The long-term storage of cattle sperm, cells, etc. is indispensable without the cryogenic container liquid nitrogen tank!
The container alone is not enough. To preserve the sample for a long time without damaging the activity, a liquid nitrogen sample storage tank with a suitable caliber and capacity must be equipped with liquid nitrogen. What is important is that regular liquid nitrogen replenishment is indispensable. Because only when the liquid level is properly controlled, the liquid nitrogen tank can truly take advantage of the advantages of vacuum insulation and maintain the long-term activity of cattle sperm, cells, etc.
It is only appropriate to use the height of the sample as a reference!
Common samples such as bovine semen and cells are often fixed in storage tanks using different accessories. For example, bovine semen is a round bucket, and cells are a square bucket, that is, a freezing rack. Without the handle part, they are truly The height at which the sample is placed also varies.
If the height of the sample is not used as a reference and is fixed at a certain value, it is likely that the barrel of the round bucket with a total height of 120mm can be completely covered by liquid nitrogen, and the sample storage temperature is stable. On the other hand, if the rack is taller and has 6 layers, 1-2 layers of cells cannot be completely covered by liquid nitrogen, which may cause temperature fluctuations to affect activity.
Moreover, as liquid nitrogen naturally evaporates, the liquid level in the liquid nitrogen sample storage tank drops, and cell safety will be “threatened.”
Using the sample height as a reference is different. When filling liquid nitrogen, no matter what the accessory is, just look at where the sample is. The initial liquid replenishment is to the neck tube position. When the liquid nitrogen is close to the sample height, inject liquid nitrogen again and firmly Just control the liquid level above the sample.
Now, everyone knows the appropriate level at which the liquid nitrogen sample storage tank should be controlled!