Cryobiology is the study of living organisms, organs, biological tissues or biological cells at low temperatures. This knowledge is practically applied in three fields: cryonics, cryopreservation and cryosurgery.

Cryobiology history can be traced back to antiquity. As early as in 2500 BC low temperatures were used in Egypt in medicine. The use of cold was recommended by Hippocrates to stop bleeding and swelling. With the emergence of modern science, Robert Boyle studied the effects of low temperatures on animals.

In 1949 sperm was cryopreserved for the first time by a team of scientists led by S. Polge. This led to a much wider use of cryopreservation today, with many organs, tissues and cells routinely stored in low temperatures. Organs such as hearts are usually stored and transported in low temperatures for transplantation. Human sperm, eggs and embryos are stored in liquid nitrogen in fertility research and treatments. Many people were born from frozen sperm and eggs and in early 2000s a person was born from frozen egg impregnated by a frozen sperm.

Cryosurgery was carried out by James Arnott in 1845 in an operation on a patient with cancer. Although not very widespread, cryosurgery has its benefits. For example, heart surgery on a cold heart (cooled with ice) allows for much longer operations and improves recovery rates for patients.

References

• Why Cryonics?, kuro5hin.org, 24.03.2005