Dead？ The feasibility of human frozen preservation technology

The idea of preserving the body at low temperatures is to hope that the future of medical technology can revive mankind again, which has always been a scientific illusion, but after many years, human body freezing can really become a way of resurrection?

When a person is declared dead, the body cryopreservation company sends a quick reaction team to dispose of the deceased's body. Once the body enters the freezer, it is cooled to freezing point, and the blood is removed and replaced with a solution that preserves the organ.

The body's blood vessels inject a freeze-protective solution to prevent ice crystals from forming inside organs and tissues, and the bodies are cooled down to 零下130摄氏度 and loaded into a container and stored in a 零下196摄氏度 liquid nitrogen tank.

The latest figures show that about 150 people in the United States store their bodies in liquid nitrogen, with more than 1000 living people planning to save their bodies after death. Human cryopreservation enthusiasts claim to have three reasons to believe in the technology. First, although the tissue needs to wait until the patient is pronounced dead to freeze, they can reduce brain damage by maintaining oxygen levels. Second, cooling the body to a low enough temperature slows the chemical processes in cells and tissues and further prevents the body from degenerating. Finally, although physical damage during the freezing process is unavoidable, they hope that future nanotechnology may repair the damage.

If the body cools to 零下5摄氏度, the water in the cells freezes and forms ice crystals, which can cause severe damage by the membrane. The human freezing facility attempts to overcome this problem through a process called "vitrification" (vitrification). This requires the use of a refrigerant to replace a portion of the body's moisture to reduce the number of ice crystals. So far there is no evidence that we can make human organs glassy. Dayong Gao, a cryogenic biologist at the University of Washington, said: "We can successfully make tiny objects glassy, because the smaller the size, the easier it is to control the cooling and dispersion of the refrigerant." ”

"Even if you succeed in minimizing frozen damage, it is still a problem how to thaw them safely," Dr. Gao said. As a result of thermal stress, the body can easily rupture like glass in the process of heating up. "The resurrection of the human body is probably not at the peak of health, but at the end of life caused by illness or aging." Proponents of human cryopreservation say nanotechnology will one day be able to deliver solutions. No matter how you look at this technology, human freezing is a hope and belief in the future. All of the body's frozen-preservation groups are claiming that, while there is no guarantee that human freezing can work, technology is progressing.