Wide-Field Digital Surface-Enhanced Raman Scattering: Quantitative Single-Molecule Detection with High Sensitivity...

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Nanotechnology

Background:

• Surface-Enhanced Raman Scattering (SERS) offers high sensitivity and specificity for diverse applications.
• Quantitative SERS detection is limited by substrate non-uniformity and poor reproducibility, especially at low concentrations.
• Digitization of SERS signals has shown promise for sensitive and quantitative detection.

Purpose of the Study:

• To develop an advanced Wide-field Digital SERS (WidiSERS) platform for high-throughput, reproducible, and ultrasensitive quantitative detection.
• To address the limitations of traditional SERS in terms of reproducibility and quantification at low analyte levels.
• To demonstrate the practical applicability of WidiSERS for trace-level analysis in complex real-world samples.

Main Methods:

• Utilized wide-field microscopy for high-throughput SERS measurements.
• Employed protein-assembled gold nanorod dimers as substrates to significantly enhance Raman signals.
• Achieved single-molecule measurements for reproducible quantification of various target molecules.
• Validated the method by quantifying ciprofloxacin in milk and phenylalanine in cell culture medium.

Main Results:

• Developed a WidiSERS system enabling reproducible quantification of diverse molecules at extremely low concentrations.
• Demonstrated successful trace-level quantification of ciprofloxacin in milk and phenylalanine in cell culture medium.
• Showcased the practicability and accuracy of the WidiSERS method in complex biological and environmental matrices.
• The gold nanorod dimer substrates proved to be easily prepared and reusable after UV/ozone cleaning.

Conclusions:

• WidiSERS offers a robust solution for reproducible and ultrasensitive quantitative detection, overcoming key limitations of conventional SERS.
• The developed platform is highly effective for trace-level analysis in complex samples, highlighting its potential for diverse applications.
• The reusable and easily prepared gold nanorod dimer substrates contribute to the practicality and cost-effectiveness of the WidiSERS method.
• WidiSERS is poised to become a preferred technique for ultrafast and effective detection across various scientific and industrial fields.