When it comes to media selection for cell culture, it can be an overwhelming task as there are multiple options available to choose from. Traditionally, cell culture media consists of amino acids, vitamins, inorganic salts and a carbon source for energy, provided by a basal media. In addition, to promote cell growth this formulation requires to be supplemented by a growth promoting agents such as growth factors. Therefore, the proper selection of both basal media and supplement is a critical step to ensure the success of your experiment.
DMEM/F-12 (Dulbecco’s Modified Eagle’s Medium / Nutrient Ham’s Mixture F-12) is a widely used basal media that supports the growth of many mammalian cells, including maintenance of embryonic and induced pluripotent stem cells in the undifferentiated state. However, the addition of certain components within DMEM/F-12 can vary across vendors. The following are some components that are important to consider when selecting your basal media.
- HEPES: Growth of cells in culture can have an effect the pH of the medium, therefore it is necessary to have a buffer that can maintain a proper environment for the cells. HEPES is a buffering agent that helps maintain a pH 7.2-7.4, which is optimal for most cells.
- Sodium bicarbonate: Similarly, to HEPES, sodium bicarbonate helps stabilize the pH of media when using 5-10% CO2, which is a common atmospheric condition when culturing cells.
- ւ-alanyl-ւ-glutamine: ւ-Glutamine is an essential amino acid and it functions as a major source of energy for the cells. However, it quickly degrades overtime and it can produce toxic by-products. ւ-alanyl-ւ-glutamine serves as a direct replacement for L-Glutamine, as it is more stable in media during storage or incubation.
Price PJ. Best practices for media selection for mammalian cells. In Vitro Cell Dev Biol Anim. 2017 Sep;53(8):673-681. doi: 10.1007/s11626-017-0186-6. Epub 2017 Jul 19. PMID: 28726187.