Student researchers at Texas A&M University have developed a 3D-printed electronic skin that can bend, stretch and feel like human skin, opening the door to new advances in human-machine interaction.
Human skin, the brain’s largest sensory organ with more than 1,000 nerve endings, is difficult to replicate. Research at Texas A&M University, led by Dr. Akhilesh Gaharwar, professor and research director of the Department of Biomedical Engineering, focused on replicating these complex properties.
“The ability to replicate the sense of touch and integrate it into various technologies opens up new possibilities for human-machine interaction and advanced sensory experiences,” said Dr. Akhilesh Gaharwar, professor and director of research for the Department of Biomedical Engineering. “It can potentially revolutionize industries and improve the quality of life for individuals with disabilities.”
The team used nanoengineered hydrogels that have electronic and thermal biosensing capabilities. These hydrogels allow the e-skin to form complex 2D and 3D electronic structures during the 3D printing process, an essential aspect of replicating the multi-layered nature of human skin. The research, published in Advanced Functional Materials, was developed in Gaharwar’s lab, with Drs. Kaivalya Deo and Shounak Roy as lead authors of the study.
“The inspiration behind developing E-skin is rooted in the desire to create more advanced and versatile interfaces between technology, the human body and the environment,” Gaharwar said. “The most exciting aspect of this research is its potential applications in robotics, prosthetics, wearable technology, sports and fitness, security systems and entertainment devices.”
One of the main challenges in creating e-skin is developing durable materials that simultaneously mimic the flexibility of human skin, incorporate bioelectrical sensing properties and are suitable for wearable or implantable devices.
“In the past, the stiffness of these systems was too high for our body tissues, preventing signal transduction and creating mechanical mismatch at the biotic-abiotic interface,” Deo said. “We introduced a ‘triple-crosslinking’ strategy to the hydrogel-based system, which allowed us to address one of the key limitations in the field of flexible bioelectronics.”
By adopting a ‘triple-crosslinking’ strategy in the hydrogel-based system, they were able to address one of the key limitations in the field of flexible bioelectronics.
“The most exciting aspect of this research is its potential applications in robotics, prosthetics, wearable technology, sports and fitness, security systems and entertainment devices”, said Dr. Akhilesh Gaharwar.
The researchers also utilized “atomic defects” in molybdenum disulfide nanoassemblies, a material with imperfections in its atomic structure that enables high electrical conductivity, and polydopamine nanoparticles to help the E-skin adhere to moist tissue.
“These specially designed molybdenum disulfide nanoparticles acted as crosslinkers to form the hydrogel and imparted electrical and thermal conductivity to the E-skin; we are the first to report using this as the key component,” Roy said. “The material’s ability for adhesion to wet tissues is particularly crucial for potential healthcare applications where the E-skin needs to conform and adhere to dynamic, moist biological surfaces.”
The study, supported by the National Institute of Health, the Department of Defense and the United States-India Educational Foundation, highlights promising applications for e-skin, including wearable health devices that continuously monitor vital signs such as movement, temperature, heart rate and blood pressure. This technology could bring revolutionary changes not only to industry, but also to improving the quality of life for people with disabilities.