A research team at the National University of Singapore (NUS) has developed a smart wearable sensor that can conduct real-time, point-of-care assessment of chronic wounds wirelessly via an app.

VeCare technology can detect temperature, pH, bacteria type and inflammatory factors specific to chronic wounds within 15 minutes, enabling fast and accurate wound assessment.

It consists of a wound sensing bandage, an electronic chip and a mobile app. The bandage comprises a wound contact layer, a breathable outer barrier, a microfluidic wound fluid collector and a flexible immunosensor.

Bacteria type

VeCare is the first wound assessment platform that can detect bacteria type and probe inflammatory factors, in addition to measuring acidity and temperature, within a single 15-minute test. The immunosensing bandage enables rapid assessment of wound microenvironment, inflammation and infection state by detecting multiple chronic wound-specific biomarkers from wound fluid using an electrochemical system. The microfluidic wound fluid collector attached to the sensor directs and boosts wound fluid delivery to the sensor by up to 180%. The design ensures reliable sensing performance regardless of the ulcer shape or size.

In addition, a chip integrated with flexible electronics is connected to the sensor to transmit data wirelessly to an app for convenient, real-time wound assessment and analysis onsite. The chip component, powered with a rechargeable battery, can be reused for subsequent applications.

Home freedom

“Point-of-care devices coupled with telehealth or digital health capability can play a significant role in transforming the healthcare industry and our society, which is catalysed by the Covid-19 pandemic requirements for safe distancing,” said Professor Lim Chwee Teck, director of iHealthtech at NUS, who led the work in collaboration with clinical partners from Singapore General Hospital. “Our smart bandage technology is the first of its kind designed for chronic wound management to give patients the freedom to perform the test and monitor their wound conditions at home.”

With a rapidly ageing population, healthcare providers are seeing more patients suffering from non-healing wounds such as diabetic foot and chronic venous leg ulcers. It has been estimated that about 2% of the world’s population suffer from chronic wounds. The healing processes for these wounds are often interrupted due to infection or repeated trauma, leading to severe stress, pain and discomfort for patients. For patients with diabetic foot ulcers, this can lead to more severe outcomes such as foot amputation. Timely care and proper treatment of chronic wounds is needed to speed up wound recovery but it currently requires multiple clinical visits for lengthy wound assessment and treatment, which adds to the healthcare cost. The NUS team’s innovation can help mitigate these consequences and relieve patients with chronic wounds from unnecessary distress.

Limited markers

Current clinical assessments of wounds rely on visual inspection, or collecting and sending wound fluid to a centralised lab to detect and analyse specific biomarkers. The whole process usually takes about one to two days and may impede proper, timely and precise medical interventions. Although there are recent developments in flexible sensors designed for wound care, they can only probe a limited set of markers such as acidity, temperature, oxygen, uric acid, and impedance to diagnose wound inflammation.

In collaboration with the Singapore General Hospital, a small clinical test of VeCare was conducted on patients with chronic venous leg ulcers. They successfully demonstrated that the platform is effective in the assessment of chronic wounds and enabling monitoring of the progress of wound healing with timely medical intervention.

“The VeCare platform is easily scalable and customisable to accommodate different panels of biomarkers to monitor various types of wounds,” said Professor Lim. “The aim is to have an effective and easy to use diagnostic and prognostic tool for precise and data-driven clinical management of patients,”

The next step for the research team is to further develop VeCare to meet safety, regulatory and mass production considerations. The team will explore the incorporation of other appropriate biomarkers suitable for other wound types and utilise data in existing clinical workflows to improve diagnosis and treatment. They hope to test the technology on a larger prospective randomised clinical trial with different types of non-healing chronic ulcers such as diabetic foot and pressure ulcers.

www.nus.edu.sg