Evaluating of Stericup^® Quick Release Filtration Devices for Fetal Bovine Serum (FBS) in Cell Culture

In this Article: 

• Can You Sterile Filter Fetal Bovine Serum (FBS)?
• Materials and Methods
• Fetal Bovine Serum Filtration Results
• Conclusion

Can You Sterile Filter Fetal Bovine Serum (FBS)? 

Effective filtration helps researchers maintain the purity of fetal bovine serum (FBS) in their cell culture experiments – in these experiments, the FBS must sterile, reliable, and free of contaminants. One way to ensure this is to filter the FBS, but this can be difficult as it can clog sterile filters. Stericup^® filtration devices can be used to streamline the FBS filtration process, maintain sample quality, and ensure cell culture integrity.

Here we evaluate the performance of Stericup^® filtration devices in achieving reliable and efficient serum filtration when compared to other brands. The study includes flow tests on undiluted FBS samples to assess filtration times and throughput as well as practical recommendations and guidelines for optimizing the filtration process.

Overall, we highlight the advantages of Stericup^® Quick Release vacuum filtration devices in serum filtration protocols, emphasizing their usability, ergonomic design, and reliable performance. Detailed flow test data and analysis are presented to help users evaluate the suitability of Stericup^® filters for serum filtration. 

Materials and Methods

• Stericup^® Quick Release (S2GPU05RE)
• 100% Serum - US Origin, EmbryoMax^® ES Cell Qualified FBS, sterile-filtered, suitable for stem cell culture, 500 mL (ES009-M)
• Vacuum/Pressure pump (WP6111560), set to 0.76 bar (22.5”Hg)
• Vacuum line protection:  Millex^®-FG, 0.20 µm, hydrophobic PTFE, 50 mm (SLFG050)
• Silicone rubber tubing, 3/16 in. (4.8 mm) ID, with adapter (XX7100004)
• 0.22 or 0.20 µm polyethersulfone (PES) vacuum filter units, n = 3

Brand	Collection Bottle size (mL)	Membrane shape	Membrane Area (cm2)
PF	1000	Square	69.0
CS	500	Square	33.2
NS	500	Round, 75 mm	44.2
Stericup® Quick Release	500	Round, 73 mm	40.0

Filtering Fetal Bovine Serum Protocol 

1. Using the Stericup^® Quick Release Filtration System, filter 500 mL Fetal Bovine Serum into sterile, PES vacuum filter cup in replicates of 3.
2. Record the processing time.
3. Calculate throughput based on flow rate and membrane area (mL/min/cm²).

FETAL BOVINE SERUM FILTRATION RESULTS 

Four brands of filtration devices, Brand PF, Brand CS, Brand NS, and Stericup^® Quick Release, were tested to determine the usability and performance when filtering FBS for cell culture applications. Regardless of the brand type, there was a consistent filter processing time of less than 2 minutes for the fixed volume of fetal bovine serum (Figure 1). 

Figure 1. Flow time comparison for the sterile filtration of FBS. Brand CS had the longest flow time of 112.1 seconds, followed by Brand NS (74.5sec), then Stericup^® Quick Release (64.2sec), and Brand PF with the shortest flow time of 59.3sec.

However, when this data is converted into flow rates and throughput per surface area (rate/cm² area), it becomes evident that certain brands offer distinct design advantages. The flow rate ranged from 269 mL/min for Brand CS to 506 mL/min for Brand PF (Figure 2). Stericup^® Quick Release demonstrated the highest throughput (~0.2 mL/min/cm²), outperforming the others by 22-37% (Figure 3), while Brand PF exhibited the lowest throughput.

Figure 2. Flow rate comparison for the sterile filtration of FBS. Brand CS had the shortest flow rate at 4.49mL/sec, followed by Brand NS (6.72mL/sec), Stericup^® Quick Release (7.80mL/sec), and Brand PF with the highest flow rate at 8.44mL/sec.

Figure 3. FBS throughput comparison after sterile filtration. Stericup^® Quick Release Filtration systems had the highest throughput at 0.195 mL/min/cm2, followed by Brand NS (0.152 mL/min/cm2), Brand CS (0.135 mL/min/cm2) and Brand PF had the lowest throughput at 0.122 mL/min/cm2.

Conclusion

Here we emphasize the significance of FBS filtration in cell culture and highlight the effectiveness of Stericup^® filtration devices compared to other brands by conducting flow tests on undiluted FBS samples to assess filtration times and throughput. While our results show that all brands achieved similar processing times (less than 2 minutes), the Stericup^® Quick Release demonstrated the highest throughput, surpassing other brands by 22-37%.

Our practical recommendations and guidelines for optimizing the filtration process emphasize the advantages of using Stericup^® Quick Release filters in serum filtration protocols, including their reliable performance.