New Wearable Device Monitors Skin Issues in Real Time

A first-of-its-kind wearable device that measures gases emitted by the skin may improve the ways to assess skin health, from tracking hydration levels to measuring exposure to harmful environmental chemicals.

The skin is the largest organ in the human body, acting as a protective barrier. It may also serve as a telltale sign of underlying conditions like polycystic ovary syndrome (PCOS) or high cholesterol, according to the American Academy of Dermatology Association.

Assessing skin health may soon become easier, thanks to a new wearable, no-contact device developed by Northwestern University researchers. The discovery can provide continuous remote patient monitoring, giving valuable insight into various skin conditions and overall health.

As described in the study published in the peer-reviewed journal Nature, the device comprises a collection of sensors that measure changes in temperature, water vapor, carbon dioxide (CO2), and volatile organic compounds (VOCs), chemicals commonly found inside and outdoors.

Revolutionizing water loss assessment

The outermost layer of skin, also called the skin barrier, is the body’s first line of defense from the external environment, guarding against irritants, bacteria, and ultraviolet radiation. By preventing excessive water loss, it maintains skin hydration.

Compromising the skin barrier may lead to increased water loss, known as transepidermal water loss (TEWL), and skin sensitivity. It can also raise the risk of infection and inflammatory skin conditions like eczema and psoriasis.

The new device assesses the integrity of the skin barrier by tracking changes in the emission of water vapor and gases from the skin.

Existing technologies to measure water vapor loss are large, heavy machines usually available in hospital settings. Meanwhile, the new wearable device is compact and allows remote monitoring of patients at home.

“Having a device that can measure transepidermal water loss remotely, continuously or as programmed by the investigator — and without perturbing a patient during sleep — is a major advance,” a co-author of the study, Dr. Amy Paller, the Walter J. Hamlin Professor of Dermatology and chair of the Department of Dermatology at Feinberg, said in a statement.

How does it work?

The device is just two centimeters long and one-and-a-half centimeters wide. It comprises a chamber, a collection of sensors, a programmable valve, an electronic circuit, and a small rechargeable battery.

The chamber hovers a few millimeters above the skin, gathering information about fragile skin without disturbing delicate tissues.

An automatic valve opens and closes the chamber's entrance, dynamically controlling access between the enclosed chamber and the surrounding ambient air.

When the valve is open, gases flow in or out of the chamber, enabling the device to establish a baseline measurement. Then, the valve rapidly closes, trapping gases within the chamber. From there, the series of sensors measure changes in gas concentrations over time.

The device sends this data to a smartphone or tablet via Bluetooth, allowing real-time monitoring. The study authors say the fast results can help healthcare providers make more informed decisions, such as prescribing antibiotics more timely.

They argue that the device may improve infection detection, as increased water vapor, CO2, and VOCs are associated with bacterial growth and delayed healing.

Continuous monitoring is particularly crucial for diabetic ulcers, which are the number one non-traumatic cause of lower limb amputations worldwide.

Sometimes it might appear that the wound is closing, but the skin barrier function is not quite restored. Our device can precisely measure emitted gases, which provides useful information about the skin barrier function.

Dr. Guillermo A. Ameer

The technology may open new avenues for monitoring the efficacy of a wide range of products designed to improve skin health.

Because CO2 and VOCs attract mosquitos and other pests, measuring these emissions from the skin could help scientists understand and potentially mitigate mosquito attraction.

The new device could also measure how fast lotions and creams penetrate the skin, providing data that could be used in the development of more effective transdermal drug delivery systems. It could also monitor the effects of systemically delivered drugs for skin diseases and evaluate the safety of cosmetics and personal care products.

Overall, the next steps for the Northwestern researchers include refining the device and adding a sensor to track changes in pH levels. When we'll see the device hasn't been announced yet but once we do, patients will be empowered to prioritize their skin health and take monitoring into their own hands.