Hi Ivan,

I am sorry. I don't understand your question. Why CO2 will be produced if you only use H2O in your microfluid device? When you pump cell culture medium which contains NaHCO3 and heat the medium will cause CO2 produce. Prevent CO2 bubble formation is difficult.  Could you detail demonstrate your question?

Best wishes!

Chao

Thank you Chao. You're right, the device will be used to grow E. coli at 37 C. MiliQ water is just a control and won't have nearly as much CO2 as the culture because when the microorganisms grow, they breathe and produce CO2. What I am wondering is whether there is any way to get rid of the CO2 without opening the system (say through a breath-easy membrane)? I thought perhaps there could be a buffer that could do the job. But apparently this cannot be done around neutral pH (to grow the microorganisms), is that correct?