For some of us, especially those of us who already comb some gray hair, talking about paper and pencil generates a huge succession of childhood memories. It takes us back to other times that I’m not saying were better or worse, I’m just saying that they were different, especially for us, that we were younger. In any case, talking about such a combination makes me think about taking notes and solving exercises in class, about killing off hours by scribbling, writing down addresses and phone numbers of new friends … What it doesn’t make me think of at all is science. And even less in medicine.
Fortunately, there are people who are much more open-minded than I am, and I include the University of Missouri team of researchers who just published a paper in which they bring the set of paper and pencil to a surprising and fascinating use: use them together as part of a biometric system effective and economical.
The key is that graphite “has” energy, we must remember that it is one of many forms that carbon has, and that, in addition, can function as a sensor electrode. And at the same time, the paper provides a flexible support structure for the signal collected by it. In other words, if you pick up paper and pencil (the mine must have a minimum of 90% graphite), you will have created a conductive structure that, thanks to the flexibility of the paper, can adapt to practically any surface. In this way, the combination of paper and pencil can be used to measure certain constants.
This investigation opens the field to the development of all kinds of wearables able to monitor in real time things like body temperature or glucose level. In this regard, the tests carried out by the researchers have shown that the results obtained by the biometric sensors made with paper and pencil are very reliable and, therefore, could be used as alternatives to the current versions of them.
Paper and pencil are made up of cheap and easy-to-obtain materials, in addition to not causing problems such as those associated with plastic, a common component today in this type of sensor. And although in both cases the sensors degrade quickly, the same does not happen with the materials used for their manufacture. It is only necessary to remember the low biodegradability of the plastic and, therefore, the need to establish recycling systems for it, to prevent monstrosities such as the garbage island or, to be more exact, the growing number of them that have been detected in recent years.