Silk worms are eating graphene in order to make wearables more wearable.
A group of scientists have presented work looking at silk to create a more flexible generation of body sensors that will monitor functions, including exertion, in real-time.
“There is a whole world of possibilities for silk sensors at the moment. Silk is the ideal material for fabricating sensors that are worn on the body,” Dr. Yingying Zhang said in a statement. “One possibility we foresee is for them to be used as an integrated wireless system that would allow doctors to more easily monitor patients remotely so that they can respond to their medical needs more rapidly than ever before.”
Even though body sensors are capable of monitoring human health, they still have limitations. For example, strain sensors, which evaluate changes in force, can’t be stretchable and sensitive at the same time as is necessary for conductivity. Silk on the other hand, which is stronger than steel and more flexible than nylon, could help solve that problem. One drawback of silk, however, is that it doesn’t conduct electricity well. To remedy this challenge, Dr. Zhang’s team at Tsinghua University in China is working on a new experiment to boost silk’s conductivity, so they can be successfully used in body sensors.
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The group decided to test two different strategies—one involving temperature alteration and another involving feeding silkworms graphene.
In one approach, the group treated silk in an inert gas environment, where temperatures varied from 1,112 degrees to 5,432 degrees Fahrenheit. Due to this temperature change, the silk became soaked with conductive graphitized particles. With this approach, the group created pressure sensors, strain sensors sand a dual-mode sensor capable of evaluating pressure and temperature at the same time.
For the other method, the group fed carbon nanotubes or graphene to silkworms. Only some of the nanoparticles were naturally incorporated into the worms’ silk, demonstrating that more testing still needs to be done for conductivity. The group is still experimenting with this method in hopes of producing electrically conductive fibers in coming years.
Based on these results, Dr. Zhang would like to develop an integrated set of silk-based, self-sufficient body sensors that would be powered by nano-generators. Dr. Zhang also suggested that the silk sensors could even be used to create more realistic robots that can sense physical changes and distinguish between people’s voices. With funding from the National Natural Science Foundation of China and Key Technologies Basic Research and Development Program, the team of researchers could develop a more advanced and sustainable solution for body sensors and wearable technology.