Stretchable ionic-electronic bilayer hydrogel electronics enable in situ detection of solid-state epidermal...

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Continuous health monitoring relies on detecting biomarkers in biofluids like sweat, but accessibility is a major limitation.
• Existing methods often require invasive procedures or are hindered by challenges in biofluid collection and stability.

Purpose of the Study:

• To develop a novel sensor for in situ, continuous detection of solid-state biomarkers directly on human skin.
• To overcome the limitations of biofluid accessibility for real-time health data acquisition.

Main Methods:

• Utilized an ionic-electronic bilayer hydrogel for sequential dissolution, diffusion, and electrochemical reaction of solid-state analytes.
• Developed stretchable wearable sensors for epidermal biomarker detection.
• Validated sensor performance with water-soluble (lactate) and water-insoluble (cholesterol) analytes.

Main Results:

• Achieved ultralow detection limits for solid lactate (0.51 nmol cm⁻²) and solid cholesterol (0.26 nmol cm⁻²).
• Demonstrated a threefold reduction in motion artifacts compared to conventional liquid-sensing interfaces.
• Clinical studies showed high correlation between epidermal biomarkers and blood biomarkers, dynamically reflecting physiological activities.

Conclusions:

• The developed sensor platform enables non-invasive, continuous monitoring of epidermal biomarkers without biofluid acquisition.
• This technology offers a universal approach for health diagnostics and physiological monitoring.
• The ionic-electronic hydrogel interface presents a promising strategy for advanced wearable biosensing.