Temperature and Type of Material

Biological material degrades over time. In order to preserve material for future research, it must be stored in a way that slows down this process. The most effective way to do this is to freeze and store at low temperatures. The lower the temperature, the better. It is often said that it cannot be too cold when storing biological material, but storage at very low temperatures is expensive.

The choice of storage temperature will depend on the type of material and any known analytes you wish to study later. In some studies, it is not always known at the start of the project which analytes you want to study and it is therefore advisable to choose a temperature that suits most purposes and possible analyses. Some types of molecules are more easily degraded than others and require different storage conditions than more robust molecules.

You can distinguish between normal freezers (-20 °C), ultra-freezers (-80 °C) and cryo-freezers (<- 136 °C). Many choose to store their research biobanks at -80 ° C. The table below presents the most common temperatures for long-term storage of various sample materials. Note that specimens for special analysis purposes may have their own requirements for the way in which freezing takes place, such as live cells.

Sample type	Storage temperature at long term storage
Urine	- 80 °C
Plasma	- 80 °C / - 196 °C
Full blood	- 80 °C / - 196 °C
DNA	- 20 °C
RNA	- 80 °C
Tissue	- 80 °C (snap freeze in LN₂ first)
Cells	- 196 °C
Feces	- 80 °C
Breast milk	- 20 °C