Chemically-defined CHO media comes in two forms: premixed liquids and dry powders. When deciding which type of media to use, a researcher must decide on the amount of media needed for the project. Liquid media allows for direct use in small format bioreactors, flasks and microplates. Powdered media must be reconstituted into solution, however the shipment and storage of powders is easier and cheaper, so it is often used for larger studies and volumes. Many organizations have dedicated media prep teams and labs to mix formulations of powdered media to simplify the workflows of cell culture and upstream process development labs. Running a quick fresh media assay prior to feeding the culture ensures consistency of the media components when scaling up or during the transition between liquid-to-dry media blends.
In this comparison of dry and liquid CHO media composition, differences of up to 20% on various components are shown, with liquid media containing higher concentrations that then dry media. CHO media composition can significantly impact cell production and growth at these levels.