What Are Ultra Low Temperature Freezers & What Are They Used For?

Ultra low temperature freezer graphic by CoolMed

In various fields of scientific research and medical applications, the need to preserve valuable biological samples, delicate vaccines, or specialised reagents at extremely low temperatures is crucial.

This is where ultra low temperature freezers (ULT freezers) come into play.

These cutting-edge appliances are designed to achieve and maintain ultra low temperatures, making them essential tools in a range of healthcare and scientific industries.

Understanding Ultra Low Temperature Freezers

Ultra low temperature freezers are specialised refrigeration units designed to reach and sustain extremely low temperatures, typically ranging from -40°C to as low as -86°C. These temperatures are significantly colder than standard household freezers, which typically operate at around -18°C.

ULT Freezer Construction & Features

Ultra low temperature freezers are constructed with robust insulation and advanced cooling systems to ensure efficient and reliable operation at extreme temperatures. They are typically made with stainless steel interiors to provide a clean and durable storage environment. Additionally, these freezers are equipped with tightly sealed doors to prevent temperature fluctuations caused by ambient air intrusion.

At CoolMed, our ULT freezer is designed first and foremost to protect biological samples. The freezer has a net capacity of 80 litres and the temperature is fully adjustable between -40°C to -86°C. The high-quality temperature controller constantly modifies and stabilises the temperature, with the external LED temperature indicator providing accurate information on the inner temperature levels. 

The freezer also features an audible and visual alarm to alert practitioners of any temperature fluctuation.

Applications of Ultra Low Temperature Freezers

Ultra low temperature freezers are commonly used in research laboratories and by biotech companies for a variety of applications. These include:

Biomedical Research

ULT freezers play a crucial role in preserving biological samples such as cell lines, tissues, DNA, RNA, and proteins. These samples are often used in various research fields, including genetics, molecular biology, and drug discovery.

The extremely low temperatures slow down the degradation processes, effectively preserving the samples for extended periods.

Pharmaceutical Storage

Certain vaccines, medications, and other pharmaceutical products often require long-term storage at ultra low temperatures to maintain their stability and efficacy.

For example, Pfizer’s COVID-19 vaccine can be stored for up to 6 months at -70°C, whereas they can only be stored in a regular laboratory freezer for 2 weeks.

Ultra low temperature freezers provide the necessary conditions to store these sensitive drugs, ensuring they remain potent until they are ready for use.

Clinical Laboratories

ULT freezers are extensively used in clinical laboratories for the storage of diagnostic specimens, such as blood, plasma, and serum.

These biological samples usually contain valuable information for disease diagnosis, genetic testing, or research purposes, and must be stored at ultra low temperatures to maintain their integrity.

Assisted Reproductive Technology (ART)

In assisted reproduction techniques, such as in-vitro fertilisation (IVF), oocytes (eggs) and embryos are stored at ultra low temperatures until they are ready for use.

Ultra low temperature freezers provide a reliable environment for the preservation of these delicate reproductive materials, allowing fertility clinics to offer patients improved chances of successful pregnancies.


Ultra low temperature freezers are also used in cryopreservation processes, where biological materials are frozen at extremely low temperatures using cryoprotective agents.

This technique is employed to store and preserve cells, tissues, and organs for transplantation, research, or future use.

Contact Us

Ultra low temperature freezers are vital tools in various scientific, medical, and industrial settings, providing the ability to maintain samples and products at very low temperatures. By creating a stable and controlled environment, these freezers ensure the long-term preservation of valuable biological materials, pharmaceuticals, and other critical substances.

The continuous advancements in technology have made ultra low temperature freezers more efficient, reliable, and feature-rich, further enhancing their utility across a broad range of applications. As research and medical discoveries continue to progress, the role of ultra low temperature freezers will undoubtedly remain indispensable in preserving the frontiers of science and human health.

If you’d like to speak to a member of our team regarding our ultra low temperature freezers, or would like more information on how they work, please call 0161 772 5666, or email info@coolmed.co.uk.  A member of our team will be happy to help!