In cell culture, a humidified atmosphere refers to the environment inside an incubator that maintains a controlled level of humidity, typically around 95%. This environment is crucial for the growth and maintenance of cells in vitro, as it helps to prevent the evaporation of culture medium and maintain a stable pH.
The majority of mammalian cells are cultured at 37°C with a 5% CO2 atmosphere, which helps to maintain the physiological pH of the culture medium, usually around 7.2 to 7.4. The presence of water vapor in the incubator creates a saturated or near-saturated atmosphere, preventing the evaporation of water from the culture medium.
When setting up a humidified incubator, follow these general guidelines:
- Make sure the incubator is clean and sterile before use. Regularly clean and decontaminate the incubator to prevent microbial contamination.
- Place a water tray or pan at the bottom of the incubator, and fill it with sterile, deionized water. This will provide a source of humidity within the incubator.
- Set the temperature of the incubator to 37°C (or the appropriate temperature for your specific cell line or experimental setup).
- Adjust the CO2 concentration to 5% (or the appropriate level for your specific cell line or experimental setup).
- Allow the incubator to equilibrate for several hours or overnight before placing cells inside to ensure temperature, humidity, and CO2 levels have stabilized.
- Regularly monitor and refill the water tray as needed, and check the temperature and CO2 levels to ensure they remain within the desired range.
Maintaining a humidified atmosphere in the incubator is essential for the successful growth and maintenance of cells in vitro. Always follow the specific requirements of your cell line and use aseptic techniques to prevent contamination.
