An Australian academic has developed a transparent, wearable sensor patch that can detect UV radiation poisoning and toxic gases, such as nitrogen dioxide.

Dr Madhu Bhaskaran, senior lecturer and co-leader of RMIT University’s Functional Materials and Microsystems research group, has been able to successfully combine brittle oxide materials and rubber platforms to develop the patch.

The primary focus of the research group is to develop functional oxide coatings to create high-performing stretchable devices.

Using zinc oxide applied to a silicone rubber base, they were able to create a harm-free product that is a hundred times thinner than a sheet of paper and is extremely durable.

“The transfer technique [to combine the zinc oxide with the silicone] allows us to use standard microfabrication techniques – which are used to make integrated circuits in silicon industries – while giving us a high yield,” Bhaskaran told IoT Hub.

“The sensors are sensitive to gases (hydrogen and nitrogen dioxide have been tested so far) and UV radiation, retaining their functionality even with stretching of five percent.

“Being a passive sensor and also being transparent and conformal in nature, these sensors could potentially be used as wearable devices on the skin or attached to clothes to monitor exposure to dangerous gases and UV.”

The wearable sensors differ from existing radiation and toxic gas detection systems in that they are able to operate at room temperature, compared to other systems that require heating and therefore, power.

Bhaskaran said the research group was challenged during the material integration process, as functional oxides will only bond at temperatures greater than 250 degrees Celsius, while flexible polymers and plastics disintegrate above 120 degrees Celsius.

She said that they used the naturally weak adhesion of platinum to silicon, allowing them to “create electronics on a rigid substrate such as silicone, and then peel off to transfer onto a flexible substrate”.

Bhaskaran’s work on the sensors allowed her to top the MIT Technology Review’s ‘TR35 Innovators Under 35 Asia’ list, which was announced at the annual MIT Technology Review’s EmTech Asia conference.

Bhaskaran said that the research has garnered significant interest, both here in Australia and in the UK.

“Our devices have only been tested in the lab environment; in order to see such devices in real life we still need to do some engineering, to interface these devices with smart devices such as cell phones,” she said.

She is hopeful a commercial product will be available in the next four to five years.