Exercising greater process control and delivering improved yields are constant challenges for bioprocessing operations. Here’s how mass flow controllers help.
Joe Sipka, Brooks InstrumentThe mass flow controller (MFC) is commonly used in many bioprocessing systems to manage the flow of different gases into bioreactor chambers. Intelligent MFC technology with digital-based flow-control capabilities can help deliver more precise and versatile gas flow control, more sophisticated analysis and resolution of process issues, and can also help equip bioprocess scientists and engineers with data that could lead to improved bioreactor performance.
Role of MFCs in bioreactors
MFCs play an essential role in maintaining a bioreactor’s controlled environment and achieving optimal cell growth. Two critical factors that govern cell culture yield are the levels of dissolved oxygen (DO) in the bioreactor and the pH of the fermentation broth.
Tight control of dissolved oxygen is achieved by using the MFC to enrich the airflow with oxygen, or by depleting it with nitrogen. In turn, maintaining the proper levels of DO regulates cell growth and reduces the production of toxic cell by-products.
Tight control of pH with carbon dioxide flow is also critical. Some bioreactor processes introduce acids and bases to achieve the desired pH level, but this approach is often too harsh for the delicate mammalian cells involved in bioprocessing. Using carbon dioxide (CO2) to tightly control pH levels has been found to be a more effective approach.