Medical tattoo stickers in the future?

Researchers from the University of Missouri say the two materials, which produce energy when used together, could be the basis for various biomedical sensors that stick onto your skin to monitor personal health.

The study was published Monday in the journal Proceedings of the National Academy of Sciences.

“The conventional approach for developing an on-skin biomedical electronic device is usually complex and often expensive to produce,” Zheng Yan, study author and assistant professor at the University of Missouri College of Engineering, said in a news release. “In contrast, our approach is low-cost and very simple. We can make a similar device using widely available pencils and paper.”

Pencils are made of lead that include varying levels of graphite, clay and wax, but an abundance of one of those ingredients together with a piece of copy paper can actually produce energy, the researchers said.

The team found that pencils with more than 90% graphite are able to conduct “a high amount of energy” from friction between the paper and pencil during writing or drawing, the news release said; pencils with 93% graphite proved to be a better electrical conductor.

With help from a spray-on adhesive, people can attach the paper with pencil-drawn electrodes, for example, onto their skin to one day measure personal health such as skin temperature, heart rate and glucose levels.

“For example, if a person has a sleep issue, we could draw a biomedical device that could help monitor that person’s sleep levels,” Yan said. “Or in the classroom, a teacher could engage students by incorporating the creation of a wearable device using pencils and paper in a lesson plan.”