When do you need to use a Transfer Cap?

Transfer Caps can be used whenever you need to aseptically transfer suspension cell culture or media from one vessel to another. For example, scaling up suspension cell culture to a larger vessel, such as a bag or bioreactor or adding media to a flask.

What are the differences between Inversion Transfer and Bidirectional Transfer Caps?

Inversion Transfer Caps use gravity instead of a pump to move suspension cell culture or media from an Optimum Growth®flask to another vessel. Simply invert the flask with Inversion Transfer Cap onto a ring stand at least 18” above the receiving vessel and let gravity do the work.

There are 4 standard Inversion Transfer Caps available: 1/4″ OD barbed Quick Connect, 7/16″ OD Male Quick Connect, 1/4″ OD C-flex 16 tubing with plug for Tube Fusing, 7/16″ OD C-flex 24 tubing with plug for Tube Fusing and 1/4″ OD C-flex 16 tubing with Male Luer Lock. To ensure sterility, we recommend connecting inside the hood.

Bidirectional Transfer Caps use a peristaltic pump to transfer suspension cell culture or media between the flask and another vessel. Since peristaltic pumps can pump in either direction, the Bidirectional Transfer Cap can be used to move suspension cell culture or media from an Optimum Growth® flask to another vessel such as a bag or a bioreactor as well as from another vessel such as a media bag into the flask.

There are two standard Bidirectional Transfer Caps available: 1/4″ OD C-flex 16 tubing with plug for Tube Fusing and 1/4″ OD C-flex 16 tubing with Male Luer Lock.

What flasks are the Transfer Caps used with?

Transfer Caps are compatible with Thomson 1.6L, 2.8L and 5L Optimum Growth® Flasks. Please note though that transfer caps are not interchangeable between 1.6L, 2.8L and 5L flasks, please ensure that you match the correct Transfer Cap with the selected flask volume. Inversion Transfer Caps can be used to transfer up to 3L and Bidirectional Transfer Caps can transfer up to 4.5L. Please see our technical library for more information on these flasks and their benefits.

What if I need a different kind of tubing attached?

We are happy to accommodate custom orders whenever possible.

How do I know if my tubing is compatible for welding to your tubing?

The C-flex tubing that comes on the Transfer Caps is compatible with most bioreactor bags. We are happy to test a sample of your tubing for welding compatibility.

Can you use the Transfer Caps with all cell lines?

The Transfer Caps are compatible with all suspension cell lines and media types.

What are the benefits to using the Inversion Transfer Caps vs other transfer methods?

The Inversion Transfer Caps use gravity to facilitate transfer rather than pumping. Peristaltic pumping action applies shear forces to cells membranes and can result in reduction of cell viability. Gravity transfer is gentle and maintains high culture viability.

Coupled with Optimum Growth® Flasks, Transfer Caps allow for direct, sterile transfer to your next culture vessel. This eliminates the need for an intermediate transfer flask or bag.

What are the benefits to using the Bidirectional Transfer Caps vs other transfer methods?

The Bidirectional Transfer Caps use a peristaltic pump to facilitate transfer. Since peristaltic pumps can move cell culture media in both directions, the transfer caps can be used to add media to the flask as well as move suspension cell culture out the of the flask.

Coupled with the Optimum Growth® Flasks, Transfer Caps allow for direct, sterile transfer to your next culture vessel. This eliminates the need for an intermediate transfer flask or bag.

Are the Transfer Caps single-use?

Yes. When tube fusing, the tube can be clamped off, cut, and refused to a different vessel. But caps cannot be reused without risk of contamination.

Will the Transfer Caps leak?

No. Provided the specific Transfer Cap is matched to the specific flask volume. Just be sure the cap is securely tightened while still in the hood.

What can I do if the transfer using the Inversion Transfer Caps is slowing down or pulling a vacuum in the flask?

First, be sure you have removed the plug from the air filter. If air has not started to flow through the air filter intake, try injecting some air with a syringe to get it started.

Be sure the flask is elevated at least 18” above the receiving vessel for gravity to work.

Thomson is not affiliated with GE Healthcare Life Sciences® or their products.