Minimum Essential Medium (MEM) α is widely used for mammalian cell culture as well as selection for transfected DHFR negative cells. MEM α can be used with a variety of suspension and adherent mammalian cells, including keratinocytes, primary rat astrocytes, and human melanoma cells. We offer a variety of Gibco™ MEM α modifications for a range of cell culture applications. Find the right formulation using the media selector tool.
The complete formulation is available.

Gibco™ MEM α is a modification of Minimum Essential Medium (MEM) that contains non-essential amino acids, sodium pyruvate, lipoic acid, B₁₂, biotin, and ascorbic acid. MEM α is available without nucleosides for use as a selection medium for DG44 and other DHFR negative cells. This product is made with Earle’s salts.

cGMP Manufacturing and Quality System
Gibco™ MEM α is manufactured at a cGMP compliant facility, located in Paisley, Scotland, UK. The facility is registered with the FDA as a medical device manufacturer and is certified to the ISO 13485 standard. For supply chain continuity, we offer a comparable Gibco™ MEM α product made in our Grand Island facility (11900-024). This facility is registered with the FDA as a medical device manufacturer and is certified to the ISO 13485 standards.

MEM α contains no proteins, lipids, or growth factors. Therefore, MEM α requires supplementation, commonly with 10% Fetal Bovine Serum (FBS). MEM α uses a sodium bicarbonate buffer system (2.2 g/L) and therefore requires a 5-10% CO₂ environment to maintain physiological pH.

Powder forms of Gibco™ cell culture medium require sodium bicarbonate supplementation, pH adjustment, and filtration at the time of preparation (see protocol for details).