Semi-wrapped gold nanoparticles for surface-enhanced Raman scattering detection.

Area of Science:

• Nanomaterials Science
• Analytical Chemistry
• Spectroscopy

Background:

• Developing reliable and sensitive surface-enhanced Raman scattering (SERS) substrates for complex systems remains a challenge.
• Existing SERS substrates often face limitations in balancing signal reliability and sensitivity.

Purpose of the Study:

• To propose a novel SERS substrate strategy using gold cores with incompletely wrapped Prussian blue (PB) for enhanced reliability and sensitivity.
• To achieve a balance between signal self-calibration and enhancement for SERS detection.
• To demonstrate the practical application of the developed SERS substrate in detecting hazardous substances.

Main Methods:

• Construction of gold (Au) cores with approximately semi-wrapped Prussian blue (PB) layers (SW-Au@PB).
• Utilizing the internal standard (IS) capability of PB layers for SERS signal calibration.
• Employing exposed Au core surfaces for Raman signal enhancement.
• Testing the SW-Au@PB nanoparticles (NPs) with R6G as probe molecules to assess reliability and sensitivity.
• Applying the SW-Au@PB NPs for the detection of pesticide residues (paraquat and thiram) in herbal plants.

Main Results:

• The SW-Au@PB NPs demonstrated an enhancement factor comparable to pristine Au NPs.
• Achieved ultralow relative standard deviation (RSD) of 8.55% for calibrated SERS signals.
• Successfully enabled the detection of hazardous pesticide residues with an average accuracy of up to 92%.
• Validated the controllable synthesis strategy for incompletely wrapped nanoparticles.

Conclusions:

• The SW-Au@PB NPs offer a promising solution for achieving both high reliability and sensitivity in SERS detection.
• This approach provides a controllable synthetic strategy for novel nanoparticle architectures.
• The developed SERS substrate shows significant potential for accurate and sensitive detection of hazardous substances in practical applications.