Researchers just developed a compression bandage that changes color depending on its tightness.
A compression bandage is typically used to treat specific medical issues involving veins that don’t provide enough blood to the limbs. Primarily, the dressing is used to stimulate the blood flow coming from the legs and arms.
However, one downside to using compression bandages is that there is no way to know whether the applied pressure is enough for that particular condition.
As a solution, engineers at Massachusets Institue of Technology created a bandage that changes color depending on how much the material is stretched.
How does it work?
When medical personnel stretch a patient’s bandages just enough to apply pressure, the color-changing photonic fibers change color. These can then be used to visually check the amount of pressure the bandage is applying.
“Getting the pressure right is critical in treating many medical conditions including venous ulcers, which affect several hundred thousand patients in the US each year,” Mathias Kolle of MIT said in a statement.
“These fibers can provide information about the pressure that the bandage exerts. We can design them so that for a specific desired pressure, the fibers reflect an easily distinguished color.”
The color produced by the fibers comes from a carefully designed structural configuration. The size of each fiber is about ten times the diameter of a human hair.
The MIT researchers made the fiber from ultrathin layers of transparent rubber materials that they then rolled up to create a jelly-roll-type structure.
The rolled-up configuration of the fibers allows light to reflect off the interface between each layer. The reflections interact to strengthen some colors in the visible spectrum depending on the pressure on the bandage. This enables the compression bandage to show a specific color depending on the thickness of the layers of the fiber.
“Structural color is really neat because you can get brighter, stronger colors than with inks or dyes just by using particular arrangements of transparent materials. These colors persist as long as the structure is maintained,” Joseph Sandt explained.
The researchers published details about the color-changing compression bandage in the journal Advanced Healthcare Materials.