells were evaluated under different flow conditions. The simulations demonstrated that chamber height significantly affects oxygen depletion time, while both chamber geometry and flow rate influence the magnitude of wall shear stress. The proposed framework provides practical design guidelines for optimizing microfluidic culture systems, enabling adequate oxygen supply and physiologically compatible mechanical conditions while reducing reliance on extensive experimental testing.