Following the best cryopreservation protocols helps to ensure cell health and viability during and after long-term storage. But common errors we make in the lab can unknowingly put our samples at risk.
What practices should you follow to safeguard your cryopreserved cells, so they are available when you need them?
Want to learn more? Explore our on-demand webinar: The Seven Keys to Safeguarding Your Cryopreserved Cells, in the Cell Culture Café
Overfilled cryogenic tubes?
Simple errors like overfilling cryogenic tubes or using the wrong cooling rate can jeopardize the integrity of the cryo-tubes and ultimately the cells. The cooling rate has other effects as well. Cool too fast and intracellular ice can form. Cool too slowly and cells may dehydrate and suffer more osmotic imbalance. When followed properly, your freezing techniques can result in a cell viability of 90 percent.
Safety tip: Understand the risks of freezing at the liquid phase of liquid nitrogen. Incorrect handling can lead to explosions or biohazard leaks, causing injury. Introducing samples at the vapor phase is a safer choice, but, if you must introduce them at the liquid phase, wear proper protection and consider consumables specifically designed for this function.
If you don’t require the ultra-low temperatures of liquid nitrogen, another option is an electric freezer with a liquid nitrogen backup. It can achieve temperatures of 135℃.
Understand cooling rates
Also, as we’ve discussed previously, the right cooling rate is a critical factor in minimizing the formation of intracellular ice. While 1℃ per minute is a good general guideline, be sure to refer to the literature for both the optimal cooling rate and best agent or agents for your culture.
Take a look at our Guide for Proper Cryogenic Preservation for more on specific cultures and their needs.
More on safe cryopreservation
There are many variables involved in planning for cryopreservation in your cell culture process—equipment, agents, cooling protocols, and more. Learn more about safety and success in cryopreservation in Thermo Fisher Scientific’s on-demand webinar, The Seven Keys to Safeguarding Your Cryopreserved Cells, in the Cell Culture Café.