Single-Use Assemblies in Bioprocessing: Design and Applications

Single-use assemblies are widely used in biopharmaceutical processes as an independent fluid transfer unit. Cobetter Lifecube™ single-use assemblies offers high flexibility and diverse configurations, enabling a variety of applications in bioprocessing - including upstream bioprocessing cell culture, downstream chromatography purification and formulation filling. We also provide full customized services tailored to different process requirements. 

What Are Single-use Assemblies in Bioprocessing?

Single-use assemblies are custom pre-assembled, single-use solutions designed for fluid transfer in bioprocessing. They usually include tubings, connectors, bottles, filters, bags ,etc. 

Instead of stainless-steel tanks and pipes that need cleaning and sterilizing, these assemblies are pre-sterilized and ready to use. Once the process is done, the whole assembly is thrown away.

Benefits of Single-use Assemblies in Bioprocessing

• Time Saving - No need to clean or sterilize equipment between batches
• Low risk of cross-contamination - Each assembly is pre-sterilized and used only once, so there's no carryover from previous runs.
• Flexibility - Easy to switch products or adjust process steps without dealing with large, fixed systems.

Overall, single-use assemblies help make bioprocessing simpler, faster, and easier to manage—especially in small to mid-scale operations.

Applications of Single-Use Assemblies in Upstream Bioprocessing and Downstream Bioprocessing

1. Cell Culture

Periodic aseptic supplementation and sampling during cell culture are required to monitor and regulate the cultivation, aiming to achieve optimal results. Sterility is one of the critical requirements in bioprocesses. When designing aseptic sampling and connection solutions, contamination risks should be avoided in advance.

The Cobetter Lifecube single-use tubing assemblies include a variety of tubing, connectors, sample bags, and bioprocess containers. These components can be tailored to provide convenient, safe, and rational tubing assembly solutions based on the user's specific process requirements.

1.1 Filter sets used for culture media and buffer filtration

Filter sets consist of: Bricap™ PES (SLE) sterile capsule filters, Lifemeta™ STF TPE Tubing or STT Pt-cured Silicone Tubing, cross fitting, tubing plugs, aseptic connectors

Four Key Design Considerations:

1) Filter Selection
For mycoplasma removal, filters with pore sizes of 0.2/0.1 μm or 0.45/0.1 μm can be selected.
For sterile filtration, filters with pore sizes of 0.45/0.2 μm are available.

2) Membrane Specifications
Select the appropriate membrane material and filter size based on the media or buffer properties, volume, and loading.

3) Selection of Tubing & Connections before filter
The tubing and connectors before filter should match the outlet of the storage container, typically 1 1/2”Tri-Clamp fittings or quick connectors. For short-time filtration, cost-effective silicone transfer tubing is a cost-effective option.

4) Post-Filter Aseptic Connections & Disconnections
Options include aseptic connectors, aseptic disconnectors, metallic sleeve, and thermoplastic tube welding. Thermoplastic tube welding is the most widely adopted method.

Cobetter’s fully self-produced Lifemeta™ STF thermoplastic tubing features low extractables and low cytotoxicity.

1.2 Transfer sets used for fed-batch culture

Two Key Design Considerations:

1) Aseptic Connection of Feed Ports
Thermoplastic tube welding is typically preferred for aseptic connections.
If prolonged pumping is required, a pump tubing segment with an appropriate diameter can be added.

2) Feed Line Configuration
One end of the feed line can be designed with an aseptic connector to ensure compatibility with the upstream tubing’s terminal fitting.

Single-use media bottle assemblies used for fed-batch



Four Key Design Considerations:

1) Media Bottle Selection
Choose appropriate bottle material and volume based on feed liquid properties and quantity.
PETG material for routine storage and transfer; PC material when freeze storage is required.

2) Aseptic Feed Port Connection
Thermoplastic tube welding is standard for aseptic connections. For extended pumping, add a pump-compatible tubing segment with proper diameter.

3) Dip Tube Configuration
Use unmarked silicone tubing (no surface printing) for liquid contact. Tube length should extend to bottle bottom and angled cut at tube end.

