Researchers from the Korea Advanced Institute of Science and Technology (KAIST) in Daejeon, South Korea, have reportedly developed an electronic tattoo ink that can automatically alert people to potential health problems.

The ink is made of liquid metal and carbon nanotubes that work as a bioelectrode, Reuters reported.

According to the researchers, a tattoo drawn with this ink can help monitor heart rates as it creates an electric circuit on the skin.

The tattoo can be connected to an electrocardiogram (ECG) device or other biosensors to monitor a patient’s heart rate as well as other vital signs, such as glucose levels.

This would offer a personalised way for individuals and doctors to monitor individuals’s health conditions.

The researchers developed the non-invasive ink using particles that are based on a soft, silvery metal known as ‘gallium’, which is also used in thermometers and semiconductors.

Platinum-decorated carbon nanotubes used in the ink help conduct electricity and provide durability.

KAIST materials science and engineering professor Steve Park was quoted by the news agency as saying: “In the future, what we hope to do is connect a wireless chip integrated with this ink, so that we can communicate, or we can send signal back and forth between our body to an external device.”

The researchers stated that these external monitors could be located anywhere, including in patients’ houses.

Park continued: “When it is applied to the skin, even with rubbing the tattoo doesn’t come off, which is not possible with just liquid metal.”

In 2018, KAIST researchers developed a new selective nano-photothermal neural stimulation technique to control biological activities remotely.