WASHINGTON, July 7 (Xinhua) -- American engineers have developed a prototype bandage designed to actively monitor the condition of chronic wounds and deliver appropriate drug treatments to improve the chances of healing.
The research published in the latest journal Small 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 and other medical conditions can overwhelm the regenerative capabilities of the skin and often lead to persistent infections and amputations.
The researchers from Tufts University designed the bandages with heating elements and thermos-responsive drug carriers that can deliver tailored treatments in response to embedded pH and temperature sensors that track infection and inflammation.
Patients with non-healing chronic wounds are often older, non-ambulatory, and limited in their ability to provide self-care. The smart bandages could provide real time monitoring and delivery of treatment with limited intervention from the patient or caregivers.
"We've been able to take a new approach to bandages because of the emergence of flexible electronics," said Sameer Sonkusale, professor of electrical and computer engineering at Tufts University's School of Engineering and corresponding co-author for the study.
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.
Also, temperature is an important parameter, providing information on the level of inflammation in and around the wound.
The smart bandages in this study combine pH and temperature sensors, and are also integrated with flexible sensors for oxygenation, another marker of healing. Inflammation could also be tracked not just by heat, but by specific biomarkers.
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 three 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 we created, with pH and temperature sensors and antibiotic drug delivery, is really a prototype for a wide range of possibilities," said Sonkusale. "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.