Gx Sweat Patch

Problem

Hydration is one of the most critical and most misunderstood determinants of athletic performance. Sweat rate and electrolyte loss can vary by several-fold between individuals and even within the same athlete across conditions, yet most hydration strategies still rely on population averages, static formulas, or post-exercise estimates. This knowledge gap leaves athletes vulnerable to dehydration, electrolyte imbalance, cramping, premature fatigue, and avoidable performance decline, particularly during high-intensity training, endurance events, and heat exposure. 

While wearable technologies have transformed how athletes monitor heart rate, movement, and physiology, hydration has remained a blind spot. Existing tools fail to capture real-time, individual sweat loss and electrolyte dynamics during exercise, limiting athletes’ ability to make informed, personalized hydration decisions when they matter most. 

Solution

The Gx Sweat Patch, developed by Epicore Biosystems, is a single-use, skin-adhered biosensor that analyzes sweat composition during exercise. The patch provides real-time insights into fluid and electrolyte loss, enabling athletes to tailor their hydration strategies based on their unique physiology. 

The patch uses colorimetric sensing to measure sweat rate and sodium concentration, translating biological data into actionable recommendations via the Gx App. It’s lightweight, non-invasive, and designed for use during training or competition. 

Benefits

• Personalized Hydration: Delivers individualized fluid and electrolyte recommendations based on actual sweat data. 
• Real-Time Feedback: Syncs with the Gx App to provide hydration guidance during and after workouts. 
• Non-Invasive & Easy-to-Use: Adheres to the skin and collects data passively—no wires, no discomfort. 
• Optimized Performance: Helps reduce risk of dehydration, cramping, and fatigue by aligning hydration with physiology. 

Technology & Commercialization Status

The Gx Sweat Patch traces its origins to pioneering research in soft bioelectronics and microfluidic wearable systems in the laboratory of McCormick Professor John Rogers. Developed in partnership with McCormick Research Associate Professor Roozbeh Ghaffari, this work enabled a new class of skin-interfaced devices capable of capturing and analyzing sweat biomarkers in real time, laying the foundation for personalized hydration monitoring.

In 2018, Professor Ghaffari co-founded Epicore Biosystems to commercialize this technology and advanced it into a scalable wearable biosensing platform. Through a strategic partnership with the Gatorade Sports Science Institute (GSSI), Epicore adapted the technology for athlete performance applications, resulting in the Gx Sweat Patch.

The Gx Sweat Patch provides personalized insights into sweat rate, fluid loss, and electrolyte depletion, helping athletes better understand their hydration needs during training and competition. Integrated with Gatorade’s Gx ecosystem, including the Gx App and connected hydration tools, the patch translates real-time physiological data into individualized hydration recommendations.

Northwestern Inventors

John A. Rogers, PhD,
Louis Simpson and Kimberly Querrey Professor of Materials Science and Engineering 
McCormick School of Engineering 

Roozbeh Ghaffari, PhD
Research Associate Professor of Biomedical Engineering 
McCormick School of Engineering 

Links

Website: www.epicorebiosystems.com