- A team of engineers created a biomedical monitoring device from pencil and paper
- It provides a cost-effective alternative to costly, non-disposable monitoring systems
- One can read temperature, heart rates, uric acid and glucose levels with this device
Engineers from the University of Missouri have found a cheap and effective way of monitoring the human body – using pencil and paper.
Publishing their results in PNAS, they created a method whereby graphite patterns drawn on paper can be placed on human skin to monitor biophysical data.
Traditionally, electronic monitoring equipment is expensive to make due to costly materials with complicated manufacturing processes, and disposing of it when it's reached the end of its life cycle isn't environmentally friendly.
Inexpensive and eco-friendly
These pencil–paper-based-on-skin electronic devices are inexpensive to produce, making it a potential lifesaver for areas with limited resources.
"By using widely accessible pencils and paper as tools, we have developed a variety of cost-effective and disposable on-skin electronic devices, ranging from biophysical sensors and sweat biochemical sensors to thermal stimulators, humidity energy harvesters, and transdermal drug-delivery systems," write the authors.
The patterns are conductive and act as sensing electrodes, while the office copy paper works as a substrate – a layer that supports the graphite – which is stuck onto the skin with a safe adhesive spray. Compared with traditional methods, the quality of recorded signals was the same in pencil-paper devices.
One day, people could monitor their own health conditions by simply picking up a pencil and drawing a bioelectronic device on their skin. (Image: University of Missouri)
Some of the data these devices can pick up include skin temperature, electrocardiograms, electromyograms, alpha, beta, and theta rhythms, heart rates, respiratory rates, sweat pH, uric acid, and glucose.
They also found that pencils containing 93% graphite work the best.
This new method has various applications even for at-home care and education, which will be further investigated by the engineers.
“For example, if a person has a sleep issue, we could draw a biomedical device that could help monitor that person’s sleep levels,” assistant professor Zheng Yan, who co-wrote the paper, told Mizzou News.
“Or in the classroom, a teacher could engage students by incorporating the creation of a wearable device using pencils and paper into a lesson plan. Furthermore, this low-cost, easily customisable approach could allow scientists to conduct research at home, such as during a pandemic.”