Smart plasters can tell if wound is not healing

LONDON - Scientists have created a high-tech dressing that changes colour if the wound it covers becomes infected — thanks to a dye that can monitor changes in the body’s acidity levels.

While our body’s defences can heal small injuries within a few days, a gaping wound takes longer to heal and an infection can quickly take hold.

Dressings protect the site of the injury but to check the wound they have to be removed.

However, smart bandages and plasters turn from yellow to purple if an infection is present, reports the Daily Mail.

This allows doctors to check the injury without having to change the dressing each time. It saves patients from unnecessary discomfort and also reduces the risk of germs entering the wound.

The intelligent material was developed by scientists at the Fraunhofer Research Institution for Modular Solid State Technologies EMFT in Germany.

“We have developed an indicator dye which reacts to different pH values, and we have integrated it into a dressing and a plaster,” said lead researcher Sabine Trupp.

A pH value is a method of expressing differences in the acidity or alkalinity of a solution.

“Healthy skin and healed wounds usually show a pH value of below five. If this value increases, it is shifting from the acid to the alkaline range, which indicates complications in the healing of the wound.

“If the pH value is between 6.5 and 8.5, an infection is frequently present and the indicator colour strip turns purple,” Trupp said.