Why CO2 is needed in cell culture?

The pH of a typical cell culture solution is between 7.0 and 7.4. Since the carbonate pH buffer system is a physiological pH buffer system (it is an important pH buffer system in human blood), it is used to maintain a stable pH in most cultures. a certain amount of sodium bicarbonate often needs to be added when preparing cultures with powders. For most cultures that use carbonate as a pH buffer system, in order to maintain a stable pH, the carbon dioxide in the incubator needs to be maintained between 2-10% to maintain the concentration of dissolved carbon dioxide in the culture solution. At the same time the cell culture vessels need to be somewhat breathable to allow for gas exchange.

Does the use of other pH buffer systems eliminate the need for a CO2 incubator? It has been found that due to the low concentration of carbon dioxide in the air, if the cells are not cultured in a carbon dioxide incubator, the HCO3- in the culture medium will be depleted, and this will interfere with the normal growth of the cells. So most of the animal cells are still cultured in a CO2 incubator.

Over the past few decades, the fields of cell biology, molecular biology, pharmacology, etc. have made amazing strides in research, and at the same time, the application of technology in these fields has had to keep pace. Although the typical life science laboratory equipment has changed dramatically, the CO2 incubator is still an important part of the laboratory, and is used for the purpose of maintaining and promoting better cell and tissue growth. However, with advances in technology, their function and operation have become more precise, reliable and convenient. Nowadays, CO2 incubators have become one of the routine instruments commonly used in laboratories and have been widely used in research and production in medicine, immunology, genetics, microbiology, agricultural science, and pharmacology.

A CO2 incubator creates an environment for better cell/tissue growth by controlling the surrounding environmental conditions. The result of the condition control creates a stable condition: e.g. constant acidity/alkalinity (pH: 7.2-7.4), stable temperature (37°C), high relative humidity (95%), and a stable CO2 level (5%), which is why researchers in the above fields are so enthusiastic about the convenience of using a CO2 incubator.

In addition, with the addition of CO2 concentration control and the use of a microcontroller for precise temperature control of the incubator, the success rate and efficiency of cultivation of biological cells and tissues, etc., have been improved. In short, CO2 incubator is a new type of incubator that cannot be replaced by ordinary electric thermostat incubator in biological laboratories.