Ultrasensitive SERS Detection of Five β-Blockers Achieved Using Chemometrics with a Two-Dimensional Substrate Formed...

Area of Science:

• Analytical Chemistry
• Materials Science
• Spectroscopy

Background:

• Beta-blockers (β-blockers) are crucial pharmaceuticals, but their illicit use necessitates sensitive detection methods.
• Existing detection methods may lack the speed and portability for on-site screening.

Purpose of the Study:

• To develop a surface-enhanced Raman scattering (SERS) platform for the rapid and sensitive detection of five specific beta-blockers (β-blockers).
• To evaluate the platform's performance in complex matrices like human urine and its potential for antidoping applications.

Main Methods:

• Fabrication of a two-dimensional substrate using self-assembled large silver-core silica-shell nanoparticles (Ag@SiO₂ NPs) on a silicon wafer.
• Utilizing the enhanced electromagnetic field generated by the nanoparticle arrangement for SERS measurements.
• Applying portable Raman spectroscopy for on-site analysis and chemometric methods (PCA, HCA) for spectral differentiation.

Main Results:

• The SERS platform demonstrated linear responses for five β-blockers (atenolol, esmolol, labetalol, sotalol, propranolol) in the concentration range of 10^-5 to 10^-8 mol/L.
• Achieved low detection limits, down to 10^-10 mol/L for propranolol.
• Quantitative recovery (93-101%) was observed for β-blockers spiked in human urine samples.
• Principal component analysis (PCA) and hierarchical cluster analysis (HCA) effectively differentiated between the five β-blockers based on their SERS spectra.

Conclusions:

• The developed Ag@SiO₂ NP-based SERS platform offers high sensitivity and specificity for detecting multiple β-blockers.
• The platform's portability and quantitative accuracy in urine samples highlight its potential for rapid, on-site drug detection and antidoping screening.