Single-molecule surface-enhanced Raman scattering: From exceptional sensitivity to reliable interpretation

Area of Science:

• Nanoscience and Spectroscopy
• Chemical Physics
• Surface Science

Background:

• Single-molecule surface-enhanced Raman scattering (SM-SERS) detects individual molecules but faces challenges in interpreting complex spectral data.
• The recorded spectrum is influenced by a coupled system including molecule-interface, nanocavity, and detection conditions.

Purpose of the Study:

• To shift the focus of SM-SERS evaluation from detection capability to the reliability of scientific conclusions.
• To propose evidential standards for different classes of SM-SERS claims (occupancy, assignment, local state, mechanism).
• To guide the field toward trustworthy nanospectroscopic tool development.

Main Methods:

• Proposed a framework for evidential standards based on claim strength.
• Advocated for multimodal and correlative validation approaches.
• Assessed how different SM-SERS platforms mitigate uncertainty sources.

Main Results:

• Identified key priorities for enhancing SM-SERS reliability: transparent reporting, quantitative statistics, and hypothesis-driven controls.
• Highlighted the need for evidence that addresses uncertainties from the coupled local system.

Conclusions:

• SM-SERS interpretation relies heavily on well-defined measurement conditions, not just signal detection.
• Multimodal validation and transparent reporting are crucial for establishing trust in SM-SERS findings.
• Future SM-SERS research should prioritize robust validation to ensure scientific rigor.