4) Bottle Venting
All bottles should be equipped with venting filters.

1.3 Multi sampling bags and bottles for real-time and scheduled monitoring

Five Key Design Considerations:

1) Sampling Bags or Media Bottle Options
Available in various sizes of sampling bags or meidia bottles. Customized designs available upon requirements. Media bottles require integrated venting filters.

2) Container Configuration
Quantity determined by customer needs (fully customizable).
For ≤10 containers: Multi-port sampling bags/bottles.
For >10 containers: Connectable modular systems for easier packaging and handling.

3) Sampling Methods
Matched to upstream tubing terminal connections, can select aseptic connectors or sampling needles (require 1 1/2”Trip-Clamp sampling ports for sterile connection to stainless containers).

4) Aseptic Disconnection Methods
Can use aseptic disconnectors or Metal sleeves with pinch clamps.

5) Post-Disconnection Sampling
Needle-based sampling, needle-free samplers, luer-lock sampling. Selection depends on user requirements.

2. Filtration, Separation and Purification

The downstream bioprocessing involves multiple critical steps, including depth filtration, chromatographic purification, viral removal, and ultrafiltration. These process steps are essential for ensuring the purity and safety of modern therapeutic-grade products. 

Depth Filtration Tubing Assemblies

Chromatography CIP Tubing Assemblies

Virus Filtration Tubing Assemblies

Ultrafiltration Tubing Assemblies

Three Key Design Considerations:

1) Tubing Selection
Select pressure-resistant rigid tubing for high-pressure applications. Use pump tubing for peristaltic pump operations.

2) Flow Path Configuration
Choose tubing ID (e.g., 3/4" or 1") based on working flow rates. For large-diameter tubing with hose barb connections, secure with stainless steel clamps and reinforce with nylon cable ties for enhanced safety.

3) Pressure Monitoring Options
Instrumentation tee and pressure sensor. 
Instrument tee features 1 1/2”trip-clamp connection with welded membrane for system integrity. With installation of diaphragm pressure gauges (non-contact design) can achieve pressure monitoring. 

Cobetter self-produced pressure sensor is compatible with major brand monitoring systems. Inlet and outlet connections are mostly 3/4”Trip-Clamp or 1 1/2”Tri-Clamp fittings or quick connectors.

3. Formulation Filling

Six Key Design Considerations:

1) Final Filter Selection
Choose appropriate terminal filters based on fluid properties and process parameters.

2) Pressure Monitoring Options
Flexible configuration with instrument tees or pressure sensors as required.

3) Multiple options available

• 3/4”Tri-Clamp fitting or 1 1/2”Tri-Clamp fitting
• Quick connectors
• Aseptic connectors

4) PUPSIT Design
EU GMP Annex 1 includes a requirement for Pre-Use Post Sterilisation Integrity Test or PUPSIT of sterilizing-grade filters used in liquid drug product filtration. PUPSIT is a crucial step in ensuring the sterility of drug products.

Select PUPSIT filters based on sterilizing-grade filter integrity test parameters.
Customize waste systems (vent/effluent bags) according to integrity test requirements.
Optional top-flush bags available for specific process needs.

5) Selection of Pump Tubing Based On

• Peristaltic pump specifications
• Required flow rates

6) Selection of Filling Needle Based on

• Fill volume requirements
• Dosing accuracy specifications
• Compatibility with filling equipment

Conclusion

Single-use systems (SUS) offer significant advantages over traditional stainless-steel systems, including lower upfront costs, elimination of cleaning validation, and accelerated R&D/production timelines. These systems are now widely used in biopharmaceutical production, such as vaccines, antibodies, gene therapies, and cell therapies. 

Cobetter Lifecube™ single-use solutions are manufactured in ISO 9001:2015 quality management systems and compliant with GMP guidelines. We have 11 ISO 7/8 class production lines and 1 fully ISO 4.8 class line. Designed to deliver efficient, regulatory-ready solutions for biopharmaceutical customers.