Consider Humidity in Your CO₂ Incubator for Excellent Cell Growth

Cell culture applications are rapidly advancing. Cultured cells play a crucial role in various fields such as vaccine and pharmaceutical production, toxicity testing, regenerative medicine, cell therapy, cancer research, immunology, neurology, and more. In these sensitive applications, the integrity and health of cells are of utmost importance.

Humidity is an often-overlooked parameter in cell culture.

Humidity is a crucial factor for cell health, as important as other factors. In a cell culture incubator, balanced growth media supply moisture and nutrients to cells. Maintaining humidity at 85-95% prevents excessive evaporation from the media, which can lead to high concentrations of salts and minerals, causing toxicity and cell death. Evaporation is four times faster at 80% humidity compared to >93%. Restoring high humidity after a door opening is challenging. The figure below illustrates various technologies’ efficiency in recovering humidity.

Low humidity can severely impact cell culture labs.

When water evaporation from cultures happens due to low humidity, the cell cultures used in advanced applications may become unusable and need to be discarded. Since these cells typically take about 24 hours to double, it can take days or weeks to grow enough cells for a single experiment or treatment. Having to repeat experiments or processes due to poor cell growth caused by unfavorable culture conditions can result in substantial financial implications.

Using the correct type of water is very important.

It is important to note that using the wrong type of water for in-chamber humidity can cause damage to your incubator, corroding components such as stainless steel, copper, and glass. This is not due to the quality of the incubator materials, but rather the relative purity of the water. High purity water with low ionic strength, such as deionized (DI), reverse osmosis (RO), or ultrapure Type 1 water, can be corrosive to metals and glass over time. To avoid this, it is recommended to only use sterile, distilled water with a pH between 7 and 9 in your CO₂ incubator.

The design of the humidity system plays a big role in minimizing the risk of contamination.

Thermo Scientific™ Heracell™ VIOS™ 160i and 250i and Thermo Scientific™ Forma™ Steri-Cycle™ i160 and i250 CO₂ incubators feature an integrated water reservoir that is fully covered. This design significantly reduces the likelihood of microorganisms dropping into the water. The front of the cover has an opening for adding fresh, sterile distilled water. During regular use, a pre-filter covers the opening, preventing microbes carried by dust and dirt from entering the water reservoir.

Resources:

Smart notes:

How can using the wrong type of water to provide in-chamber humidity cause corrosion in my CO₂ incubator?

Which incubation parameters are most important for proper cell growth and expression?

Technical note:

Protect cultured cells by limiting contaminants in the humidity water with select Thermo Scientific™ CO2  incubators