Noise Management of Surface-Enhanced Raman Spectroscopy Using Two-Dimensional Materials

Area of Science:

• Nanotechnology
• Spectroscopy
• Materials Science

Background:

• Surface-enhanced Raman spectroscopy (SERS) is a sensitive technique for biomolecular detection.
• SERS performance is often limited by substrate-induced signal non-uniformity and noise.
• Developing stable and uniform SERS substrates is crucial for reliable biosensing.

Purpose of the Study:

• To design and evaluate hybrid SERS substrates incorporating gold nanoparticles (AuNP) and two-dimensional (2D) materials for improved noise management.
• To investigate the impact of 2D materials on spectral uniformity and signal-to-noise ratio (SNR) in SERS.
• To demonstrate the enhanced biosensing capabilities of these novel hybrid substrates.

Main Methods:

• Fabrication of hybrid SERS substrates using AuNP and 2D materials (graphene, MoS2, WSe2).
• Characterization of spectral uniformity and SNR using SERS measurements.
• Full-wave electromagnetic simulations based on Maxwell's equations to understand noise mechanisms.
• Demonstration of biosensing using a specific protein biomarker.

Main Results:

• Hybrid AuNP/2D material substrates exhibited significantly improved spectral uniformity and SNR compared to conventional AuNP substrates.
• The AuNP/graphene platform demonstrated a ~67% reduction in noise and a ~279% increase in SNR.
• Simulations revealed that the optical properties of 2D materials and nanoparticle distribution are key factors influencing noise.
• Enhanced sensitivity was achieved, with a limit of detection (LOD) of 10^-9 M for a receptor binding domain protein using AuNP/graphene.

Conclusions:

• Hybrid AuNP/2D material substrates offer an effective strategy for noise-managed SERS.
• These platforms provide enhanced sensitivity and reliability for various biosensing applications.
• The findings pave the way for advanced SERS-based diagnostics and molecular detection.