Dulbecco's Modified Eagle's Medium (DMEM) is modified to contain 4 mM L-glutamine, 4500 mg/L glucose, 1 mM sodium pyruvate, and 1500 mg/L sodium bicarbonate.
This reduced level of sodium bicarbonate (NaHCO3, 1.5 g/L) is intended for use in 5% CO2 in air. Additional sodium bicarbonate may be required for use in incubators containing higher percentages of CO2.