All Photos(1)



Antifoam 204

aqueous emulsion for bacterial and mammalian systems

organic antifoam
MDL number:

Quality Level


emulsion (aqueous)


100% (organic)


1.01 g/mL at 25 °C



storage temp.

room temp


(Mammalian (suspension))
bacteria (fermentation)

Looking for similar products? Visit Product Comparison Guide

General description

Antifoam 204 is an organic antifoam used to prevent or minimize foaming in both microbial fermentation systems and mammalian suspension cultures. Control of foaming minimizes damage to the cells, resulting in increased protein/antibody production.


Suitable for preventing or minimizing foaming in microbial fermentation systems and mammalian suspension cultures.
Antifoam 204 has been used:
  • in the expression and purification of PUL (PLAP, Ufd3p, and Lub1p) domain
  • in fed-batch fermentation
  • to prevent bubble formation due in aeration in Luria Bertani (LB) culture medium for bacterial growth
  • in the batch fermentation with mineral medium


Antifoam 204 is a 100% active components and a mixture of non-silicone organic defoamers in a polyol dispersion.

Other Notes

Contains 100% active components and is a mixture of non-silicone organic defoamers in a polyol dispersion. Can be sterilized repeatedly.

Preparation Note

For use in microbiological media Sigma recommends a starting concentration of between 0.005% and 0.01%.
The optimal amount of antifoam required for various applications will need to be determined. Antifoam 204 is soluble in methanol, ethanol, toluene, xylene, perchloroethylene, and cold water at temperatures below 15 °C. It is insoluble in warm water and ethylene glycol.

Storage Class Code

10 - Combustible liquids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US), Eyeshields, Gloves

Certificates of Analysis (COA)

Search for Certificates of Analysis (COA) by entering the products Lot/Batch Number. Lot and Batch Numbers can be found on a product’s label following the words ‘Lot’ or ‘Batch’.

Already Own This Product?

Documents related to the products that you have purchased in the past have been gathered in the Document Library for your convenience.

Visit the Document Library

Difficulty Finding Your Product Or Lot/Batch Number?

Product numbers are combined with Pack Sizes/Quantity when displayed on the website (example: T1503-25G). Please make sure you enter ONLY the product number in the Product Number field (Example: T1503).


Product Number
Pack Size/Quantity

Additional examples:





enter as 1.000309185)

Having trouble? Feel free to contact Technical Service for assistance.

Lot and Batch Numbers can be found on a product's label following the words 'Lot' or 'Batch'.

Aldrich Products

  • For a lot number such as TO09019TO, enter it as 09019TO (without the first two letters 'TO').

  • For a lot number with a filling-code such as 05427ES-021, enter it as 05427ES (without the filling-code '-021').

  • For a lot number with a filling-code such as STBB0728K9, enter it as STBB0728 without the filling-code 'K9'.

Not Finding What You Are Looking For?

In some cases, a COA may not be available online. If your search was unable to find the COA you can request one.

Request COA

Our team of scientists has experience in all areas of research including Life Science, Material Science, Chemical Synthesis, Chromatography, Analytical and many others.

Contact Technical Service