Hello Fabián Alonso Arce-Rodríguez

CO2 is required for cell cultures as it helps to maintain a stable physiological pH through the bicarbonate buffering system. CO2 fluctuations will hamper cell growth as it may affect the optimum physiological pH.

I would suggest you avoid using the external CO2 in this case. Instead, you can use EMEM powder medium without bicarbonate and supplement it with 10mM to 25mM HEPES and adjust pH to 7.2 - 7.4, and incubate the culture at 28°C in the humidified incubator till the problem of CO2 fluctuation is solved.

Best,

No, it can not survive, try to stabilize the CO2 level.

HEPES can support cells without CO2 for 1-2 days, handy for time-lapse microscopy without CO2 on stage chamber, but not really solve an issue of stable CO2. In practice you still need a CO2 incubator to grow cells. In the case of unstable CO2, it's worse as high CO2 values harm cells more than low CO2 due to Ph fluctuations. You need to have a reliable incubator to do cell work.

In tissue culture, you should use the optimum conditions for the cells to grow. Thus, solve the problem or all your results will be far away the truth.

You have to fix your CO2 incubater to obtain real results