Health.-They develop an electronic skin with an interesting future in prosthetics, personalized medicine or robotics
MADRID, 30 Nov. 2020 (Europa Press) –
Researchers at the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia have developed a material that mimics human skin in terms of strength, stretchability and sensitivity to collect biological data in real time. This ‘es-kin’ may play an important role in next-generation prosthetics, personalized medicine, soft robotics and artificial intelligence, scientists advance in the journal ‘Science Advances’.
“The ideal electronic skin will mimic the many natural functions of human skin, such as sensing temperature and touch, accurately and in real time,” says KAUST postdoc Yichen Cai.
However, making suitably flexible electronic devices that can perform such delicate tasks while withstanding the bumps and scrapes of everyday life is a challenge, and every material involved must be carefully designed.
Most electronic skins are made by placing an active nanomaterial (the sensor) on an elastic surface that adheres to human skin. However, the connection between these layers is often too weak, which reduces the durability and sensitivity of the material; Instead, if it is too strong, the flexibility becomes limited, making it more likely to crack and break the circuit.
“The landscape of skin electronics continues to change at a spectacular rate – Cai emphasizes -. The advent of 2D sensors has accelerated efforts to integrate these mechanically strong and atomically thin materials into functional and durable artificial leather.”
A team led by Cai and his colleague Jie Shen has created a durable electronic skin using a hydrogel reinforced with silica nanoparticles as a strong and elastic substrate and a 2D MXene titanium carbide as a detection layer, bonded with highly conductive nanowires.
“Hydrogels contain more than 70 percent water, which makes them very compatible with human skin tissues,” Shen explains. By stretching the hydrogel in all directions, applying a layer of nanowires, and then carefully controlling their release, the researchers created conductive pathways to the sensor layer that remained intact even when the material was stretched 28 times its original size.
Its prototype electronic skin could detect objects 8 inches away, respond to stimuli in less than a tenth of a second, and, when used as a pressure sensor, it could distinguish handwriting on it. It continued to perform well after 5,000 warps, recovering in about a quarter of a second each time.
“It is a surprising achievement for an electronic skin to maintain its toughness after repeated use – highlights Shen -, which mimics the elasticity and rapid recovery of human skin.”
Such electronic skins could monitor a variety of biological information, such as changes in blood pressure, which can be detected from vibrations in the arteries to movements of large limbs and joints. This data can be shared and stored in the cloud over Wi-Fi.
“A remaining obstacle to the widespread use of electronic skins lies in the expansion of high-resolution sensors – adds group leader Vincent Tung – however, laser-assisted additive manufacturing offers new promise” .
“We envision a future for this technology beyond biology,” Cai continues. “Stretch sensor tape could one day monitor the structural health of inanimate objects, such as furniture and airplanes.”