Linear and predictable scale-up in the fixed-bed bioreactor

One of the main advantages of selecting a structured fixed-bed bioreactor is the ability to scale-up in comparison to other culture systems. The scale-X™ bioreactors’ design and performance features allow for linear predictability for process parameter scale-up.

Flatware, static, and certain dynamic systems have no option but to scale-out, and while stirred-tank bioreactors can scale-up, they do not do it linearly (process conditions/parameters must be exponentially considered with volume increase). For example, agitation speed in a stirred-tank bioreactor increases drastically with the volume of the tank, which adds shear to the system, potentially damaging cells. These challenges of nonlinear scalability increase the risk of scale-up failure in stirred-tank bioreactors.

Univercells Technologies’ bioreactor platforms are designed for scalability. The scale-X fixed-bed bioreactor range and the NevoLine™ Upstream platform scale-up linearly (e.g. process conditions or parameters are 3 times greater if the volume is 3 times greater). The fixed bed’s height is kept the same across the different scales with multiple stacked fixed-beds to increase the surface area.

The systems’ design and performance parameters enable flexibility to accommodate a variety of specific process parameters.

Design and performance parameters in the scale-X bioreactor platforms

  • Inoculation strategy (density, flow rate, volume, mode of operation)
  • Recirculation and/or perfusion rates (max and min)
  • kLa (measure of the aeration capacity of a system)
  • Shear (strain on the cells)
  • Impeller speed and linear speed in housing design/ geometric dimensions
  • Volume-to-Surface Ratio
  • Mixing time/volumetric gas flow

For more technical details ask your Univercells Technologies Sales representative or Bioprocess specialist.

These features are conserved streamlined from the scale-X carbo to the nitro bioreactor (integrated in the NevoLine Upstream platform) to ensure a consistent and transitional scale-up across the product line.

The scale-X carbo (10 and 30 m2) and scale-X nitro (200 and 600 m2) bioreactors share many design space features such as circulation, fixed-bed compaction, and overlapping kLa ranges that make process-specific parameters predictable.

The scale-X hydro bioreactor platform is primarily a proof-of-concept and R&D system to advance process knowledge in a similar structured fixed-bed environment as the scale-X carbo and nitro bioreactors.

The challenges of scale-up underlie the capability of the selected cell line and specific product attributes for product quality and productivity, but many other process parameters typically need to be adjusted for optimal conditions.

Process parameters for consideration include (but are not limited to):

  • Seeding density (highly dependent on cell line)
  • Seed train (highly dependent on cell line and process)
  • Media composition/metabolite consumption (highly dependent on cell line)
  • Volumes
  • Durations
  • Pump speeds/flow rates
  • pH, temperature, dissolved oxygen (cell line and/or process dependent)
  • Lysis strategy or product release kinetics (product stability)
  • Final scale

For more technical details ask your Univercells Technologies Sales representative or Bioprocess specialist.

Determining these parameters for a specific process is not always easy. The scale-X bioreactors can help!
The linear scalability minimizes the risk of an unsuccessful scale-up, providing a potential faster time-to-clinic/time-to-market.

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