INNOVATION ARTICLES THE IDEA SUBMISSION PORTAL FROM MEDTRONIC

A new form of ‘electronic skin’ promises to bring about significant progress in medical fields from cardiology to neurology.

The ‘skin’, which has also been compared to a ‘temporary tattoo’, is the brainchild of Prof. Yael Hanein from the Micro and Nano Systems Laboratory at Tel Aviv University’s School of Electrical Engineering.

A super-thin film containing electrodes, worn on the skin like a sticker, can sense and record the electrical activity of muscles or nerve cells beneath the skin. The technology used to make this device – screen printing silver and carbon inks onto a soft support patch – is simple, and already extensively used to make flexible electronics from sensors to touch screens in smart phones and computer tablets, but this is the first time researchers have used screen printing to make a robust sensor for monitoring the body’s electrical rhythms.

When using traditional metallic electrodes for electrocardiography (ECG), electromyography (EMG) or electroencephalography (EEG), conducting gel is needed, and there are multiple electric wires, all of which can make the experience time consuming for the clinical practitioner and slightly uncomfortable for the patient. What’s new with Tel Aviv University’s ‘electronic skin’ is that the electrodes require no gel, sticking easily to the skin for long periods without irritation. And the eight electrode sensors, which look like small black dots, are all mounted on one wearable patch, connected to the amplifier with just a single lead. ‘The user doesn’t really feel it and you can move in the most normal, comfortable way for hours,’ explains Prof. Hanein.

Another important plus is that this technology is so user-friendly that technicians won’t be needed anymore - a patient can apply the patch for a heart, muscle or brain activity test on their own at home, and send the recording to their cardiologist or neurologist for analysis.

It’s obvious how this invention could improve the patient experience of having an ECG, EMG or EEG, especially for children. But the range of possible applications is much broader than straightforward ECGs and EEGs: ‘People approach us with new ideas for applications every week,’ says Prof Hanein.

One key area is support for patients with neurological problems where muscles need rehabilitation, from Parkinson’s to stroke recovery to Bell’s Palsy. A patient could use the electrodes to practise the precise muscle movements they need to. ‘Something like this means you don’t have to go to a clinic and practise in front of an expert to get feedback,’ says Prof. Hanein. She adds that this technology could also make early diagnosis easier if patients at risk of Parkinson’s wear the sensors in sleep studies, because strange patterns of electrical activity in RAM sleep can be biomarkers for the onset of motor difficulties.

Of course, all kinds of sleep studies could benefit from this technology. The usual investigations of sleep at a sleep laboratory, Prof. Hanein stresses, can be ‘expensive, and not very comfortable and natural. If you can sleep at home and monitor your sleep without disturbing it, this is very desirable.’

Brain Computer Interfaces are another obvious application, she adds. ‘If you want to transfer information without speech or being able to move limbs, this could be very straightforward with such a technology.’

Screen printing inks to make electrodes can be done on a large scale at very low cost, and uses readily available materials. It’s not yet on the market – Prof. Hanein’s team are working with around 10 different research groups to develop various applications.

Prof. Hanein invented the new electrodes two years ago and since then, development has been rapid. ‘We got very strong confirmation once we started showing it to colleagues,’ she says. ‘Researchers are eager for something that could replace the current technology.’