During the past decade, single-use bioreactors have become widely accepted and often preferred in development and manufacturing processes. In particular, single-use vessels have proven perfectly suitable for the cultivation of low-oxygen-demanding cell types such as mammalian and insect cells.
These bioreactors can offer significant advantages over their reusable glass and stainless steel counterparts, including labor and cost savings, rapid turnaround between runs, and flexibility. This article focuses on single-use bioreactor design advancements introduced in the new benchtop CelliGen® BLU stirred-tank bioreactor (Figure) from New Brunswick Scientific.
Control of pH and dissolved oxygen (DO) is critical in cell culture; use of traditional pH and DO probes, however, requires significant time and can introduce contaminants. The CelliGen BLU system features a novel noninvasive pH and DO port and sleeve design, enabling accurate readings without either probe coming in direct contact with the culture.
The DO sleeve allows gas to readily diffuse across a permeable membrane into the sleeve where it is sensed by the probe. This design has several advantages over the current methodology. It eliminates contamination risks, as there is no contact between the vessel interior and the DO sleeve space where the probe is inserted. Vessel setup time is reduced because the reusable DO probe does not have to be sterilized and re-polarized for each run—a procedure that ordinarily takes about 6–8 hours. It also allows a nonsterile probe to be used, as the sleeve is a barrier to any contaminants, eliminating autoclaving and thereby extending probe life.
The CelliGen BLU also uses a noninvasive, optical pH probe that doesn’t need to be autoclaved (it is not a traditional gel-filled pH probe).