An international research group has devised an ink-jet printing technique for producing temporary tattoo electrodes that can be used for long-term monitoring of electrical impulses from the heart and other muscles.
The team included scientists from the Italian organisations Instituto Italiano di Tecnologia (IIT) Pontedera, Università degli Studi and Scuola Superiore Sant’ Anna, and Graz University of Technology (TU Graz) in Austria.
Standard diagnostic approaches such as electrocardiogram (ECG) and electromyography (EMG) use gel electrodes to transmit the impulses.
However, such electrodes are stiff, limit patient mobility and cannot be used for long-term purposes as the gel dries out over a short duration.
To address these concerns, the team printed conducting polymers on commercial temporary tattoo paper and directly integrated external connections required for signal transmission.
The tattoos can be applied to the skin and their thin structure allows attachment to uneven body parts.
TU Graz Institute of Solid State Physics materials scientist Francesco Greco said: “With this method, we have managed to take a big step forward in further developing epidermal electronics.
“We are on a direct road to making an extremely economical and simple as well as versatile applicable system which has enormous market potential.”
Greco added that international biomedical companies have already started showing interest in joint creating marketable products.
In order to avoid any inaccuracies, the researchers have designed the tattoo electrode in such a way that it will retain its conductivity even during perforation caused because of hair growth.
When tested for three days, the electrodes were observed to have continuously measured electrophysiological signals of patients and athletes without affecting their normal activities.
The researchers say that the tattoos can be printed in various sizes and arrangements, and they are working towards devising wireless tattoo electrodes with an integrated transistor to facilitate targeted stimulation of body parts.