Universities Develop New Wearable Health Monitoring Devices Including Smart Tattoos and Sweat-Tracking Rings

Universities are driving the next generation of wearable health technology by developing highly integrated, non-invasive monitoring devices. Engineers at UC San Diego have created a 3D-printed smart ring that uses an osmotic hydrogel to passively extract sweat and analyze up to four biomarkers, such as glucose and lactate, in real time. Meanwhile, Penn State researchers have developed a paintable, conductive ink for temporary smart tattoos that adhere directly to the skin to track ECG readings and even control prosthetic limbs. While these innovations promise deeper biochemical insights, experts caution that consumer wearables still provide estimates rather than clinical-grade diagnoses.

Wearable health technology overview

• ▪Wearable health devices process collected physiological data using software algorithms and display it through companion mobile applications or digital dashboards.
• ▪Wearable health technology refers to electronic devices worn on the body that use built-in sensors to monitor health, fitness, or medical information.

Device types available

• ▪Engineers at the University of California San Diego developed a 3D-printed prototype smart ring that continuously and passively tracks up to four biomarkers in sweat simultaneously.
• ▪Penn State engineers developed a paintable, conductive ink for temporary smart tattoos that can power sensors to monitor brain waves, track ECG readings, and control robotic limbs.
• ▪Common wearable health devices include smartwatches, fitness trackers, smart rings, and medical wearables like continuous glucose monitors and wearable ECG monitors.

Health tracking sensors

• ▪Penn State's conductive ink uses a mixture of polymers and acidic additives in a water-based solution that dries onto the skin in less than 10 minutes.
• ▪Wearable devices commonly utilize optical heart rate sensors, accelerometers, gyroscopes, temperature sensors, and blood oxygen sensors to collect physiological data.
• ▪The UC San Diego smart ring uses an osmotic hydrogel to passively draw sweat from the skin and an electrochemical sensor array to analyze biomarker concentrations.

Benefits for users

• ▪Wearable health technology encourages physical activity, improves sleep awareness, supports heart health, and assists in managing chronic conditions like diabetes and high blood pressure.
• ▪Simultaneous multi-biomarker tracking, such as monitoring glucose and ketones, can provide a broader real-time health picture to optimize insulin dosing for diabetes management.

Accuracy limitations

• ▪Conventional electrode designs using stiff metals or hydrogels can lose adhesion, dry out, or struggle to record accurate signals on hairy or sweaty skin.
• ▪Consumer wearables provide estimates rather than clinical-grade measurements, and their accuracy can be affected by device placement, skin tone, tattoos, movement, and poor sensor contact.

Privacy concerns

• ▪Wearable devices collect large amounts of personal health information, making it important for users to review a company's privacy policy and data-sharing practices before purchasing.
• ▪The rapid evolution of wearable health technology includes emerging developments in advanced artificial intelligence for health insights, non-invasive glucose monitoring, and integration with telemedicine services.