Innovations in ultra-low temperature freezer technology by Thermo Fisher Scientific

Today, the freezer is as commonplace in the laboratory environment as it is in the home, and the need for precise refrigeration has grown considerably over the last few years. High performance, ultra-low temperature (ULT) freezers are an essential piece of equipment in the laboratory, providing long-term protection and storage for valuable biological samples on a daily basis in industrial, clinical and research applications worldwide. Therefore, protecting the integrity of samples is extremely important and can be achieved by combining rapid temperature recovery, temperature stability, and operational efficiency, all in a productive and comfortable lab environment.

However, for lab applications, not just any freezer will do and choosing the wrong one can be costly. A freezer door that is opened frequently or kept open for extended periods of time could expose your samples to warm ambient air, creating an opportunity for decreased sample integrity. In addition, many lab professionals do not realise the consequences of storing valuable samples and materials, such as DNA, RNA, cells, and protein samples in conventional freezers. These units are not designed to maintain critical storage requirements demanded in most laboratory applications; inadequate systems result in wider temperature fluctuations, as well as uneven temperature distribution throughout the cabinet. Choosing a freezer that provides tight temperature uniformity and delivers rapid temperature recovery is vital in maintaining sample integrity.

Cold storage technologies

ULT freezer technology is now a conventional industrial technology that has recently achieved a high level of maturity worldwide due to the increased levels of laboratory protocol regulations. Minimal fluctuations in temperature are critical to the viability and effectiveness of biomedical products so international regulatory bodies require laboratories to constantly monitor the temperature variation during the storage process. There is also a need for the cooling industry to develop cost-effective and environmentally sustainable solutions to increase energy efficiency. This means focusing on technologies, materials, and solutions that enable new cooling solutions to be delivered in an environmentally responsible manner to enable standards for safety and performance to be met without compromising freezer performance.

Energy-savings or high-performance mode through the touch-screen interface	Construction features include ergonomic door handle and polystyrene-insulated inner doors	Intuitive touch-screen user interface

New innovation in ult freezers

There are ultra-low temperature freezers, and then there are the new series of Thermo Scientific ultra-low temperature freezers.Built specifically to protect the most critical of samples, the new Thermo Scientific -86°C freezers achieve outstanding thermal performance, safety and security through state-of-the-art engineering. These new freezers feature an outstanding BTU (British thermal unit) reserve. This leads to fast door opening recovery times so that sample integrity isn’t compromised. Based on the internal performance data, the freezers can save up to 15 per cent in energy usage when operated in energy-savings mode v/s high-performance mode. For GMP applications, high-performance mode offers ultra-tight temperature uniformity. Both options can be accessed through an easy-to-use, touch-screen interface.

Using a combination of water blown foam insulation with vacuum panel technology, the new freezers maximise sample-to-vial footprint storage, energy and temperature uniformity. Five new capacities are available ranging from 300 cryobox capacity (30,000 2mL vials) up to 700 cryobox capacity (70,000 2mL vials).

One problem with freezing is that it is an exothermic process, and the excess heat needs to be removed in some way in order to maintain controlled cooling. Advanced ULT freezers require, such as the new series of Thermo Scientific -86°C freezers, require less power to efficiently maintain cabinet temperatures which in turn reduces heat emissions into the lab environment. This reduces air conditioning and energy costs, and maximises operational efficiencies. In addition, a water-cooled condenser option is available for these new Thermo Scientific ULT freezers to further reduce energy usage.

Another problem often faced in the lab is the noise levels associated with ULT freezers. Fortunately, the new Thermo Scientific ULT freezers have been constructed with an interior storage compartment that uses advanced noise abatement and super insulation technologies to help minimise noise output. These technological advancements mean that the ULT freezers are now a lot quieter, allowing them to reside directly inside the lab. Having the freezer inside the lab maximises efficiency in regards to sample preparation time and minimises sample exposure to ambient air. Researchers, who spend many hours surrounded by lab equipment, also benefit from a quieter and more productive, efficient, and comfortable working environment. Thermal insulation inside the freezers is achieved using super insulation, a vacuum formed panel consisting of multi-layers of glass fibre. This is encased by a non-gas permeable membrane to insulate the housing, which subsequently reduces freezer wall thickness from traditional foamed in place insulation. This new compact footprint means that storage and laboratory space is no longer taken up because of thick layers of insulation. Tight door seals also prevent warm, moist air from entering the freezer so ice builds up more slowly and less defrosting is needed. This design is also effective in preventing energy from re-entering the freezer, thereby improving energy efficiency and in-turn decreasing heat injection into the surrounding environment.

Information at your fingertips

A new touch-screen user interface provides access to vital freezer information, including event log, settings, user profiles and the ability to store up to 15 years of temperature and event data on its on-board computer.

Importance of wireless monitoring

A mechanical or electrical failure can ruin your precious samples stored inside not just a freezer, but any lab product with a controlled environment. The Thermo Scientific Smart-Vue wireless monitoring solution safeguards the integrity of important laboratory storage by continuously monitoring critical parameters of laboratory equipment and securely logging data. Lab personnel are notified remotely when sample integrity is threatened. This wireless solution features audit trail traceability with conformance to 21 CFR part 11, and other regulatory requirements.

Conclusion

There are several criteria to consider when evaluating the proper laboratory cold storage solution: Temperature stability and recovery; Sample integrity protection; Safety and security; Intelligent user interface ; Energy efficiency. Combining these advances with end user education ensures that, although it is not easy to be green in the laboratory it is at least possible now.

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