The cryotube is a vessel used for storing frozen cells. Its alternate names include "freezer-tube", "Hawking chamber," "freezer-doodle," and "cryo-thingie." The cryotube appears in several Star Trek episodes, and may have undergone refurbishment in the year 3011. 

Impact of nonlinear cooling profiles on cryotube freezing

The impact of nonlinear cooling profiles on the freezing of cell-free alginate beads is examined in this study. The authors note that the results show a strong dependence on ice nucleation temperature, with recovery rates of less than 40% at -12degC and over 90% at -8degC.

In the present study, the influence of nonlinear cooling profiles on cryopreservation was studied by the authors of several papers. While many studies analyzed the freezing process of mammalian embryos and semen, there are fewer studies about the preservation of semen from fish and avian species. This study supports the prediction that a nonlinear cooling profile will provide better results than a linear freezing programme.

Effects of ice nucleation on cell dehydration

Induced ice nucleation results in a honeycomb-like structure with a uniform fine ice crystal structure. Fig. 4B shows ice-nucleated ELS surrounded by clusters of cell cytoplasm. The cells' outlines are discernible at higher magnification, but the cells' intracellular organelles were obscured by the pattern of ice formation.

The rate of ice nucleation was controlled by adjusting the cooling rate after ice nucleation. The rate of cooling was set to a slow pace, so that cells did not become injured. As the ice nucleation process was controlled by the freeze temperature, viable cell numbers were obtained. The rate of protein secretion was also observed, ranging from 10.5 to 1.7 mg/24 h.

The temperature at which the ice nucleation process occurred affected the attachment of endothelial cells to the cryotube. The attachment of endothelial cells was lower without Snomax and higher with 50 mM of 3-OMG. Overall, the effect of ice nucleation on cell dehydration after cryotube freezing was similar in both experiments.

Effects of slower warming on cell numbers and function

The authors evaluated the effect of slow versus rapid warming on cell numbers and function after cryotube freezing.  These findings highlight the need for rapid warming. This study was performed using the Cytell Cell Imaging System. You can read the full paper at: Effects of slow warming on cell numbers and function after cryotube freezing

The optimal freezing protocol involves reducing the temperature to lower the viability of the cells. The temperature must be kept below -80°C. The lower the temperature, the lower the viable cell number. For this reason, slow warming is better for small volume experiments. The authors also note that the faster warming protocol is as effective as a multi-step protocol for large volumes. 

Storage of cryotubes

The process of cryogenic freezing involves preserving biomaterials at extremely low temperatures. These temperatures are typically -150deg C or -238deg F. The method was developed from cryogenics science, which focuses on creating very cold environments and studying the effects of extreme low temperatures. However, there are certain considerations to make when storing cryotube freezing. Here are a few of them.

A proper thawing environment is essential to maintain a high percentage of viable cells. It is best to freeze cells no more than 2% of their volume. It is important to note that the liquid nitrogen level may expand after freezing, so it is important to allow some space for growth. After thawing, it is important to check the cell number in order to determine whether they were preserved correctly. Once the samples are successfully stored, they must be counted.

For cryogenic storage, it is necessary to wrap the vial in a protective film.Moreover, this type of protective wrap helps reduce the risk of biohazards and protects the staff from chemical splash. It is also essential to label storage vials correctly in order to optimize the retrieval process. Choosing cryotubes that have an easy-to-read label helps maximize retrieval time and minimize temperature fluctuations.