Wearable Localized Surface Plasmon Resonance-Based Biosensor with Highly Sensitive and Direct Detection of Cortisol...

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Analytical Chemistry

Background:

• Wearable biosensors enable continuous, real-time physiological data collection for personalized health monitoring.
• Localized surface plasmon resonance (LSPR) sensors offer high sensitivity for detecting specific analytes.
• Monitoring cortisol, a primary stress hormone, is crucial for assessing stress, performance, and mental health.

Purpose of the Study:

• To develop a flexible wearable biosensor for sensitive and selective detection of cortisol.
• To investigate the potential of LSPR technology for real-time stress level assessment.

Main Methods:

• Fabrication of a flexible LSPR biosensor by depositing gold nanoparticles (AuNPs) on an APTES-functionalized PDMS substrate.
• Immobilization of cortisol-specific aptamers on the LSPR sensor surface for enhanced capture.
• Characterization of sensor performance, including detection limit, selectivity, and stability under mechanical stress.

Main Results:

• The biosensor demonstrated excellent cortisol detection across concentrations from 0.1 to 1000 nM, with a low detection limit of 0.1 nM.
• The flexible sensor maintained good stability during mechanical deformations.
• In vivo measurements of cortisol levels in human epidermis were successfully performed before/after exercise and at different times of day.

Conclusions:

• A novel, flexible LSPR biosensor capable of highly sensitive and selective cortisol detection has been developed.
• This wearable sensor shows potential for non-invasive, continuous monitoring of human stress levels.
• The developed biosensor represents a versatile platform for developing user-friendly health monitoring products.