Biostat® RM TX & Flexsafe® RM TX Bags

The Ideal Combination for Your Cells 

The Biostat® RM TX system consists of an automated control unit and a rocking platform, for gently agitating a single-use Flexsafe® RM bag. Enabling the ex vivo expansion of patient-specific T cells or other types of immune cells, the Biostat® RM TX is suitable for process development, as well as for the expansion of relevant cell numbers. Fed-batch, perfusion processes or a combination of culture modes are all possible with this system.


Regenerative Medicine

Regenerative Medicine therapeutics repair, replace and engineer human cells, tissues and organs to restore their normal function. The discipline has great potential to address clinical needs that are currently unmet by conventional pharma or biopharmaceutical products. Rocking motion bioreactors are widely used for the expansion step during stem and T-cell cultivation processes, incl. CAR-T. Companies are actively approaching us to work on the integration of our rocking motion bioreactors into their process environment and explore the PAT capabilities coming with our single-use systems. Tests that these customers perform with Flexsafe® RM bags continue to be successful, even for the most sensitive cells.   

The Right Solution for Your Needs

At Sartorius, we help you develop a scalable, cost-effective process and combine this with the security of our worldwide supply chain and manufacturing capabilities. Our expertise and experience allow us to support early stage process development and establish scalable processes.

The complete control of our raw materials, the extrusion process and the bag assembly, provides lot-to-lot product consistency.

In collaboration with our resin and film suppliers, we have optimized the resin and minimized the additives in our Flexsafe® film technology ensuring excellent, reproducible batch-to-batch culture performance of even the most sensitive cells.

Learn More about Flexsafe® Technology

  • A fixed perfusion membrane* (PES, 1.2 μm) forms a compartment for removal of cell free media during the perfusion process, providing minimal loss or damage to the cells
  • Single use sensors for pH, DO and viable biomass enable sophisticated process control with reduced sampling need
  • 100% integrity tested, gamma-irradiatable and fully validated Sartopore® Air sterile filters continuously protect the culture from contamination
  • Industry standard tubing option (DEHP free PVC) for seamless connection to up- & downstream processes

* Perfusion bag design protected by patents US 9 017 997 B2 and EP 2 268 788 B1

Conventional harvesting procedures can reduce the number of live cells and affect cell viability. Since cell yield is critical for autologous cell therapies, we have designed our Flexsafe® RM TX bags with a special port for hands-free gravity harvesting. This unique gravity harvesting concept in combination with the Flexsafe® RM TX Harvest Device allows the safe recovery of as many cells as possible by reducing shear stress on these delicate cells and minimizes contamination risks from manual handling.

Our Biostat® B control unit is ideal for walk-away automated analysis and control of perfusion cultures.

Benefit from:

  • Advanced control and monitoring of gas mixture and flow rate, filling volume and substrate addition; parallel activation of multiple controllers provides maximum flexibility
  • On-line viable biomass analysis with culture volumes greater than 500 mL
  • Up to 4 internal pumps can be integrated into control loops for ease of operation without the need to constantly change the pump's function.
  • Easy connection to industry standard Distributed Control (DCS) or Supervisory Control and Data Acquisition (SCADA) systems such as BioPAT® MFCS, Siemens PCS 7 or Emerson DeltaV™. Straightforward integration into existing automation and single-use infrastructure for data and process consistency throughout
  • Complete qualification of the system for GMP use to support regulatory compliance

Discover the Biostat® RM TX


CountryPatent number


US 6,673,532 B2

US 7,041,493 B2

US 8,304,231 B2

US 6,673,532 B2

US 9,017,997 B2 


EP 1 309 719 B1

EP 1 778 828 B1

EP 2 268 788 B1

EP 2 945 978 B1

EP 2 945 801 B1








Biostat® RM TX with Flexsafe® RM TX

PDF | 6.4 MB

Flexsafe® RM Disposable Cultivation Chambers for Rocking Motion Bioreactors

PDF | 927.2 KB

BIOSTAT® RM Selected Bibliography

PDF | 1.4 MB

Consult Our Experts

Consult Our Experts

Disclaimer: BIOSTAT ® RM TX and Flexsafe® RM TX bags are for research use or further manufacturing use only – not for use in therapeutic or diagnostic procedures. They are not CE marked for in vitro diagnostic use nor are they medical devices. Drug manufacturers and clinicians are responsible for obtaining the appropriate IND | BLA | NDA approvals for clinical applications.

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