Surface-Enhanced Raman Spectroscopy Substrates in Paper-Based Systems

Surface-Enhanced Raman Spectroscopy (SERS) harnesses the unique optical properties of noble metal nanostructures to amplify inelastic scattering signals from molecular analytes, enabling trace-level detection across environmental, medical and industrial settings. Paper, with its inherent porosity, capillarity and low cost, has emerged as an ideal support for SERS substrates, combining ease of fabrication with disposability and portability. By decorating cellulose fibres with plasmonic nanoparticles—typically silver or gold—researchers generate dense assemblies of electromagnetic “hotspots” that can enhance Raman signals by orders of magnitude. Recent advances have addressed challenges in substrate uniformity, reproducibility and sensitivity through controlled nanoparticle synthesis, surface chemical modification and novel patterning techniques. Paper-based SERS platforms now promise rapid on-site monitoring of pollutants, pharmaceuticals, biomolecules and food contaminants, with particular emphasis on sustainability and point-of-care diagnostics.

Research from Nature Portfolio

Foundational work has demonstrated that office paper decorated with silver nanostars can serve as a highly effective SERS substrate. By patterning hydrophilic wells on low-porosity paper and drop-casting star-shaped silver nanoparticles, the study revealed that paper porosity governs nanoparticle distribution and hotspot formation. Office paper retained the majority of the nanostars at the illuminated surface, achieving enhancement factors of ~10^7 for rhodamine 6G and detection limits down to picogram levels. The well-patterning approach also delivered exceptional signal uniformity and substrate stability over several weeks, underscoring the potential for long-term storage and field deployment.

Surface-Enhanced Raman Spectroscopy Substrates in Paper-Based Systems publication trend

The graph below shows the total number of articles in surface-enhanced raman spectroscopy substrates in paper-based systems across all publications each year (not limited to Nature Index journals).

Technical terms

Surface-Enhanced Raman Spectroscopy (SERS): A technique that amplifies Raman scattering signals via plasmonic excitation of metal nanostructures, enabling sensitive molecular detection.

Substrate: A solid support, here paper, on which plasmonic nanoparticles are immobilised to create hotspots for signal enhancement.

Plasmonic Nanoparticles: Nanoscale metal particles (commonly silver or gold) that support collective electron oscillations, enhancing local electromagnetic fields.

Hotspot: A nanoscale region of strongly intensified electromagnetic field at the junction of metal nanostructures, crucial for high SERS sensitivity.

Enhancement Factor: A quantitative measure of the increase in Raman signal intensity due to the SERS effect, often exceeding 10^6.

Limit of Detection (LOD): The lowest concentration of an analyte that can be reliably distinguished from background noise in a SERS measurement.

References

1. Office paper decorated with silver nanostars - an alternative cost effective platform for trace analyte detection by SERS. Scientific Reports (2017).
2. Highly sensitive plasmonic paper substrate fabricated via amphiphilic polymer self-assembly in microdroplet for detection of emerging pharmaceutical pollutants. Nano Convergence (2024).
3. Optimization of Paper-Based Alveolar-Mimicking SERS Sensor for High-Sensitivity Detection of Antifungal Agent. Biosensors (2024).
4. Chitosan coated papers as sustainable platforms for the development of surface-enhanced Raman scattering hydrophobic substrates. Journal of Molecular Liquids (2023).