Lee Cronin, a scientist at the University of Glasgow, has created cells made of metal that he believes are capable of replicating organic life.
“I am 100 per cent positive that we can get evolution to work outside organic biology,” Cronin tells New Scientist.
In pursuit of his dream, Cronin and his colleagues have crafted microscopic bubbles that they have dubbed “iCHELLs.” New Scientist explains:
His building blocks are large “polyoxometalates” made of a range of metal atoms – most recently tungsten – linked to oxygen and phosphorus. By simply mixing them in solution, he can get them to self-assemble into cell-like spheres.
Cronin and his team begin by creating salts from negatively charged ions of the large metal oxides bound to a small positively charged ion such as hydrogen or sodium. A solution of this salt is squirted into another salt solution made of large, positively charged organic ions bound to small negative ones.
When the two salts meet, they swap parts and the large metal oxides end up partnered with the large organic ions. The new salt is insoluble in water: it precipitates as a shell around the injected solution.
Once created, Cronin claims that he can force the resulting iCHELL to mimic various features of actual organic cells by slightly altering their “metal oxide backbone.” For instance, he can build a porous membrane by creating “an oxide with a hole as part of its structure,” or imbue the iCHELL with a capacity for photosynthesis by adding light-sensitive dyes and a membrane that can separate hydrogen and oxygen.
Taking a page from Charles Darwin’s Thunderdome, Cronin’s team plans to spend the next seven months dividing up a huge batch of mass-produced iCHELLs, and exposing them to various chemical elements. The goal, he claims, is to cull the weak iCHELLs, leaving only the strongest, fittest examples of metallic life.
“If the pH is too low and they dissolve then those droplets will have died,” Cronin says. “I think we have just shown the first droplets that can evolve.”
If this all sounds like a plot to breed a race of unstoppable metal supermen, don’t worry; Cronin’s initial plans seem much more benign (if no less geeky). “There is every possibility that there are life forms out there which aren’t based on carbon,” he says.
Yes Virginia, this entire thing is a proof of concept test for freaky aliens. The unstoppable metal supermen will just have to wait.