For people with diabetes, a wound may not end as a simple skin injury. In particular, a "diabetic ulcer (diabetic foot)" on the foot heals poorly and can lead to infection or tissue necrosis, making it a representative diabetes complication for which amputation may need to be considered if treatment is delayed.
To reduce these risks, a smart dressing patch has been developed that lets users visually check the wound's condition and view numeric readings with a smartphone.
A research team led by Park In-gyu, chaired professor in mechanical engineering at KAIST, along with Hajihwan, a professor at National Hanbat University, Chung Joon-ho, a researcher at the Korea Institute of Machinery & Materials (KIMM), and Wei Gao, a professor at the California Institute of Technology, said on the 14th that they jointly developed a "wireless, battery-free, AUK multimodal sensor patch" for managing diabetic ulcers.
The patch combines a dressing that covers and protects the wound with diagnostic sensors. It can simultaneously monitor changes in glucose concentration, acidity, and temperature at the wound site. Simply put, a single patch reads multiple signals the body shows when a wound worsens.
First, the team fabricated a functional nanofiber dressing using electrospinning. Electrospinning is a technique that draws fibers much thinner than a human hair using an electric field. The dressing thus made changes color when glucose levels rise or acidity shifts in a diabetic foot wound.
In other words, when the wound is likely to worsen, the patch changes color, allowing patients or clinicians to intuitively spot warning signs. Because it is noninvasive and does not require cutting the skin or drawing blood, it can also reduce the burden on patients.
To this, the team added an AUK sensor system. AUK is a technology that uses both light and electrical signals. A light-emitting diode (LED) inside the patch emits light, and a light-detecting sensor called a photodiode reads the dressing's color change as reflectance and converts it into an electrical signal.
With the conventional method of photographing color with a camera, results can vary depending on ambient lighting. In contrast, this patch emits light directly and measures the degree of reflection, yielding more stable data.
The biggest feature of this technology is that it does not require a battery. The patch incorporates a flexible circuit based on near-field communication (NFC). As with smartphone transit cards or simple payments, NFC is a technology that exchanges power and data over short distances.
When the patient brings a smartphone close to the patch, the patch is powered wirelessly and operates. The measured wound information is then transmitted to the smartphone. Without separate equipment or complex testing, the wound's status can be checked immediately through an app.
Park said, "The research we began to ease the pain of people with diabetes who have to prick their fingers with a needle every day has led to a technology for preemptive diagnosis of complications," adding, "This technology will become a core foundational technology that can expand into non-blood-draw diagnostics for a range of chronic diseases beyond diabetes."
The findings were published in January in the international materials science journal "Advanced Functional Materials" and selected as a cover article.
References
Advanced Functional Materials (2026), DOI: https://doi.org/10.1002/adfm.202532167