The first batch of cell culture in the new year is handed over to the XDR bioreactor to complete it! The warm-up exercise of cell culture is done~ details make a difference! Preparations before formal large-scale cell culture are important. 2019 New Year is coming, is the circuit of everyone's factory ready for long-term operation and continuous power? If everything is ready, then let's start the cell culture journey of the XDR bioreactor! Why choose an XDR bioreactor? The reason for the similarity in tank design provides a good basis for amplification The XDR 10-2000 L-Series bioreactor has a consistent high aspect ratio (Figure 1), the same type and gradient-amplified impeller diameter, a range of impeller diameter to tank diameter ratio, 4.5 L – 2000 L volume of cells The culture provides a geometrically similar linear Scale-Up and Scale-Down basis. Figure 1 Schematic diagram of XDR 10-2000 L bioreactor The reason is that the minimum culture volume of the XDR reactor is small, flexible and convenient, and the degree of freedom is higher. The bottom agitation design (Figure 2) allows the minimum working volume of the XDR 200 to XDR 2000 to be only 20% of the nominal tank volume. In other words, the 500L XDR reactor can be cell cultured with only 100L of medium and seeds. At the same time, the XDR tank seamlessly expands the working volume, making the N-1, production batch can be easily realized in the same cell culture bag. In the New Year, you can save a consumable fee. Is there a feeling of receiving a red envelope? Figure 2 XDR 10-2000 L bioreactor bottom agitation display Reasons Sancha provides up to five venting apertures to enrich process diversity A good way to ventilate is to be efficient and gentle. The XDR reactor combines aeration and agitation well in the aeration setting. The design of the eight-way gas outlet on the ventilating disc is located below the stirring blade, which enables the stirring blade to uniformly distribute the gas evenly throughout the tank, achieving efficient and gentle ventilation. At the same time, the bottom gas distribution plate can be flexibly selected. The venting aperture includes five sizes of 2 μm, 20 μm, 0.5 mm, 1.0 mm and 2.0 mm T sparge (Fig. 3), which can meet different processes and different usage habits. Figure 3 Design of the gas distribution plate at the bottom of the XDR bioreactor Reasons for four GE ventilation strategies, multiple considerations based on DO, pH and CO2 partial pressure In common experimental production, we recommend using 20 μm or 2 μm bottom pass O2 to control DO. At this time, the maximum oxygen ventilation is small, and it will not cause large shear damage to the cells. CO2 for pH maintenance is also recommended to reduce CO2 total aeration using 20 μm or 2 μm. In order to maintain the CO2 partial pressure in the XDR tank in a lower range, such as controlling the CO2 partial pressure to less than 120 mmHg [1], the easiest way is to drive the CO2 partial pressure by using 0.5-2.0 mm bottom air. In addition to the common bottom gas supply mode of large bubbles plus microbubbles, there are also small partners who prefer to use individual microbubbles or separate large bubbles for gas control. Assuming that the microbubbles are used separately for the bottom gas supply, we can also increase the range of stirring speed in the later stage of the culture to reduce the partial pressure of CO2. Of course, whether the cells can withstand the shear damage of the whole microbubbles is also very important consideration. factor. Assuming the use of large bubbles for bottom gas supply alone, it is necessary to strictly monitor the bag pressure, and at the same time fully prepare the process gas such as Air, CO2, O2, and the backup exhaust gas filter to prevent "chicken flying eggs". Finally put a Rentschler XDR zoom result (Figure 4) town demon, I wish you all the best in the new year, each batch has good results! Promotion and salary increase to achieve the peak of life! Figure 4 Rentschler uses the XDR 200, XDR 1000 scale test process, 12 days CHO DG44 in the XDR bioreactor culture process P / V maintained at 10-23 W · m-3, DO = 50%, pH = 7.0, 36.8 ° C, Day 12 XDR Compared with 7.5% CO2, the cell density of 125 ml shake flask in 306.8 °C culture environment increased by 30%, and cell viability increased by about 15% [2]. references Tetanus Vaccine,Hepatitis B Vaccine For Adults,Tetanus Booster,Td Vaccine FOSHAN PHARMA CO., LTD. , https://www.fospharma.com
1) Cultivate environmental inspection and documentation
2) XDR reactor status, and inspection and preparation of supporting facilities such as TCU, mixing tank, and sterilizer status
3) Preparation of seed cells, culture solution, and feeding
4) Air compressor or air, oxygen, carbon dioxide cylinder preparation
5) Preparation of consumables such as culture bags, electrode sleeves, and piping
6) DO, whether there is a gasket on the pH electrode, DO electrode film integrity, electrode liquid update preparation
friendly reminder: 
1. Hu, WS et al, (2012) "Cell Culture Bioprocess Engineering" Chapter: Scaling up and Scaling Down for Cell Culture Bioreactors.
2. Benjamin Minow. et al, (2013) Fast Track API manufacturing from shake flask to production scale using a 1,000 L single use facility.