Shaking hydrodynamics of flask-based CHO cell cultures evaluated by combining computational fluid dynamics with culture profiling

• Published in: Biotechnology and bioprocess engineering Vol. 30; no. 4; pp. 759 - 775
• Main Authors: Kim, Young Jin, Ryu, Soo Hyun, Lee, Janghan, Kim, Min Hyeong, Lee, Jae Cheol, Park, Chun-Woong, Hong, Jong Kwang
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Society for Biotechnology and Bioengineering 01.08.2025; Springer Nature B.V
• Subjects: Agitation; Biological products; Biopharmaceuticals; Biotechnology; Boundary conditions; Cell culture; Cell growth; Chemistry; Chemistry and Materials Science; Computational fluid dynamics; Computer applications; Data collection; Developmental stages; Digital twins; Energy dissipation; Flasks; Fluid dynamics; Fluid mechanics; Geometry; Humidity; Hydrodynamics; Industrial and Production Engineering; Kinematics; Optimization; Oxygen transfer; Performance evaluation; Research Paper; Shaking; Shear stress; Simulation; Software; Turbulence models; Vessels; Viscosity; United States > US; Agitation speed; Shaking flask hydrodynamics; Computational fluid dynamics; Cell culture optimization; Bioprocess digital twin
• ISSN: 1226-8372; 1976-3816
• DOI: 10.1007/s12257-025-00198-7

Early-stage process development for biopharmaceutical production, including cell line screening and media optimization, is often conducted in shaking flasks, allowing for high-throughput experiments at a relatively low cost. With the increasing diversity of biopharmaceutical modalities, various types and sizes of flasks have been introduced in bioprocess development. However, the determination of optimal operating conditions for these flasks still largely relies on empirical approaches, resulting in uncertainty regarding their suitability. To address this, the study evaluated cell culture performance in three different flask sizes under various agitation conditions, ranging from 20 to 260 rpm in 30 rpm increments. Computational fluid dynamics (CFD) was also employed to analyze the hydrodynamic characteristics at each condition, with a focus on key CFD parameters, including energy dissipation rate, velocity, and shear stress. The results demonstrated that cell growth and antibody production are highly sensitive to both flask shape and agitation speed. Narrow, tall vessels, such as tube spins, required higher agitation (170–230 rpm) for efficient mixing and oxygen transfer, whereas wider, shallower vessels, like Erlenmeyer flasks (EFs), performed well at lower agitation, as low as 80 rpm. CFD analysis highlighted that the broader liquid–air interface in EFs facilitated more efficient oxygen transfer and reduced energy demands. Integrating experimental cell culture data with computational fluid dynamics (CFD) provides a robust framework for optimizing small-scale cultures, laying the foundation for developing bioprocess digital twin models that combine physical and biological data.