'Nanosheets' to protect from burn wound infections

A new 'nano' coating technology promises to dress burn wounds not only on the flat and broad part of human body but also at curves, wrinkles and ridges to heal and control bacterial infections.

The ultrathin coatings called "nanosheets" can cling to the body's most difficult-to-protect contours and keep bacteria at bay, Japanese researchers reported.

The team led by Yosuke Okamura from Tokyo-based Tokai University 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 added.

When researchers tested the nanosheets on burns, the dressing effectively kept out the common bacteria called pseudomonas aeruginosa that causes deadly skin infections.

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.

"Burn wounds are vulnerable to infection and keeping them sealed off from bacteria is essential for a successful recovery," Okamura noted.

The team made "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 broke up the sheets into even smaller pieces.

When they poured the liquid onto a flat surface, the tiny fragments overlapped in a patchwork and got dried as a single "nanosheet".

The findings were recently presented at the 248th meeting of the American Chemical Society (ACS), the world's largest scientific society.