Laboratory freezers and refrigerators: how can samples be preserved throughout the cold chain?

From a straightforward 2–8 °C laboratory refrigerator to an -80 °C ultra-low temperature freezer, and even -150 °C cryogenic solutions, the cold chain underpins analysis quality, regulatory compliance and the long-term integrity of sample collections. These units combine temperature stability, uniformity, rapid recovery time after door opening and traceability (alarms, data logging). Choosing the right model means matching temperature range, usable capacity, energy consumption, noise level and accessories (racks, monitoring, CO?/LN2 back-up) to your workflow.

What are the different types of laboratory freezers and refrigerators?

The laboratory cold chain spans several categories: refrigerator (2–8 °C) for sensitive reagents, -20 °C freezer for day-to-day use, -30/-40 °C for extended storage, ULT -80 °C for biobanks, and -150 °C solutions as a partial alternative to liquid nitrogen. Combined fridge/freezer versions optimise the footprint, while cold options (alarms, back-up, data logging) and racks keep inventories organised.

On the technology side you’ll find single-stage compressors (2–8 °C, -20 °C), compressor cascades for -80 °C and -150 °C, high-performance insulation (foam, vacuum-insulated panels), heated anti-frost gaskets and natural refrigerants (R290, R600a) to cut the carbon footprint. ULT units favour manual defrost for temperature stability. Key selection criteria include:
• Range/Uniformity (±0.1 to ±3 °C by category), warm-up and recovery times.
• Volume and format (upright cabinet for rapid access, chest for better holdover when opening).
• Energy (kWh/day), noise level, heat rejection.
• Safety (locking, A/V alarms, dry contact, battery), CO?/LN? back-up for ULT.
• Organisation (stainless/aluminium racks for 2”/3” boxes, trays, dividers), label compatibility and inventory management.

In which sectors and applications are laboratory freezers and refrigerators used?

• Life sciences : storage of antibodies, enzymes, DNA/RNA repositories, cell lines at -80 °C.
• Pharmaceutical/biotech : clinical batches, sample library, intermediate stability studies, GMP standards.
• Food and beverage : control samples, microbiological reference standards, HACCP plans.
• Environment : water, soils, biological tissues prior to analysis, chain of custody.
• Cosmetics : sensitive raw materials, accelerated ageing tests at +5 °C.
• Forensic/clinical : biological control samples, sera, population biobanks.
• R&D : pilot samples, compound libraries, SBS-format plates in dedicated racks.

The available types of laboratory freezers and refrigerators

Frequently asked questions about laboratory freezers and refrigerators

What temperature for long-term nucleic acids?
Favour a ULT at -80 °C for DNA/RNA; -150 °C if the storage window is very long or highly critical.

Frost-free or manual defrost for a ULT?
Manual defrost minimises fluctuations and preserves stability. Frost-free is useful in refrigeration, not recommended for ULTs.

How to cut energy consumption?
Choose natural refrigerants, high-performance insulation, set the temperature only as low as needed, inner doors, and maintain filters/gaskets.

Chest or upright: which to choose?
The chest retains cold air better when opened; the upright offers fast access and vertical rack organisation.

What are 2”/3” racks for?
They streamline the inventory, shorten door-open time and standardise boxes and plates so samples are easy to find.

Do you need CO?/LN2 backup?
Recommended on ULT units to safeguard during failure or extended shutdown. Pair with alarms and remote dry contacts.

What maintenance should be planned?
Clean filters, check gaskets, calibrate probes, periodic defrost, verify alarms and the temperature logger.