The expression “You are what you eat” has taken on a new meaning in the light of the latest research by Japanese scientists from Tohoku University. They were able, without changing the DNA or the way of life of silkworm caterpillars, to teach these insects to produce silk thread with completely different parameters. It's all about a special diet with nanocomponents.
One of the basic difficulties when working with nano-sized elements is that their properties often depend on the location of individual particles in the material, which is extremely difficult to control. In this respect, silkworms turned out to be an ideal "machine", since their biological apparatus in the form of salivary glands forces all the initial components to be located in the emerging thread formed from them in a strictly defined order. As a result, if you add the right ingredients to the caterpillars' feed, you can get a thread with additives that will provide the desired properties.
Among the first, this technology was tested by Chinese scientists who added graphene and carbon nanotubes to the feed of caterpillars. Their Japanese colleagues chose a different path - they took a natural substance cellulose, divided it into nanometer-sized fibers and added to a mixture of crushed mulberry leaves, a favorite food of caterpillars. Analysis of the spun thread showed that the cellulose particles were perfectly aligned in the direction of saliva flow. As a result, the silk thread has become twice as strong while maintaining other properties.