With the widespread application of Tangential Flow Filtration (TFF) and Alternate Tangential Filtration (ATF), the efficiency of the perfusion process has been greatly improved.

Consequently, an increasing number of biopharmaceutical companies have begun to develop and implement the perfusion process.

What is the perfusion process?

Perfusion process refers to continuously perfusing the culture medium (including medium, additives, alkali, etc.) into the fermenter during the biological fermentation process, while simultaneously flowing out waste culture medium (including depleted medium, cell waste, sampling volume, etc.) at the same flow rate, thereby providing a relatively constant culture environment to achieve a higher unit yield.

A stabilized perfusion process requires proper control of the medium replenishment and efflux rate to maintain the desired perfusion rate. Through real-time monitoring of live cell concentration, stabilization of the desired cell-specific perfusion rate (CSPR), and regulation of cell efflux by parameters such as perfusion rate, a constant working volume and cell density can be maintained in the reactor.

Usually, the level of offline control has a significant influence on the performance of the production process and product quality. It was shown that in the production of recombinant human interferon beta (β-IFN) from CHO cells, the low-temperature perfusion culture could increase the yield by 3.5-fold and the yield per unit volume by 7-fold compared with that of batch culture.

Additionally, it could reduce aggregation by 39% and enhance bioactivity to a certain extent.

A brief perfusion in the bioreactor, followed by a traditional recharge batch culture using highly concentrated recharge material, almost doubled the overall yield compared to the conventional recharge batch process.

The integrated system of a perfusion reactor and a four-column periodic countercurrent chromatography was utilized to continuously capture target proteins at significantly higher yields per volume compared to current perfusion or recharge batch cultures.

Fluid control is very important in the perfusion process, and two types of control methods are typically applicated in the process.

One method involves pumping out the spent nutrient solution at a specified rate based on the perfusion rate, while the fresh nutrient solution is automatically replenished through feedback control to maintain a consistent culture volume.

One approach is to replenish the fresh culture solution at a specified rate, while the waste nutrient solution is automatically pumped out based on the level of the culture solution. In the event of a failure of either the discharge pump or the replenishment pump, the former may cause the bioreactor to empty, while the latter may cause the reactor to overflow.

How can we avoid the bad situation mentioned above?

XY-TEK ultrasonic flow sensor can effectively measure the flow rate in the liquid pipelines.

Beside these, the XY-TEK ultrasonic flow sensor offers the following advantages in the biological perfusion process.

1.More Hygienic and Safer

XY-TEK CG series ultrasonic flow sensor adopts clamp-on non-invasive design, it can accurately measure without contaminated the fluid flow. This design helps avoid the risk of cross-contamination, ensuring that the nutrient solution and other liquids remain clean and sanitary.

2. More Accurate and Reliable

XY-TEK CG series ultrasonic flow sensors provide measurement accuracy of up to ±2% or even higher, guaranteeing more precise and reliable measurements.

3. More Compact and Efficient

XY-TEK CG series ultrasonic flow sensors adopt integrated design, with built-in circuits, and processing systems. It can provide international standard communication protocols and various output signals.

This facilitates integration and connection with a variety of control systems and data acquisition equipment, making it convenient for perfusion processes. Through the connection with computers or PLCs and other systems, it can display and record flow data in real-time, generate various visualization charts and reports, and help improve the efficiency of the irrigation process.

4. More Versatile and Widely Applicable

Ultrasonic flow sensors support bidirectional measurement, have a broader measurement range, and are suitable for various fluid characteristics and perfusion conditions. They can accurately measure fluids with low or high viscosity. At the same time, it also has a bubble detection function.

In summary, as the perfusion process becomes more mature and refined, an increasing number of biopharmaceutical companies are choosing perfusion processes.

The XY-TEK ultrasonic flow sensor, is aiding in enhancing the yield per unit volume in the perfusion process. This technology also helps in effectively controlling production costs, making it increasingly popular among biopharmaceutical companies.