The dream of an endless life could come true.

Emil Kendziorra thinks so.

"There is still no evidence that it will not be possible to bring cryopreserved people back to life at some point in the future," says the owner of Berlin-based Tomorrow Biostasis GmbH.

In an office near the Spree, he and ten employees look after more than 200 customers who have opted for cryopreservation after death.

The company does not hide the fact that this is just an opportunity.

The service is almost unique in Europe.

"Foreign competition is relatively small in Europe," says Kendziorra.

"There are a few clubs and volunteer associations." Other providers are mainly in the USA.

The two relevant are the Cryonics Institute and the company Alcor.

Tomorrow Biostasis has customers from all over Europe.

The average customer is between 25 and 45 years old.

Many customers have a technical background;

they include consultants, scientists, doctors, computer scientists and engineers.

70 percent are men.

In the long term, Kendziorra expects the industry to grow.

Around 400 people are currently cryopreserved around the world.

No unknown technology

"Cryopreservation is a technique that combines two things: low temperatures and cryopreservatives," explains Kendziorra.

The method should result in the cellular structure of the human body being preserved over a period of several hundred years after its death.

Then one day it could be taken out of cryopreservation again if research progresses.

According to Kendziorra, it is difficult to say whether a customer will still be in his own body when he wakes up or whether parts of him will only be in someone else's body or even in a robot.

The cryopreservation of biological materials is not an unknown technology, says microbiologist Silke Pradella, who works at the Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures GmbH in Braunschweig.

Pradella curates the collection of cyanobacteria and protists.

The cryopreservation of these organisms is part of her daily tasks, she reports.

The renowned institute houses the most diverse collection of biological resources in the world.

"Most of our microorganisms and cell cultures are archived by freezing them alive in liquid nitrogen at ultra-low temperatures of down to minus 196 degrees Celsius and storing them in large tanks," explains Pradella.

"The conditions of cryopreservation are controlled in such a way that the microbes not only survive freezing but also thawing and can restore their normal cell activity." And with success, albeit with losses.

"The success rate of cryopreservation for our cyanobacteria cultures is around 85 percent." It must be prevented that ice crystals form during freezing or thawing and uncontrolled osmotic effects occur, which then destroy the cellular structure.

"That's why you add antifreeze when you freeze it.

This works with the microorganisms because of their small size, since the antifreeze can penetrate the cells quickly and protect them.”

Two improbabilities

The organisms are first cooled to minus 80 degrees.

Then they end up in liquid nitrogen.

Looking at Kendziorra's idea, Pradella sees two improbabilities: first, bringing a dead body back to life, and second, overcoming the hurdles of cryopreservation.

Pradella believes that the project is highly unlikely to succeed.