In the halls of Capitol Hill, a rancorous battle rages over how to deliver better healthcare to the public. But in the nation’s biotechnology labs—and in a few overseas—scientists and engineers are staging a quieter revolution in basic patient care. In recent years, interdisciplinary teams of nanoscientists, engineers and surgeons have revolutionized the way we treat some of our most basic injuries—cuts, scrapes and wounds. Their work has lead to wound dressings that dramatically speed clotting, prevent scar formation or encourage healing, as well as new interventions that don’t look anything like your childhood Band-Aids. In many cases, the new bandages look deceptively low-tech. Some of them are already in use, but the incredible new technologies may not even be visible to the patients who wear them.
HemCon Medical Technologies manufactures bandages and wound dressings that harness the power of the sea. The company’s products use chitosan, a biopolymer made from a component in the exoskeletons of crab, shrimp and other crustacean exoskeletons. The positively charged chitosan attracts the negatively charged outer membranes of red blood cells; when the two come into contact, localized clotting occurs. HemCon’s chitosan-coated bandages are already in use in Iraq; its latest product is ChitoGauze.
The ability of geckos to scale vertical surfaces comes from the special topography of their feet: nano-size hairs gives their feet an adhesive property. Robert Langer, Jeffrey M. Karp and their colleagues at MIT created a gecko-inspired bandage, covered with synthetic versions of these hairs. The bandage can stick to wet surfaces—like the heart itself—and it biodegrades over time, meaning that surgeons can use it to help repair internal injuries.
The family of QuikClot products make use of kaolin clay, a natural blood-clotter. The tiny particles of aluminosilicate contained in the clay have been known for decades to trigger the body’s clotting cascade. Bandages coated with these particles, made by Z-Medica Corporation, have already been used successfully on the battlefields of Iraq and Afghanistan as well by law-enforcement and disaster-preparedness teams in the U.S. The newest product in the family, QuikClot Emergency Dressing, is designed to be used in hospitals and for everyday injuries.
Forget bandages—make way for sound. George Lewis, a graduate student in biomedical engineering at Cornell University, developed a pocket-size machine that administers high-energy ultrasound waves. The waves are powerful enough that they can cauterize an open wound and stop it from bleeding—the tool’s inventor foresees military medics and EMTs carrying the cell-phone-size devices in their pockets, allowing them to treat severe bleeds in the field.
Scientists at the University of Sheffield have created a superfine, biodegradable bandage that acts as a skin farm over the wound. Doctors take a biopsy of patients’ skin cells, which are attached to the scaffold before the dressing is applied over a wound. The skin cells multiply and grow over the scaffold, which eventually dissolves and leaves the patient’s own cells in its stead.
Cut won’t heal? Electrocute it. Research has shown that the skin’s own microcurrents play an important role in wound healing. Clinical trials have now shown that a bandage that distributes mild electrical current across the surface of a wound significantly speeds healing—even for wounds that have proved resistant to other treatments. The surface of the bandage, a product of biotechnology company Vomaris, is covered in microbatteries which are inert when dry. Wetting the bandage activates the circuit, and small currents are applied over the surface of the wound.
University of Delaware researchers Joel Schneider and Darrin Pochan have patented a novel hydrogel composed of self-assembling peptides; when the gel is injected into a wound, it becomes rigid. But because it remains porous, the researchers hope it will be able to deliver drugs or regenerative cells into a wound. (Recent research from their labs reveals that living cells can, indeed, be encapsulated in this gel and successfully delivered into a wound.) The gels also have antimicrobial properties.