Spider Legs Hold the Key to the Ultimate Anti-Adhesive

That spider webs are sticky is common knowledge. Their silk threads can also be tougher than Kevlar. Of course, their goal is to trap prey that is often larger than spiders themselves. However, those sticky fibers can entrap their prey without the spiders getting caught up in their webs. Cribellate spiders, named after the organ that produces this type of silk, have been a frequent object of study. This time, a team of researchers was looking into innovative approaches to handle sticky nanofibers. And that is how they decided to study the technique used by cribellate spiders to produce their silk. Instead of creating a single thread, this type of spiders has a silk-spinning organ that combines several nanometer-thick threads into one. To achieve this, they use a calamistrum structure on their legs that combs the fibers.

Anna-Christin Joel and her team at the RWTH Aachen University wondered what would happen if the calamistrum was shaved from the spider’s legs and if that structure held the key to the anti-adhesive qualities they were researching. Once they carried out the procedure, they confirmed that nanofibers now got stuck to the spider’s legs. So they turned their attention to the calamistrum to uncover its secrets. They found that the surface was covered in nanoripples that prevented the nanofibers from making contact with the comb’s surface.

Next, they replicated these nanostructures by lasering those patterns onto PET foils, which were later coated with gold. Just as they expected, the resulting comb now showed anti-adhesive properties that were almost as efficient as those found in spiders. This innovative technology project is still in development. Still, Joel and the rest of the team believe that it could open the door to the creation of new devices able to handle extremely delicate nanomaterials.

A powerful painkiller from spider venom

As lethal arachnides like the black widow can attest, spiders produce some of the most potent neurotoxic venoms in nature. However, these substances could also be a source of inspiration for a new generation of non-addictive painkillers. Currently, pain treatments are based on opiates, both natural like morphine and synthesized like fentanyl. In her quest to find an alternative, chemical biologist Christina Schroeder set her eyes on a peptide found in the venom of a tarantula called the Chinese Bird spider (Cyriopagopus schmidti). Huwentoxin-IV inhibits the activation of the sodium channels, preventing the flow of sodium ions that trigger pain receptors in the nervous system. While this peptide was already known to the scientific community, Schroeder has found a way of improving its efficiency and enabling the targeting of specific pain receptors. The research is still in an early stage, but Schroeder has already dispelled the idea of spider farms where the insect would be milked for their venom, as the molecule will be synthesized in a lab.      

Source: IFLS, Science Alert