Scientists discover "Band-Aid" that senses temperature, delivers medicine to the skin (Video)

Since its introduction in 1920, adhesive bandages have been a staple item in first-aid kits worldwide. Decades later, a team of US researchers have attempted to inject technology in transforming what was known as a simple wound dressing to a “smart” one.

Touted as the Band-aid of the future, a gel-like material has been built with electronics, such as temperature sensor and LED lights. This makes the sticky and stretchy material release medicine whenever there is a change in skin temperature, as well as turn the light indicator depending on the need, such as when the drug level is low.

According to a new study published in the journal Advanced Materials, the “smart wound dressing” is made of hydrogel that can be stretched with flexible body parts, such as the elbow or knee, while still keeping the embedded electronics functional and intact.

The hydrogel is designed by Xuanhe Zhao, an Associate Professor in Massachusetts Institute of Technology’s Department of Mechanical Engineering. Majority of the rubbery material is made up of water, he says. Its adhesive is strong enough to attach to surfaces, such as gold, titanium, aluminum, silicon, glass and ceramic.

Within the hydrogel, the team embedded various electronics, such as conductive wires, semiconductor chips, LED lights and temperature sensors. Zhao says electronics coated in hydrogel may be used not just on the surface of the skin but also inside the body. For example, as implanted, biocompatible glucose sensors, or even soft, compliant neural probes.

“If you want to put electronics in close contact with the human body for applications such as health care monitoring and drug delivery, it is highly desirable to make the electronic devices soft and stretchable to fit the environment of the human body. That’s the motivation for stretchable hydrogel electronics,” Zhao explained.

The versatile matrix possesses a unique capability, according to the researchers. When a sensor senses something different, like an abnormal increase in temperature, the device can release drugs to that specific location and select a specific drug from one of the reservoirs, which can diffuse in the hydrogel matrix for sustained release over time.

In the future, Zhao envisions hydrogel to be an ideal, biocompatible vehicle for delivering electronics inside the body. He is currently exploring hydrogel’s potential as a carrier for glucose sensors as well as neural probes.

Last month, a “smart” medical dressing that changes colour when it detects infection has been developed by a team of scientists at the University of Bath in the UK. It reduces the unnecessary use of antibiotics and helps address the global problem of antibiotic resistance. According to the team, this will enable doctors to quickly identify patients with an infection and prevent them from giving antibiotics to those who don’t need them.