Scale Trends Downward
“An interesting trend is that improvements in expression technology are making it more feasible to work with the new disposable technology,” observes Darby.
Needs and capabilities are now converging. Even as the demand for larger-scale disposable options grows, there is an emerging recognition that as gene-expression levels continue to increase, large-scale bioreactors may not be necessary to produce the quantities of biomolecules needed for biotherapeutic and vaccine manufacturing.
In fact, Hodge predicts declining popularity of 10,000–20,000-liter bioreactors, with a shift in scale to 1,000, 2,000, and 5,000 L volumes. Xcellerex recently added a 2,000 L XDR™ bioreactor to its FlexFactory™ biomanufacturing platform. XDR bioreactors are also available in 200, 500, and 1,000 liter working volumes and smaller-volume units are in development. Xcellerex also offers XDM QUAD™ single-use mixing systems.
As cell culture systems are able to generate more product per batch, the requirements for the bioreactor technology become more stringent and include the need for a broader range of sensors and probes, online monitoring, and real-time feedback control capabilities—the types of process controls that are available on traditional stainless steel systems.
Thermo Fisher Scientific’s open-architecture design approach allows customers to select one of the company’s single-use bioreactors (S.U.B.) and couple it to their choice of control systems, probes, and fittings. “Customers seek this flexibility to incorporate new disposable technology such as sensors into their single-use bioreactor without restriction to the manufacturer of the technology,” says Brandon Pence, associate director of market management at Thermo. The HyClone S.U.B. system consists of a reusable stainless steel out support container and a single-use BioProcess Container and is available in 50, 100, 250, and 1,000 L maximum working volumes.
HyClone Single-Use Mixers (S.U.M.) incorporate the same stirred-tank design used in the S.U.B. They range in volume from 10 L to 1,000 L and are suitable for hydration of powdered media, preparation from liquid concentrates, and other liquid applications. The new S.U.M. docking station facilitates storage of materials after mixing while freeing the mixing station to process a new batch. The docking station detaches from the mixing vessel and BioProcess Container.