Last Updated on November 19, 2023

Overview of the Strex Cell Controlled-Rate Freezer

Today we’ll cover some features of Strex’s CytoSensei, our liquid nitrogen-free controlled rate freezer, and one of our most popular items!

What is controlled-rate freezing?

Controlled rate freezing is the method of slowly freezing cells or samples to long-term storage temperatures, around -80 degrees while maintaining viability. Non-controlled options like liquid nitrogen can cause contamination and damage from ice crystals; inconsistent results are also an issue when preserving many samples with this technique. Preserving precious cells in a controlled manner will prevent many issues stemming later on.

How the CytoSensei works

The device includes the cables, an external temperature sensor. The software is preloaded onto a USB stick, with which we recommend you copy it to your PC before using the freezer. This model can hold 50 1-2 mL cryotubes; however, Strex will custom manufacture cryocells compatible with any size of tubes or bags you might need.

To start a freezer protocol, make sure that all connections are secured and the power switch on the back of the unit is switched on. Boot up Strex Freezer control software. If you receive an error message, check your connections once again and ensure you’re not running it from a USB stick.

Open a program, or create and save a new protocol. Sample IDs can be recorded in the software to keep track of large quantities. Once you’ve chosen your desired protocol, hit the start freeze button; when you see the light interface change on the freezer, it means that freezing has started up. As time goes by and cooling happens (an hour into this sample), we notice that there is a steady decrease in temperature – this is what should happen!

At the end of a protocol, freezer software can generate PDF reports for record-keeping. Be sure to start the warming cycle once you have removed your samples for long-term storage and ready the freezer for another cycle. Samples should not be thawed with the heater function, as this may affect viability.

Summary: Controlled Rate Freezer

The CytoSensei is a liquid nitrogen-free controlled rate freezer that reduces the risk of contamination, makes freezing easy and hazard-free, and saves your precious samples. It comes in two sizes to accommodate tubes, cryovials, or bags as well!

With a programmable freeze-down cycle, you are given control over the viability and have no need for large liquid nitrogen tanks.