Sun exposure becomes personal with portable UV sensors

RMIT researchers have developed an active UV (ultraviolet) ink that changes color when exposed to different types of UV rays and can be printed and worn as a disposable disposable wristband.

A personal struggle with vitamin D deficiency led Professor Vipul Bansal to develop color change sensors that are available in six variants to reflect the range of human skin tones.

Bansal said this discovery could help provide people with an accurate and simple measure of their personal exposure levels throughout the day.

"We can print our ink on any paper surface to produce inexpensive portable sensors in the form of bracelets, headbands or stickers, for example," he said.

Although humans need some sun exposure to maintain healthy levels of vitamin D, excessive exposure can cause sunburn, skin cancer, blindness, wrinkles and signs of aging. premature.

To understand what a healthy amount is, you have to understand your personal classification, types I to VI, because everyone has very different needs for solar exposure.

Diseases such as lupus and many medications increase the photosensitivity of our skin and reduce our ability to absorb vitamins through diet, which makes monitoring our sun exposure thresholds very individual.

"We are delighted that our UV sensor technology allows the production of custom sensors that can be tailored to the specific needs of a particular individual," said Bansal.

"The low-cost, child-friendly design of these UV sensors will make them easier to use as educational materials to increase awareness of solar safety."

Currently, the only guide to handle sun exposure is the UV index, but this blunt tool only indicates the intensity of UV rays. It does not act as a specific tool to monitor the daily exposure of each individual.

Clear skin (type I) can only tolerate one-fifth of UV exposure that dark skin (type VI) can undergo before damage occurs, while darker types require more than time in the sun to absorb healthy amounts of vitamin D.

The discovery also has applications beyond the health sector, as over time, UV rays can have adverse effects on the lifespan of many industrial and consumer products.

Monitoring this exposure could help improve the safety and reliability of a range of items, including military vehicles and equipment, while achieving huge cost savings.

The document entitled "Dosimetry to the naked eye, specific to skin colors and selective spectroscopy of UVA, B and C radiation" by the member of the Bansal team, Wenyue Zou, Vice Chancellor , was published in Nature Communications (DOI: 10.1038 / s41467-018-06273-3).