What are the main scale-up strategies for bioreactors?

Scale-up strategies aim to maintain critical parameters from bench to production scale. Common approaches: constant kLa (maintains oxygen transfer, most common for aerobic processes), constant power per unit volume (P/V, maintains mixing intensity), constant impeller tip speed (limits shear stress for sensitive cells), constant mixing time (ensures homogeneity), and constant Reynolds number (maintains flow regime). No single criterion works for all processes - selection depends on critical process parameters. Typically, maintaining kLa is prioritized for aerobic processes, while shear-sensitive mammalian cells may prioritize tip speed limits. Computational fluid dynamics (CFD) increasingly aids scale-up predictions.