We’re a long way from the dermal regenerators in Star Trek, but researchers at Northwestern University have made a leap forward in the convenient use of electrotherapy for wound healing.
Using a ring and center “flower” electrode, this bioresorbable molybdenum device restores the natural bioelectric field across a wound to stimulate healing in diabetic ulcers. Only 30 minutes of electrical stimulation per day was able to show a 30% improvement in healing speed when used with diabetic mice. Power is delivered wirelessly and data is transmitted back via NFC, meaning the device can remain on a patient without leaving them tethered when not being treated.
Healing can be tracked by the change in electrical resistance across the wound since the wound will dry out as it heals. Over a period of six months, the central flower electrode will dissolve into the patient’s body and the rest of the device can be removed. Next steps include testing in a larger animal model and then clinical trials on human diabetic patients.
This isn’t the first time we’ve covered using electricity in medicine.
Continue reading “Electronic Bandage Speeds Wound Healing” →
Here at Hackaday, we’re always enthralled by cool biohacks and sensor development that enable us to better study and analyze the human body. We often find ourselves perusing Google Scholar and PubMed to find the coolest projects even if it means going back in time a year or two. It was one of those scholarly excursions that brought us to this nifty smart bandage for monitoring wound healing by the engineers of FlexiLab at Purdue University. The device uses an omniphobic (hydrophobic and oleophobic) paper-based substrate coupled with an onboard impedance analyzer (AD5933), an electrochemical sensor (the same type of sensor in glucometers) for measuring uric acid and pH (LMP91000), and a 2.4 GHz antenna for wirelessly transmitting the data (nRF24L01). All this is programmed with an Arduino Nano. They even released their source code.
To detect uric acid, they used the enzyme uricase, which is very specific to uric acid and exhibits low cross-reactivity with other compounds. They drop cast uric acid onto a silver/silver chloride electrode printed on the omniphobic paper. Similarly, to detect pH, they drop cast a pH-responsive polymer called polyaniline emeraldine salt (PANI-ES) between two separate silver/silver chloride electrodes. All that was left was to attach the electrodes to the LMP91000, do a bit of programming, and there they were with their own electrochemical sensor. The impedance analyzer was a bit simpler to develop, simply attaching un-modified electrodes to the AD5933 and placing the electrodes on the wound.
The authors noted that the device uses a much simpler manufacturing process compared to smart bandages published by other academics, being compatible with large-scale manufacturing techniques such as roll-to-roll printing. Overcoming manufacturing hurdles is a critical step in getting your idea into the hands of consumers. Though they have a long way to go, FlexiLab appears to be on the right track. We’ll check back in every so often to see what they’re up to.
Until then, take a look at some other electric bandage projects on Hackaday or even make your own electrochemical sensor.
Silverleaf Medical products has created an electric wound dressing that staves off infection by killing microbes in an open wound and preventing other germs from getting in.
They call it the CMB Antimicrobial Wound Dressing, and it is made of polyester fabric woven with a proprietary material called Prosit. When the bandage is moistened, the Prosit generates a low voltage, killing germs in the wound. One of these bandages can be worn for 3 days at a time, and their clinical trials indicate that they are highly effective in treating infected wounds. Take a look at their brochure (PDF file) for some informative and stomach-turning before and after photos.