A viscous pump bioreactor.

Area of Science:

• Bioprocess Engineering
• Cell Culture Technology
• Fluid Dynamics

Background:

• Mammalian cell bioprocessing requires specialized bioreactor designs to maintain cell viability.
• Traditional agitators often induce high mechanical stress, damaging fragile anchorage-dependent cells.
• Achieving adequate fluidization and mixing without compromising cell integrity is a significant challenge.

Purpose of the Study:

• To design and characterize a low mechanical stress agitator for large-scale bioprocessing.
• To evaluate the fluid dynamics of a novel rotating disc agitator for mammalian cell culture.
• To ensure efficient mixing and cell fluidization while minimizing hydrodynamic shear stress.

Main Methods:

• Fluid dynamic design of a rotating disc agitator and bioreactor vessel.
• Flow visualization techniques to observe microcarrier behavior.
• Laser Doppler velocimetry (LDV) to quantify fluid velocity and turbulence levels.

Main Results:

• The rotating disc agitator successfully fluidizes microcarriers in large-scale bioreactors.
• Flow visualization and LDV measurements confirm a gentle, three-dimensional flow pattern.
• Low turbulence levels and minimal hydrodynamic shear stress were observed, indicating reduced cell damage potential.

Conclusions:

• The proposed rotating disc agitator is suitable for large-scale bioprocessing of anchorage-dependent mammalian cells.
• This design effectively balances mixing requirements with the need for low mechanical stress.
• The findings suggest a promising approach for improving cell viability and process efficiency in biopharmaceutical manufacturing.