Mimicking an in vivo environment is one of the most difficult tasks in cell culture, but CO2 incubators make the process much easier by maintaining stable environmental conditions. Cells are very sensitive to changes in temperature, pH, and humidity, and constantly opening and closing the door can result in atmospheric fluctuations. These changes can affect cell health, and it’s therefore important to follow a few simple guidelines when looking after your incubator.
- Monitor CO2 levels
The CO2 concentration in your incubator works with your growth media to ensure optimal pH for growth. A robust and modern CO2 sensor can be quite reliable but it’s a good idea to use an external gas analyzer to ensure the reading is accurate.Check between 1 and 3 months. If the CO2 levels are not accurate, run an Autostart cycle (if available) or contact a factory trained service specialist for help.
- Eliminate contamination
Every lab contains some contaminants, but maintaining good lab practice will minimize the chances of them making their way into your incubator and infecting or disrupting your culture. When cleaning the incubator, make sure the disinfectant you choose doesn’t contain harsh chemicals that could affect the growth of your culture or that could corrode your incubator chamber. Good choices include 70% ethanol or a quaternary ammonium based disinfectant.
- Maintain humidity
Inadequate humidity levels result in evaporation of water from growth media, and the remaining nutrients becoming too concentrated. You can prevent this from happening by ensuring sterile distilled water is kept at a high level in the water tray at the bottom of the incubator. Change the water completely about one time per week to limit microorganisms colonizing the water.
- Change the HEPA filter yearly
A HEPA filter which is positioned inside the incubator chamber and is driven by a circulating fan will capture all types of microorganisms and dust particles. Some can even capture volatile organic compounds which could make your cells sick. Look for a model which will filter the entire chamber air volume every 60 seconds to achieve ISO Class 5 cleanroom conditions in 5 minutes following even a long 30 second door opening.
It doesn’t take much for your cells to notice a change in environmental conditions, and if they do, it’s likely to have a pronounced effect on your culture. You can prevent this from happening by following these tips, as well as implementing a systematic cleaning schedule to keep on top of your incubator’s maintenance requirements.