Eagle's minimal essential medium
Minimal Essential Medium is a synthetic cell culture medium developed by Harry Eagle first published in 1959 in Science that can be used to maintain cells in tissue culture. It is based on 6 salts and glucose described in Earle's salts in 1934:, supplemented with 13 essential amino acids, and 8 vitamins: thiamine, riboflavin, nicotinamide, pantothenic acid, pyrodoxine, folic acid, choline, and myo-inositol.
Many variations of this medium have been developed, mostly adding additional vitamins, amino acids, and/or other nutrients.
Eagle developed his earlier "Basal Medium Eagle" in 1955–1957 on mouse L cells and human HeLa cells, with 13 essential amino acids and 9 vitamins added. BME contains biotin, which Eagle later found to be superfluous. His 1959 "Minimal Essential Medium" doubles the amount of many amino acids to "conform more closely to the protein composition of cultured human cells. This permits the cultures to be kept for somewhat longer periods without refeeding".
DMEM was originally suggested as Eagle's medium with a 'Fourfold concentration of amino acids and vitamins' by Dulbecco and Vogt published in 1959. The commercial version of this medium has additional modifications detailed below.
α-MEM is a medium based on MEM published in 1971 by Clifford P. Stanners and colleagues. It contains more non-essential amino acids, sodium pyruvate, and vitamins compared with MEM. It can also come with lipoic acid and nucleosides.
Glasgow's MEM is yet another modification, prepared by lan MacPherson and Michael Stoker.
Composition
One liter of each medium contains :| Medium | BME | MEM | MEMa |
| Glycine | 50 | ||
| L-Alanine | 25 | ||
| L-Arginine hydrochloride | 21 | 126 | 126 |
| L-Asparagine-H2O | 50 | ||
| L-Aspartic acid | 30 | ||
| L-Cysteine hydrochloride-H2O | 100 | ||
| L-Cystine 2HCl | 16 | 31 | 31 |
| L-Glutamic Acid | 75 | ||
| L-Glutamine | 292 | 292 | 292 |
| L-Histidine | 8 | 31 | |
| L-Histidine hydrochloride-H2O | 42 | 42 | |
| L-Isoleucine | 26 | 52 | 52 |
| L-Leucine | 26 | 52 | 52 |
| L-Lysine hydrochloride | 36.47 | 73 | 73 |
| L-Methionine | 7.5 | 15 | 15 |
| L-Phenylalanine | 16.5 | 32 | 32 |
| L-Proline | 40 | ||
| L-Serine | 25 | ||
| L-Threonine | 24 | 48 | 48 |
| L-Tryptophan | 4 | 10 | 10 |
| L-Tyrosine disodium salt dihydrate | 26 | 52 | 52 |
| L-Valine | 23.5 | 46 | 46 |
| Ascorbic acid | 50 | ||
| Biotin | 1 | 0.1 | |
| Choline chloride | 1 | 1 | 1 |
| D-Calcium pantothenate | 1 | 1 | 1 |
| Folic Acid | 1 | 1 | 1 |
| Niacinamide | 1 | 1 | 1 |
| Pyridoxal hydrochloride | 1 | 1 | 1 |
| Riboflavin | 0.1 | 0.1 | 0.1 |
| Thiamine hydrochloride | 1 | 1 | 1 |
| Vitamin B12 | 1.36 | ||
| i-Inositol | 2 | 2 | 2 |
| Calcium Chloride | 200 | 200 | 200 |
| Magnesium Sulfate | 97.67 | 97.67 | 97.67 |
| Potassium Chloride | 400 | 400 | 400 |
| Sodium Bicarbonate | 2200 | 2200 | 2200 |
| Sodium Chloride | 6800 | 6800 | 6800 |
| Sodium Phosphate monobasic | 140 | 140 | 140 |
| D-Glucose | 1000 | 1000 | 1000 |
| Lipoic Acid | 0.2 | ||
| Phenol Red | 10 | 10 | 10 |
| Sodium Pyruvate | 110 |