Place & Play SERS: sample collection and preparation-free surface-enhanced Raman spectroscopy

Area of Science:

• Analytical Chemistry
• Materials Science
• Spectroscopy

Background:

• Sensitive, real-time, in situ chemical analysis is crucial for various fields, including health, food safety, forensics, and environmental monitoring.
• Surface-enhanced Raman spectroscopy (SERS) offers high sensitivity and rapid, label-free detection, but its practical use is hindered by sample collection and preparation requirements.
• Traditional SERS necessitates touching, destroying, or sampling analytes, limiting its application in scenarios where such procedures are difficult, dangerous, or undesirable.

Purpose of the Study:

• To develop a novel SERS measurement scheme that bypasses the need for sample collection and preparation.
• To introduce a flexible, adhesive, and biointegratable gold-deposited polyvinyl alcohol (PVA) nanomesh substrate for direct in situ SERS analysis.
• To demonstrate the practical utility of this new 'Place & Play SERS' approach in real-world applications.

Main Methods:

• Fabrication of an ultrathin, flexible, stretchable, and adhesive gold-deposited PVA nanomesh substrate.
• Characterization of the substrate's sensitivity using the 'Place & Play SERS' measurement scheme with epi-excitation.
• Application of the 'Place & Play SERS' method for analyzing both wet and dry objects under realistic conditions, including food safety and forensic scenarios.

Main Results:

• The gold/PVA nanomesh substrate demonstrated effective sensitivity in the 'Place & Play SERS' configuration.
• Successful in situ SERS measurements were performed on various objects without direct contact or sample manipulation.
• The 'Place & Play SERS' scheme was validated through practical demonstrations in food safety testing and forensic analysis.

Conclusions:

• The 'Place & Play SERS' method, utilizing a novel gold/PVA nanomesh substrate, offers a significant advancement over traditional SERS techniques.
• This approach enables sensitive, real-time, in situ, and multiplex chemical analysis without sample collection or preparation.
• The findings are expected to expand the applicability of SERS into new domains and enhance its utility in diverse scientific and security fields.