Medium 199 With Earle's salts, 25mM HEPES buffer and L-Glutamine Without Sodium bicarbonate is supplied by HiMedia. It is available in the form of an off-white to creamish white homogenous powder. The pH without Sodium Bicarbonate is between 4.8 -5.4 whereas the pH with Sodium Bicarbonate is between 6.6 -7.2. The osmolality without Sodium Bicarbonate is in the range of 265.00 -305.00 Osm/Kg H20 whereas the osmolality with Sodium Bicarbonate 310.00 -350.00 Osm/Kg H20. It is advisable to store this product between 2-8C. Media composition (in mg/L) is as follows:

Calcium chloride dihydrate (265.00)

Ferric nitrate nonahydrate (0.720)

Magnesium sulphate anhydrous (97.72)

Potassium chloride (400.00)

Sodium acetate anhydrous (50.00)

Sodium chloride (6800.00)

Sodium dihydrogen phosphate anhydrous (122.00)

Amino acids

Ascorbic acid (0.05)

Calciferol (0.10)

Choline chloride (0.50)

D-Biotin (0.01)

D-Ca-Pantothenate (0.01)

DL-Tocopherol phosphate disodium salt (0.01)

Folic acid (0.01)

Menadione (0.01)

Nicotinamide (0.02)

Nicotinic acid (0.02)

Pyridoxal hydrochloride (0.02)

Pyridoxine hydrochloride (0.02)

Retinol Acetate (0.14)

Riboflavin (0.01)

Thiamine hydrochloride (0.01)

i-Inositol (0.05)

p-Amino benzoic acid (PABA) (0.05)

Adenine sulphate (10.00)

Adenosine triphosphate (1.00)

Adenosine monophosphate (0.20)

Cholesterol (0.20)

Deoxyribose (0.50)

Glucose (1000.00)

Glutathione reduced (0.05)

Guanine hydrochloride (0.30)

HEPES Buffer (5958.00)

Hypoxanthine (0.35)

Phenol red (15.00)

Polysorbate 80 (4.90)

Ribose (0.50)

Thymine (0.30)

Uracil (0.30)

Xanthine (0.34)

Medium 199 was the first nutritionally defined medium developed by Morgan, Morton, and Parker in 1950. This complex medium was formulated specifically for nutritional studies on primary chick embryo fibroblasts in the absence of any additives. It was observed that explanted tissue could survive in Medium 199 without serum but long-term cultivation of cells required supplementation of the medium with serum. When supplemented with serum, this medium can be used for growth of a wide variety of cells. Medium 199 is presently used for the maintenance of non-transformed cells, vaccine and virus production and primary explants of epithelial cells. This product contains Earle's salts, 25mM HEPES buffer and L-glutamine. HEPES is a zwitterionic buffer having a pKa of 7.3 at 37C, which prevents the initial rise in pH that tends to occur at the initiation of a culture and increases the buffering capacity of the medium.