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How much media to add to a flask for cell culture?


How much media to add to a flask for cell culture ?
RADOBIO sterile cell culture Erlenmeyer flasks are specifically designed for cultivating suspension cells including HEK 293 and CHO cells. These flasks feature a ​​flat bottom​​ and a ​​vented cap​​, making them suitable for small-scale process development, scale-up, and multi-stage cultivation. The vented cap integrates a ​​0.2 μm hydrophobic membrane​​, which enables efficient gas exchange while blocking microbial contamination and water penetration, ensuring optimal cell growth conditions
 

Key Specifications and Usage Guidelines​​

  1. 1.​​Working Volume Optimization​​
    •      •Medium volume should be maintained at ​​20–30%​​ of the total flask capacity to ensure adequate oxygen transfer and minimize shear stress
       
    •      •Clear graduation marks on the flask allow precise volume measurement
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  2. 2.​​Shaking Parameters​​
    •      •Recommended incubator shaker shaking speed: ​​75–120 RPM​​ (adjustable based on experimental needs)
       
    •      •For larger flasks (≥3L), reduce speed to ​​90 RPM​​ to prevent excessive fluid shear and foaming

​​Recommended Parameters for CHO & HEK 293 Cells​​

Flask Volume Working Volume Shaking Speed
125 mL 25 mL 120 RPM
250 mL 60 mL 120 RPM
500 mL 150 mL 120 RPM
1000 mL 350 mL 120 RPM
1500 mL 400 mL 120 RPM
2000 mL 400 mL 120 RPM
3000 mL 800 mL 90 RPM
5000 mL 2500 mL 90 RPM

Note: Data applies to CHO Stable, CHO Transient, and HEK 293 Transient cell lines


​​Supplementary Technical Details​​

  1. 1.​​Material and Sterility​​
    •      •PETG/PC Material Options​​:PETG offers high transparency and impact resistance; PC provides superior thermal stability (withstands autoclaving at 121°C)
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    •      •​​Sterilization​​: Gamma-irradiated, individually packaged, certified ​​DNase/RNase-free, endotoxin-free​​, and compliant with ​​USP Class VI​​ standards
       
  2. 2.​​Design Advantages​​
    •      •​​Ergonomic Cap​​: Facilitates secure handling and compatibility with pipettes/cell scrapers
       
    •      •​​Baffled Models Available​​: Enhances mixing efficiency for high-density cultures by increasing oxygen transfer (kLa)
       
  3. 3.​​Critical Usage Notes​​
    •      •​​Avoid Overfilling​​: Volumes >30% may reduce gas exchange, leading to hypoxia in aerobic cultures
       
    •      •​​Monitor pH/Oxygen​​: Maintain pH at ​​7.0–7.4​​ (CHO cells) and dissolved oxygen (DO) >40% for optimal metabolism
       
    •      •​​Shear Sensitivity​​: For shear-sensitive cells (e.g., primary T cells), use lower speeds (80–100 RPM) or anti-foam agents

​​Applications Beyond Standard Cultivation​​

  •      •​​Perfusion Systems​​: Integrate with feed lines for continuous nutrient supply, achieving cell densities >20 × 10⁶ cells/mL
     
  •      •​​Microbial Cultures​​: Suitable for bacterial/yeast fermentation with baffled designs for improved aeration
     
  •      •​​Scale-Up Protocols​​: When transitioning from flasks to bioreactors, maintain consistent ​​volumetric oxygen transfer rate (kLa)​​ by adjusting agitation and aeration
     

Post time: Aug-17-2025