Japanese scientists have developed a hypoallergenic electronic sensor that can be worn on the skin to monitor a person's health continuously over a long period.

The wearable device, that can be worn for a week without discomfort, has elastic electrodes, made up of breathable nanoscale meshes, that lets the skin breathe, preventing inflammation.The electrodes contains a water-soluble polymer, polyvinyl alcohol (PVA), and a gold layer -- materials considered safe and biologically compatible with the body."We learned that devices that can be worn for a week or longer for continuous monitoring were needed for practical use in medical and sports applications," said Takao Someya, Professor at the University of Tokyo.

The device can be applied by spraying a tiny amount of water, which dissolves the PVA nanofibers and allows it to stick easily to the skin.It gets conformed seamlessly to curvilinear surfaces of human skin, such as sweat pores and the ridges of an index finger's fingerprint pattern.In addition to nursing care and medical application the new device promises to enable continuous, precise monitoring of athletes' physiological signals and bodily motion without impeding their training or performance.For the study, detailed in the journal Nature Nanotechnology, the team conducted a skin patch test on 20 subjects and detected no inflammation on the participant's skin after they had worn the device for a week.Furthermore, the device's mechanical durability was proved through the repeated bending and stretching, exceeding 10,000 times, of a conductor attached on the forefinger.Its readings of the electrical activity of muscles were comparable to those obtained through conventional gel electrodes, the researchers said."It will become possible to monitor patients' vital signs without causing any stress or discomfort," Someya noted.