Flow, suspension, and mixing dynamics in DASGIP bioreactors: Part 1

Abstract

The bioreactor flow environment has a significant impact on process performance, especially in stem cell cultures. The work of Correia et al found intermittent agitation modes to improve induced pluripotent stem cell (iPSC)-cardiomyocyte differentiation yields; however, to date, the impact within the flow has not been fully characterized. This work aims to characterize the flow dynamics occurring within a commercially available DASGIP bioreactor, equipped with a two-blade paddle impeller, operating under different agitation modes and for two bottom geometries. The paddle impeller configuration generated an axial flow profile due to a large impeller D/T and blade confinement with the bioreactor wall. The application of intermittent agitation was shown to induce two transient spikes in flow velocity and shear stress, the amplification of which increased with dwell duration. Marginally increasing the dwell duration was shown previously to increase differentiation yields, therefore it can be stipulated that introduction of these spikes was favorable toward cardiogenic differentiation.

Chirality enhanced shear‐free mixing of highly viscous fluids in an origami reactor

“…Mixing is an essential unit operation in producing chemicals, 1 food, 2 and pharmaceuticals 3 . The mixing objects include not only conventional gases, liquids, 4 and solid chemical reactants 5 but also various shear‐sensitive substances, such as bacteria, 6 cells, 7 and proteins 8 . Mixing by spontaneous diffusion of molecules is a slower process.…”