Magnetic Porous Hydrogel-Enhanced Wearable Patch Sensor for Sweat Zinc Ion Monitoring

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Wearable sensors for sweat analysis face challenges in efficient sweat collection and real-time signal detection.
• Current methods require significant exercise to induce sweating, leading to delayed and prolonged detection signals that do not reflect real-time bodily changes.

Purpose of the Study:

• To develop a multifunctional hydrogel-based wearable sensor for real-time monitoring of zinc ions (Zn²⁺) in human sweat.
• To address the limitations of existing sweat detection technologies, including slow sweat collection and delayed signal recording.

Main Methods:

• Fabrication of a multifunctional hydrogel with magnetic and porous properties using Fe₃O₄ nanoparticles.
• Integration of the hydrogel with a flexible patch electrode to create a wearable sensing platform.
• Utilizing differential pulsed anodic striping voltammetry (DPASV) for Zn²⁺ detection.

Main Results:

• The hydrogel's porous structure facilitated rapid sweat absorption, while Fe₃O₄ nanoparticles enhanced conductivity and structural adjustability.
• The developed sensing platform demonstrated a linear relationship for Zn²⁺ detection within the concentration range of 0.16–16 µg/mL.
• Successful real-time detection of sweat Zn²⁺ in four volunteers during both exercise and resting states.

Conclusions:

• The novel hydrogel-based wearable sensor enables rapid and real-time monitoring of sweat Zn²⁺.
• This technology overcomes key challenges in sweat collection and detection, offering a promising approach for physiological monitoring.
• The platform shows potential for commercial applications in non-invasive health diagnostics.