Reduce variation in cell based assays and minimize the edge effect with the Microplate Stability Chamber

When placed inside a standard or CO₂ incubator, this stability chamber works to reduce the variations of cell based assays often experienced within microwell plates. The chamber uses the incubator heat and atmosphere to create a homogeneous microenvironment for microwell plates rather than the heterogeneous environments created in traditional incubators. High humidity within the chamber eliminates evaporation from the plates that causes the edge effect. The thick anodized aluminum shelf distributes heat evenly to up to six plates for excellent temperature uniformity. The chamber includes a fan powered by a 120V or 230V power converter.

APPLICATION

The Microplate Stability Chamber arose from years of frustration of working will cell culture in 96 well plates. In our laboratory (as with many others) it was readily observed that the edge wells and especially corner wells of plates all generated data statistically different from wells located on the interior of the plate. This "edge effect" can make 26 of the 96 wells useless. We decided to solve this problem and started by examining incubators and how they affected cells. We found that all incubators were insufficiently designed to prevent evaporation from the edge wells and that within an incubator, conditions varied between shelves and even between locations on the same shelf. This variation within the chamber directly impacts cell culture for cell based assays, at times more than doubling the CVs of the assays. The chamber also creates stability for general types of tissue culture.

The Microplate Stability Chamber addresses the shortcomings of incubators by creating a high humidity, temperature stable environment. A heavy aluminum shelf with six recessed areas for plates provides for even heat distribution across the chamber. A fan blows air across a water reservoir which then saturates the atmosphere. This prevents evaporation and creates a homogeneous temperature which is especially valuable when performing cell based assays. The lid on the chamber is not air tight, thus gases from the incubator, such as 5% carbon dioxide, can diffuse into the chamber. Likewise, humidity for the chamber can increase the overall humidity of the incubator.

Recovery of humidity in the chamber after the unit is opened is fast, especially when compared to the incubator. The following graph shows that 90% relative humidity can be reached within a minute of closing the chamber, and nearly saturating relative humidity in 2 minutes. The incubator alone is slow in recovering while an incubator with a chamber will reach saturation in about 10 minutes.

This chamber and similar designs have been in use in our laboratory since 1996.

Products Product Number List Price

Microplate Stability Chamber, 120V, 50/60Hz TR-930212 $883

Microplate Stability Chamber, 230V, 50/60Hz TR-930213 $883

Aluminum Microplate Tray TR-930214 $317