Question

Write a short note on cryopreservation.

Answer 1

In the field of biotechnology, various types of biological samples like the cell, tissues, hormones, sperm, oocytes, preimplantation embryos, and some organs are preserved for various purposes in the lab in a systematic and scientific method.

Complete answer:
Cryopreservation is the technique of cooling and preserving various biological samples such as cells, tissues, or organs to maintain their viability. This technology of cooling and storing biological samples or cells is done in a deep freeze at sub-zero temperatures for preservation. The sample is commonly kept below the freezing point of approx. $- {196^ \circ }C$. At this temperature, all the activities of the samples stop and lead the cell to die. This temperature permits high rates of survivability of the cells upon thawing.
Biological materials such as cells, oocytes, spermatozoa, tissues, ovarian tissues, pre-implantation embryos, organs, etc. are preserved in this technique and kept in extremely cold temperatures without affecting the cell’s viability. Dry Ice and liquid nitrogen are also used in this method.
Cryopreservation is passed through a number of steps. At the time of selecting samples volume, density, pH, morphology and some few important criteria should be checked. Then various Cryoprotective agents such as glycerol, FBS, salts, sugars, glycols are added to the samples. These factors help in decreasing the freezing point of the medium and cooling rate so that crystallization of the sample does not occur. After that, the samples are kept at an extremely low temperature in the freeze for at least five to twenty-four hours to protect cells from damage and cell death. And finally, the process of thawing is done where the rate of cooling is controlled.
There are several benefits of using the cryopreservation technique such as fertility treatments, safety from genetic contamination, providing safeguards the genetic integrity of valuable stains, preservation of the germplasm of endangered species, storing cells, and other samples for a long time, protecting the samples from disease and microbial contamination.

Note: Cryopreservation is a technology that stores organelles, cells, tissue, or other biological materials by cooling the sample at a very low temperature. To preserve the sample in this way a few criteria such as sample volume, density, pH should be maintained. This process is done for various purposes such as fertility treatments, preventing genetic contamination, protecting the samples from disease and microbial contamination, storing samples for a long period, etc.