Data in Motion: Freezing Curves in the Digitcool


Written by Anne-Marie McAnelly

When using a controlled rate or programmable freezer we aim to have the sample freezing curve to follow a known, optimal theoretical freezing curve programmed into the equipment. To achieve this, curves are closely monitored with temperature probes.

The Digitcool programmable freezer contains two temperature probes, one to monitor the air temperature in the chamber, and one sample probe, to monitor the sample's freezing rate.  When plotted, the resulting curves, plus the theoretical curve, result in a three-curve chart that documents a slow freezing cycle.  

The theoretical curve is the guiding path that you want the sample to follow. The Digitcool’s standard report documenting a freezing cycle displays the theoretical curve for the user to perform a quality control check of the freezing event. 

The chamber probe curve monitors how the air in the freezer’s chamber changes in temperature during the freezing process. This is important for the entire inventory of samples contained within the chamber during the freezing cycle.  

The sample probe curve answers specific questions as to how the sample reacted during the cycle. When monitoring this curve, you want your sample to achieve the four main freezing stages: liquid cooling, liquid to crystalline, cooling to crystal state and stable stage. This curve shows you precisely how the sample reacts to the changing temperatures and each of the different stages.

Each of these curves have value on their own; but together they form a complete power team that can provide the necessary data documenting the freezing of valuable samples. They allow the user to track in real time and confirm that the theoretical freezing curve can provide the essential environment to ensure premium sample quality to a specific sample.

The Digitcool freezer is the leading controlled rate freezer in animal reproduction centers.  When installed, our customers are shown how to adapt “base” theoretical curves to their specific needs. For example, curves may have to be tailored to specific media extenders; specific cryoprotectant molecules or content.  Likewise, the curves suggested by IMV Technologies may be adapted to specific sample needs, goal temperatures or cooling rate.  The flexibility of this freezer, and its ability to record data are just some of the powerful advantages that this freezer offers. 

Talk to your IMV Technologies representative to learn more about the Digitcool line of programmable freezers for animal semen, and beyond. 

The views expressed in IMV Technologies’ blog do not necessarily represent the views of the IMV Technologies Group but solely those of the blog post’s author