Krüokaitseaineid

Krüokaitseaineid, also known as cryoprotectants, are substances that protect biological tissues from damage during freezing. They work by reducing the formation of ice crystals and preventing dehydration, which are the primary causes of cellular damage during cryopreservation. Without cryoprotective agents, cells would likely lyse or be irreversibly damaged when frozen.

Commonly used cryoprotective agents include glycerol, dimethyl sulfoxide (DMSO), and ethylene glycol. These molecules are often small and can penetrate cell membranes. They achieve cryoprotection through several mechanisms. Firstly, they increase the solute concentration within the cells and the surrounding extracellular fluid. This lowers the freezing point of water, allowing for slower ice formation and thus smaller ice crystals. Secondly, they can form amorphous (glassy) solids instead of crystalline ice, which is less damaging to cellular structures. Thirdly, they can help stabilize cell membranes and proteins, preventing denaturation and loss of function during cold storage.

The choice of cryoprotective agent and its concentration depends on the type of tissue or cell being preserved, as well as the desired storage temperature and duration. While effective, these agents can also be toxic to cells at higher concentrations or prolonged exposure. Therefore, careful optimization of their use is crucial for successful cryopreservation. Applications range from preserving sperm, eggs, and embryos for fertility treatments to storing cell lines for research and banking organs for transplantation.