Plaster that seals a wound and peels off painlessly

AHIGH-TECH plaster that comes off without hurting the skin or pulling hairs could make treatment of cuts and wounds much less painful.

The experimental plaster, being developed by scientists at

Pennsylvania University, U.S., painlessly peels off the skin after being soaked in water for just a few seconds.

But while on the skin, it is designed to stick twice as well as current bandages — reducing the chances of wounds coming into contact with bacteria, dirt or

friction that might slow their healing rate.

The plaster is designed for use on wounds that might require treatment at home or in hospital.

Standard adhesive versions can be almost as painful to remove as the injury itself — especially if the skin underneath is soft or hairy.

As the plaster is taken off, the adhesive can strip off the stratum corneum — the very outer layer of skin — causing significant pain.

Hairs can also be yanked from their roots during the removal process.

Whether it’s best to remove plasters in one swift movement, or slowly peel them away, was the subject of a 2009 study by doctors at the Townsville Hospital in Queensland, Australia, and published in the Medical Journal of Australia. This found that slow removal was almost twice as painful as ripping them off in one go.

Current advice from manufacturers is to soak the area in warm water before carefully lifting the

plaster off, or hold an ice pack

THE sticky sap from an Australian tree may help heal chronic wounds, according to a new study in Science Translational Medicine. Scientists from Cardiff University have developed a gel using a molecule from the sap of the blushwood tree — the molecule is thought to stop bacteria taking hold and is also believed to prompt the production of healing proteins. Animal tests found that the gel improved wound healing and the team will now start human trials. against the plaster for several

minutes so that the cold makes the adhesive more brittle and easier to remove.

But the Pennsylvania team has now developed plasters with stronger adhesion (as many of those used at the moment can

quickly come loose, exposing the wound to the risk of infection) yet are less painful to remove.

Most plasters either use glue that gives a very strong bond but

is hard to shift, or is easier to shift but tends to lose adhesion quickly.

The glue used in the new plaster contains a chemical called vinyl

alcohol — commonly found in pots of PVA glue used in classrooms — and boric acid, another chemical often used in antiseptic lotions, according to findings published in August in

the Proceedings of the National Academy of Sciences.

Scientists found that when atoms in the boric acid come into contact with the vinyl alcohol, the pair bond to form a very strong adhesive. But when the glue is exposed to water for just 30 seconds, those same atoms quickly detach from the alcohol molecules to bind instead with the water molecules. This instantly removed the glue’s adhesive properties.

DURING lab tests, scientists applied the experimental glue to glass, which showed it had stronger adhesion than those currently used in plasters.

Separate tests on mice showed it left hairs almost entirely intact when it came to removal.

Scientists are planning further studies and said they hope it will lead to ‘the next generation’ of wound dressing adhesives.

Ash Mosahebi, a professor of plastic surgery at the Royal Free Hospital, London, said: ‘This sounds quite interesting. Anything that is more gentle on the skin, especially for young children and the elderly, is to be welcomed.’