Second skin ... the ultra-thin electronic device that can be applied to skin like a temporary tattoo. Second skin ... the ultra-thin electronic device that can be applied to skin like a temporary tattoo. Photo: John A. Rogers
THE days of connecting patients to medical monitoring machines with bulky electrodes and intrusive wires may soon be over thanks to an ultra-thin electronic device that can be applied to skin like a temporary tattoo.
The stick-on device can measure a person's heart beat, brain waves and muscle activity and, in future, could also be used for wound healing and muscle rehabilitation.
An engineer and co-inventor of the device, John Rogers, said the aim was to develop an electronic technology that could integrate with the skin and was almost unnoticeable to the user.
"[We wanted to] blur the distinction between electronics and biological tissues in ways that can provide new functionality in health-care and non-health-care-related applications," said Dr Rogers , an engineering professor at the University of Illinois.
The device can power a range of electronic components, including miniature sensors, such as EEG and EMG monitors that measure brain waves and muscle activity, and LED indicator lights and semi-conductors.
The "spider's web" of micro-electronics is then embedded into a transparent film that can be laminated on the skin with water. The patch was thin and compliant enough to conform to the surface of the skin without requiring an adhesive, Dr Rogers said.
The membrane was non-invasive, so the researchers hoped it could be used to monitor premature babies and people with sleep apnoea.
Existing technologies measured a person's vital signs using bulky electrodes that might require adhesive tapes and conducting gels or needles, connected to circuit boards and power supplies.
Studies on animals had also shown the device could stimulate muscle contractions, which may allow the device to be used in rehabilitation.
"The key thing about the device is it doesn't constrain the movement of the muscle," Dr Rogers said. His findings were published in the journal Science .
The gadget's negligible width also overcame the rigidity often associated with traditional electronics. "If you make anything thin enough, it becomes flexible," he said.
It can be powered by wireless energy transfer or silicon solar cells and it may be integrated with batteries in the future.
The patch can be applied to most areas of the skin and can remain attached to the skin for one to two weeks.
"The devices we have now – we envision them as things you stick on your skin, wear them for a week, peel it off and reapply a new one," Dr Rogers said.