Smart Textile Monitors Your Health Without You Moving a Muscle

A new textile biosensing system uses low-current iontophoresis to trigger sweat and analyze biomarkers without requiring exercise or heat.

A fabric-based electrochemical biosensing system developed by He et al. enables automatic sweat collection and real-time molecular analysis without requiring physical activity ().

Built at Tsinghua University, the system addresses the longstanding challenge of sweat’s passive and activity-dependent nature, allowing broader applications of sweat-based health monitoring.

New Wearable Device Measures Cortisol in Sweat
New wearable patch was designed by researchers to measure cortisol in sweat. The finding offers novel approach for the early detection of various diseases and evaluation of sports performance.

TOP INSIGHT

Did You Know?
Wearable fabric sensors can now collect and analyze your sweat without any physical activity, using just 75 microamperes of painless current. #medindia #wearabletech #healthmonitoring

Triggering Sweat Effortlessly

At the heart of this system lies a low-current iontophoresis module embedded in a breathable textile. It uses a skin-interfaced stabilized hydrogel (SSIH) electrode to deliver a mild current that activates sweat glands in a controlled and painless manner. This hydrogel ensures tight contact with the skin, enabling effective ionic delivery while minimizing discomfort and signal loss.

“We designed the interface to be soft, conformal, and electrically stable over time,” explains Prof. Sisi He, the corresponding authors of the study. “For efficient agonist delivery, the electrode also needed to achieve a delicate balance among drug transport efficiency, mechanical compliance with skin, biocompatibility, and long-term operational stability. These properties allow us to stimulate local sweating without relying on user movement or heat, which greatly broadens the scenarios where sweat biosensing can be applied.”

Smart Masks for Monitoring Breath Health
New smart mask analyzes breath to monitor health markers like inflammation and alcohol levels.

Low-Current Iontophoresis and Skin Comfort

In trials with human volunteers, the sweat induction module reliably triggered localized perspiration within minutes using a current as low as 75 microamperes. This is significantly lower than the milliampere-level currents typically required by conventional iontophoresis systems.

The amount of sweat induced was sufficient to activate downstream sensing modules. The stimulation caused no skin irritation or discomfort, even after repeated use.

Saliva And Tears: Wearabe Device Monitors Health And Administers Drugs
Micro and nano device technology can be used for diagnosis and also administration of drugs through the saliva and tears.

Enzymatic Detection and Electrochemical Stability

Once sweat is induced, it flows through a hydrophilic layer toward biosensing fibers integrated into the textile. These fiber sensors, constructed with coaxial carbon nanotube electrodes, are modified with enzymes or conductive materials that enable the detection of multiple biomarkers, including glucose, lactate, uric acid, and pH. Moreover, to improve the long-term stability of the redox interface used for enzymatic signal transduction, the researchers introduced a nickel hexacyanoferrate (NiHCF) coating to reinforce the Prussian Blue layer.

As a member of the Prussian Blue Analogue (PBA) family, NiHCF offers superior electrochemical stability compared to conventional Prussian Blue, which is prone to structural degradation and signal loss under repeated operation in physiological conditions. This modification enabled the sensors to deliver stable and repeatable signals during continuous monitoring for over 6 hours.

Novel 3D-Printed Glucose Biosensors Discovered
New 3D-printed glucose biosensor developed may lead to improved glucose monitors for people who have diabetes.

Integration into Daily Wear and User-Friendly Design

To evaluate the system’s usability beyond the lab, the team seamlessly integrated the sweat stimulation and sensing modules into everyday clothing. The soft textile interface conformed comfortably to body areas such as the forearm and upper back, enabling long-term monitoring during common daily activities such as sitting at a desk, reading, or even sleeping.

“Our goal was to enable physiological monitoring that blends naturally into people’s lives,” says Prof. Sisi He. “This platform operates autonomously and responds on demand, making it fundamentally more inclusive.”

Reference: