cryopreservationin

Cryopreservation is a technique used to preserve biological material at ultra-low temperatures, typically to halt metabolic activity and extend viability for future use. By cooling to temperatures such as -80°C or -196°C in liquid nitrogen, cells and tissues can be stored for years or decades with the possibility of revival.

Two main approaches govern cryopreservation: slow-freezing and vitrification. Slow-freezing gradually lowers temperature while controlling ice formation, often using moderate concentrations of cryoprotectants to reduce intracellular ice. Vitrification uses very rapid cooling with higher concentrations of cryoprotectants to prevent ice crystal formation entirely, producing a glass-like solid that can improve survival for some cell types.

Cryoprotectants are chemicals that protect biological material from freezing damage but can be toxic at high concentrations. Common agents include dimethyl sulfoxide (DMSO), glycerol, ethylene glycol, and sugars such as trehalose. The choice and concentration of cryoprotectants depend on the material being preserved and the chosen cooling method.

Applications of cryopreservation span reproductive medicine (sperm, oocytes, embryos), stem cell and tissue banking (hematopoietic stem cells, other progenitors, organoids), and biobanking for research and conservation. It is also used for preserving plant germplasm and certain animal genetic resources.

Storage and handling involve cryogenic dewars and careful inventory management, ensuring continuous supply of liquid nitrogen and redundancy in storage facilities. Post-thaw viability depends on material type and protocol, and cryoinjury or osmotic stress can affect function after recovery.

Note: The term “cryopreservationin” is not standard; the established term is cryopreservation. This article describes the widely used concept and methods under that name.