Why does DMEM always contain 3.7g/L of sodium bicarbonate? - (Apr/14/2015 )
Hi everyone,
Companies formulate DMEM always with 3.7g/L of sodium bicarbonate. But majority of researchers use only 5% CO2 incubators, which is ideal for media with 1.5-2.2g/L of sodium bicarbonate. 3.7g/L of NaHCO3 requires 10% CO2. So, while most of us use only 5% CO2 incubators and everyone knows this, companies must have a good reason for insisting on 3.7g/L. Do you have an idea on this? Does DMEM have to contain 3.7g/L NaHCO3 for some reason?
People in my lab also use DMEM but they didn't know DMEM requires 10% CO2. I let them know this but they are not willing to change their culture conditions as all of their experiments have been done in 5% CO2 all the time. So I decided to buy DMEM with lower NaHCO3 concentration. I found one from ATCC (1.5g/L), but they have only high glucose DMEM (I use low glucose DMEM). I found powder forms where I can add the desired amount of NaHCO3 but I don't want to spend time on preparation, pH adjustments and sterility issues. Do you have a suggestion about what to do? Should I just ignore these questions in my mind and keep doing what many researchers have been doing wrongly (i.e. using DMEM with 5% CO2)?
Thanks in advance for your replies.
I'm not sure if this is allowed, but I think you can find your answer here:
From this I filter that you're right regarding the bicarbonate concentration and CO2 percentage. Perhaps it's just that this is the standard WoW, and nobody wants to deviate from this as it's 'how it's done'.