A "Bank" of donated organs ready for use is on the anvil, for scientists have successfully froze, thawed and transplanted a pig's liver-paving the way for similar transplantation in humans.

It is believed that if human livers, which are about the same size, will be able to survive this process, the new method could actually prove to be a boon to the many people who are in dire need of transplants.

Many of the donated livers, when kept for a longer time, deteriorate rapidly without a blood supply within 12 to 24 hours. Thus it gets difficult to bring them to recipients on time.

According to study leader, Amir Arav, at the Israeli Agricultural Research Organization in Bet-Dagan, the key to limiting cell damage during freezing is to cool the liver very slowly, as this prevents the formation of jagged ice crystals.

In fact, there exist some frog species, which employ a similar technique when they allow parts of their bodies to freeze during hibernation.

"We didn't invent this process, nature did. Some frog species employ a similar technique when they allow parts of their bodies to freeze during hibernation," New scientist quoted Arav, as saying.

For their study, the researchers flushed the blood from the pig's liver, cooled it, and finally encased it in a pair of hollow brass cooling blocks attached to a supply of liquid nitrogen.