Ultra-thin dressing for curvy body parts

Scientists have developed novel ultra-thin coatings that can cling to the body's most difficult-to-protect curves, wrinkles and ridges and keep bacteria at bay.
Wrapping wound dressings around fingers and toes can be tricky, but for burn victims, guarding them against infection is critical.
Researcher Yosuke Okamura from Tokai University in Japan explains that existing wound dressings work well when it comes to treating burns on relatively flat and broad areas.
But the human body has curves, wrinkles and ridges that present problems for these dressings.
Okamura's team developed a novel biomaterial out of tiny pieces of nanosheets that are super-flexible and sticky.

"The nanosheets can adhere not only to flat surfaces, but also to uneven and irregular surfaces without adding any adhesives," he said.

That would make a big difference in the way burn victims are treated. Burn wounds are vulnerable to infection, and keeping them sealed off from bacteria is essential for a successful recovery.
Okamura's team makes the nanosheets out of a biodegradable polyester called poly(L-lactic acid), or PLLA.
They put the material into a test tube with water and spin it, which breaks up the sheets into even smaller pieces. When they pour the liquid onto a flat surface, the tiny fragments overlap in a patchwork and dry as a single nanosheet.

They tested out the nanosheets' ability to coat small and irregular shapes by dipping different things into the mixture, including a metal needle and a mouse's fingers.
The nanosheet patchwork effectively covered even the smallest bumps and wrinkles on the mouse's digits, and after the material dried, it clung in place.
When the researchers tested the nanosheets on burns, the dressing effectively kept out the common bacteria, Pseudomonas aeruginosa.
This species of pathogen is often a culprit in skin infections and is notorious for causing hospital-acquired infections that can be deadly. Multi-drug resistant strains are also a serious concern, researchers said.

The dressing protected wounds from infection for three continuous days. With an additional coating, the nanosheets kept bacteria out for a total of six days.
That means the material, if eventually approved for human patients, could cut down the number of times dressings have to be changed.