A prototype bandage designed to actively monitor the condition of chronic wounds and deliver appropriate drug treatments to improve the chances of healing has been developed by the researchers at Tufts University (TU). While the lab-tested bandages remain to be assessed in a clinical context, the research is aimed at transforming bandaging from a traditionally passive treatment into a more active paradigm to address a persistent and difficult medical challenge. Chronic skin wounds from burns, diabetes (lat. Diabetes Mellitus), and other medical conditions can overwhelm the regenerative capabilities of the skin and often lead to persistent infections (lat. Infectio) and amputations.
With the idea of providing an assist to the natural healing process, the researchers designed the bandages with heating elements and thermoresponsive drug carriers that can deliver tailored treatments in response to embedded pH and temperature sensors that track infection and inflammation.
The pH of a chronic wound is one of the key parameters for monitoring its progress. Normal healing wounds fall within the range of pH 5.5 to 6.5, whereas non-healing infected wounds can have pH well above 6.5. Temperature is also an important parameter, providing information on the level of inflammation in and around the wound. While the smart bandages in this study combine pH and temperature sensors, the engineers have also developed flexible sensors for oxygenation - another marker of healing - which can be integrated into the bandage. Inflammation could also be tracked not just by heat, but by specific biomarkers as well.
A microprocessor reads the data from the sensors and can release drug on demand from its carriers by heating the gel. The entire construct is attached to a transparent medical tape to form a flexible bandage less than 3 mm thick. Components were selected to keep the bandage low cost and disposable, except for the microprocessor, which can be re-used.
The smart bandage with pH and temperature sensors and antibiotic drug delivery is really a prototype for a wide range of possibilities. One can imagine embedding other sensing components, drugs, and growth factors that treat different conditions in response to different healing markers. The smart bandages have been created and tested successfully under in vitro conditions. Pre-clinical studies are now underway to determine their in vivo clinical advantages in facilitating healing compared to traditional bandages and wound care products.