MEM (Minimum Essential Medium) is one of the most commonly used basal mediums for supporting the growth of many suspension and adherent mammalian cells. MEM medium is a more nutrient rich version of basal medium eagle (BME) media, and is suitable for Hela, BHK-21, 293, HEP-2, HT-1080, MCF-7, fibroblasts and primary rat astrocytes. There are some other modifications of MEM followed, including with or without non-essential amino acids (including L-Alanine, L-Glutamic acid, L-Asparagine, L-Aspartic acid, L-Proline, L-Serine, and Glycine), addition of ribonucleosides and deoxyribonucleosides, with Earle’s salts for use in a CO2 incubator or with Hank’s salts for use without CO2. This product is made with Earle’s salts, includes non-essential amino acids, no addition of ribonucleosides and deoxyribonucleosides.

MEM contains no proteins, lipids, or growth factors. Therefore, MEM requires supplementation, commonly with 10% Fetal Bovine Serum (FBS). MEM uses a sodium bicarbonate buffer system (2.2 g/L), and therefore requires a 5–10% CO2 environment to maintain physiological pH. All raw material components used for cell culture media products are screened through using strict quality control testing. cell culture media are manufactured at a cGMP-compliant facility using water for injection, filtered through final 0.1 μm sterile filtration and aseptic filled in a Hundred-stage FFU. The filter integrity tests are performed before and after filtration. Each lot of cell culture media is subjected to sterility test, pH, osmolality, and cell culture test.