Scientists from the Massachusetts center for the application of technology in medicine (MGH-CEM) has developed a simple method of maintaining of water and solutions on the basis of water in the liquid state at temperatures much smaller the usual “freezing point” for a very long periods of time. While they managed to do it with the volume only a few ounces, their approach, described in Nature Communications, may one day provide a safe prolonged preservation of blood cells, tissues and organs, and to improve the safety of food.
“Water and other aqueous solutions in the amounts that we meet every day, usually freeze when cooled below the freezing point of 0 degrees Celsius,” says Berk Usta, Ph. D., of MGH-CEM, co-author of the work. “Our approach, which we called “deep hypothermia”, is to cover the surface of a liquid solution which is not miscible with water, like mineral oil, to block the interaction between water and air. This surprisingly simple, practical and inexpensive approach hypothermia liquids for long periods can discover many methods to preserve food and medicine and will enable conduction of fundamental experiments that were not previously available.”
Is it possible to freeze organs for a long time?
In most real environments, water and aqueous solutions begin to freeze when the temperature reaches below zero, and ice crystals are randomly generated where the liquid in contact with air or various impurities in the solution. Hypothermia, which helps to maintain the liquid at a low temperature without crystallization, can be carried out only with small volumes and for short periods of time, using equipment with high pressure, which is expensive and can damage tissue or other biological materials.
Lowering the temperature of any biological material in the process, for example, cold storage of perishable products and organs for transplantation – slow metabolic and other reactions. Hypothermia prolongs the slowdown of the metabolism without the damage caused by crystallization of ice. Scientists have discovered that sealing the surface of a small (1 ml) water sample oil based on hydrocarbons such as mineral, olive or paraffin oil, can suppress the formation of ice at temperatures down to -13 degrees during the week. In the experiments with more complex oils, and simple hydrocarbons like alcohols and alkanes, they managed to keep 1 ml of water samples and suspensions of cells supercooled to -20 degrees for 100 days and 100 ml samples for a week.