During the past two decades, researchers have been seeking serum-free media for the culturing of a wide range of cell lines and even primary cells. With the supplementation of growth factors and hormones, researchers discovered that a 1:1 mixture of DMEM and Ham's F-12 Nutrient Mixture was beneficial to a wide ranges of cells. HEPES buffer is included in the formulation at a final concentration of 15 mM to compensate for the loss of buffering capacity incurred by eliminating serum. DMEM/F12 with L-glutamine and HEPES is a sterile, liquid medium which contains essential and non-essential amino acids, vitamins, organic and inorganic compounds, hormones, growth factors and trace minerals. It is well suited for supporting the growth of a broad range of mammalian cell lines.