A Wearable Surface-Enhanced Raman Scattering Sensor for Label-Free Molecular Detection

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Wearable sensors are crucial for continuous health monitoring.
• Developing non-invasive methods for detecting biomarkers in sweat is a significant challenge.
• Surface-enhanced Raman scattering (SERS) offers high sensitivity for molecular detection.

Purpose of the Study:

• To develop a wearable SERS patch sensor for molecular sweat analysis.
• To investigate the potential of this patch for label-free drug detection.
• To demonstrate its feasibility for real-time healthcare monitoring.

Main Methods:

• Fabrication of a multi-layered SERS patch: silk fibroin protein film (SFF) as the base, a silver nanowire (AgNW) layer for signal enhancement, and a dermal protecting layer (DP).
• Utilizing the SFF's nanoporous structure for molecular filtration and absorption.
• Employing a label-free SERS approach for molecular detection through the transparent DP layer.
• Testing the sensor's performance using 2-fluoro-methamphetamine (2-FMA) on human cadaver skin.

Main Results:

• The SERS patch effectively absorbed sweat and filtered molecules.
• The AgNW layer significantly enhanced Raman signals for label-free detection.
• Successful detection of 2-FMA in sweat demonstrated the sensor's drug detection capability.
• The patch maintained functionality without detachment during measurement.

Conclusions:

• The developed SERS patch is a viable wearable sensor for molecular sweat analysis.
• This technology holds promise for non-invasive drug detection and continuous health monitoring.
• The flexible and wearable nature of the SERS patch opens avenues for diverse biosensing applications.