THE humble sticking plaster is getting a high-tech upgrade. As well as simply patching up small cuts and grazes, plasters embedded with light-emitting diodes could be used to treat skin cancer in combination with light-sensitive drugs.

Polymertronics, based in Banbury, UK, is developing the plasters, which are impregnated with a ser ies of organic light-emitting diodes (OLEDs).

The light plasters are designed for use in photodynamic therapy, in which light-sensitive drugs are applied to the skin as a cream.

When you shine red light on the area it activates the drugs, which destroy the tumour as they soak though the skin.

At the moment, expensive lamps and lasers supply the red light for photodynamic therapy, and so the treatment can only be performed in hospitals

The light plasters could allow people with skin cancer to treat themselves at home, says Stephen Clemmet, CEO of Polymertronics. We're looking at developing a faster, cheaper, easier way to treat skin cancer.

OLEDs emit light when a voltage is applied to them. The company has developed a way to print square clusters of battery-powered red OLEDs, each 4 millimetres square, onto a strip of flexible plastic. The pattern of OLEDs exactly matches the shape of the patient's tumour. The plaster is then placed over the tumour, allowing the red light to be targeted directly at the cancerous tissue.

The company has shown that its OLEDs are able to destroy a range of cancer cells in the laboratory, and will soon begin human trials of the light-emitting plasters

It presented the devices at a meeting on polymer electronics in London on 21 April, and hopes to launch them commercially within two years.

Another UK company, Lumicure, a spin-off from the University of St Andrews, is working on a similar OLED-plaster, also for treating skin cancer.