Spiders Spin Super Silk After Being Spritzed with Graphene
Researchers speculate that the spiders incorporated the solution into their silk as they spun their webs.
Image: Vincent Lock/Flickr
Spiders spritzed with a carbon nanotubes or graphene particle solution were discovered by researchers in Italy to produce a stronger than usual super silk, opening up the possibility of some kickass materials hitting the market in the future.
Graphene is widely touted as one of the world's strongest artificial materials, and is made of sheets of carbon, which are just one atom thick. In the organic world, spider's silk—which has been perfected over 400 million years of evolution—is like its natural equivalent. So Pugno decided to see what would happen when he mashed both together.
"I was aiming to produce even stronger and tougher silk," lead author of a recently published study and material scientist, Nicola Pugno, told me over the phone.
With a hardy team of researchers, Pugno took five spiders from the Pholcidae family and spritzed them a water and graphene particles (200 to 300 nanometres wide) solution. A further ten spiders were sprayed with carbon nanotube and water solution so that results could be compared.
The researchers found that while some spiders produced poorer quality silk than usual, others produced an enhanced super silk. According to a report by New Scientist, a spider doused with a nanotube solution produced the best fibres, which were 3.5 times as tough and strong as the silk spun by Orb spiders.
The research could eventually result in the production of a range of "bionic materials"
The experiment, however, was also not without its fatalities, with the team losing a couple of arachnids along the way. A question that also remains to be answered, is how exactly these spiders incorporated the super-strengthening solution into their silk. Pugno explained that he and his team didn't follow this procedure, but that he personally thought that the solution was incorporated directly into the silk as the spiders spun their webs.
"We have no direct evidence of this, but as the carbon nanotube or graphene is within the bulk of the silk and not just coating the surface, I suspect that it was incorporated during the spinning," said Pugno, while adding that this was more of an opinion, but the most plausible scenario so far.
In terms of applications, though hypothetical uses such as super strong net catching a falling aircraft have been suggested, Pugno told me that this wasn't the best example. "You could use this for extreme textiles," he told me. Extreme textiles, according to Pugno, are materials that are strong and tough, and which possess a multi-functionality that allows them to change properties and become conductive, for example.
"You could use this for when you need materials with superior characteristics," said Pugno, giving robust clothes as an example. While graphene has been widely dubbed as a "wonder material" that could help produce bullet proof armour, Pugno explained that super strength silk would not be so great for ballistic protection, unless it was combined with another material.
Up next, Pugno and co. want to apply this experiment to silkworms. But he tells me that at the moment, this is all a "proof of concept" which has possibly opened up a new research field, which could result in the production of a range of "bionic materials." "Today a lot of things are limited by their intrinsic material strength, but we can push this limit a bit," he added.