Many of us can list our Top 5 Most Fun glow in the dark products, but did you know that photoluminescent technology has more serious applications as well? In today’s blog we explore a new scientific application for glow: Glowing bandages that facilitate wound healing.
Phosphorescence, the glow-in-the-dark property used in diverse objects from neon signs to glow sticks, has a new application: aiding in the healing process. Phosphorescence is produced by phosphors, which are molecules that absorb UV energy and then emit light. The brightness of the glowing light is partially influenced by the presence of oxygen. When oxygen levels are low, the glow is very bright, and at higher oxygen levels the glow is diminished.
Dr. Conor Evans of the Wellman Center for Photomedicine at Massachusetts General Hospital and Harvard Medical School is leading a team of researchers to discover how this oxygen-dependant glow might be applied in medical diagnostics and treatment. Their focus is centered on wound care and healing, a biological process that is also oxygen-dependant. Damaged tissue requires blood flow to the area in order to heal, and oxygen is crucial for cellular repair. A high level of oxygen in the wounded tissue means that nutrient-rich blood is flowing to the region, and that the wound is healing. Evans and his colleagues have created a liquid bandage with glow in the dark materials. It uses phosphors to measure and map the changing levels of oxygenation at the wound site.
So just how does this incredible bandage work? It assesses critical conditions such as the rate and depth of healing in wounds and burns. This special see-through liquid is a combination of a long-lasting phosphor and a nitrocellulose bandage material that is painted on, sealing the skin surface. It dries quickly (in 1 minute) and then a separate barrier layer is painted on top to prevent the oxygen in the air from interfering with the signal. This way, only the oxygen in the tissue is measured. This also aids in protecting the wound by keeping bacteria at the wound site to a minimum.
An external device then provides a burst of light (similar to a camera flash) that triggers the emission of phosphorescence. Because of the phosphors present, when the oxygen levels are high, the bandage glows green, and when the oxygen levels are low, the bandage glows red. The same device that provided the flash captures these signals and records them, ultimately creating a map of the changes in oxygenation levels, either over time or in regional differences. When the patient is finished with the bandage, it peels off painlessly (and without harming the wound) because the underside has dried to a clean gel.
This SMART bandage is important for several reasons. Currently the best alternate method of assessing the efficiency of wound treatment is by inserting electrodes into the wounded area, or an expensive and somewhat inaccessible PET scan. Evans’ team’s liquid bandage is non-invasive, inexpensive, and efficient. They are interested in developing apps used with cell phone cameras to trigger and measure the phosphor emissions. They hope that someday these specialty bandages could also measure pH levels, sense bacteria, and even administer drugs. Best of all, it could be over-the-counter and used from home, making it accessible, affordable and tailored for individual use.
Thanks to continuous advances in photoluminescent technology, the future of wound care is looking bright!