The new tattoo: draw electronics on the skin

One day, people could control their own health conditions simply by lifting a pencil and drawing a bioelectronic device on their skin. In a new study, engineers at the University of Missouri demonstrated that the simple combination of pencils and paper could be used to create devices that could be used to monitor personal health.

Their findings are published in the journal. procedures of the National Academy of Sciences.

Zheng Yan, an assistant professor at the College of Engineering, said that many commercial biomedical devices on the skin often contain two main components: a biomedical monitoring component and a surrounding flexible material, such as plastic, to provide a supporting structure for the component. maintain a skin connection to a person’s body.

“The conventional approach to developing a biomedical electronic device on the skin is often complex and often expensive to produce,” he said. “In contrast, our approach is low cost and very simple. We can make a similar device using widely available pencils and paper.”

Since their invention, pencils, made of lead that include various levels of graphite, clay, and wax, have often been used for writing and drawing. In the study, the researchers found that pencils that contain more than 90% graphite can conduct a large amount of energy created by the friction between paper and pencil caused by drawing or writing. Specifically, the researchers found that 93% graphite pencils were best for creating a variety of bioelectronic devices on the skin drawn on commercial office copy paper. Yan said that a biocompatible spray adhesive could also be applied to the paper to help it better adhere to a person’s skin.

The researchers said their discovery could have broad future applications in personalized home health care, education and remote scientific research, such as during the COVID-19 pandemic. Yan said the group’s next step would be to develop and test the use of biomedical components, including electrophysiological, temperature and biochemical sensors.

“For example, if a person has a sleep problem, we could draw a biomedical device that could help monitor that person’s sleep levels,” he said. “Or in the classroom, a teacher could engage students by incorporating creating a portable device using pencils and paper into a lesson plan. Also, this low-cost, easily customizable approach could allow scientists to conduct research at home like during a pandemic. “

An added benefit of their approach, Yan said, is that paper can break down in about a week, compared to many commercial devices that contain components that don’t break down easily.