Measurement of Oxygen Transfer Rate and Specific Oxygen Uptake Rate of h-iPSC Aggregates in Vertical Wheel Bioreactors to Predict Maximum Cell Density Before Oxygen Limitation

This publication combines oxygen-transfer measurements from large Vertical-Wheel bioreactors with specific oxygen-uptake measurements from human induced pluripotent stem cell aggregate cultures. Oxygen mass-transfer coefficients were measured under different agitation rates, working volumes, and headspace gas-flow conditions in 3, 15, and 80 L systems. The specific oxygen-uptake rate of iPSC aggregates was measured in a 0.1 L bioreactor using a custom dissolved oxygen probe configuration. These datasets were combined to estimate theoretical maximum cell densities before oxygen becomes limiting at working volumes ranging from 2 to 80 L. The study provides an engineering method for aligning biological oxygen demand with vessel gas-transfer capacity. The results are intended to guide process design, operating ranges, and scale-up of shear-sensitive aggregate cultures without assuming that conventional aeration approaches are suitable for every cell type.