A highly sensitive SERS sensor for malachite green detection based on spiky Fe₃O₄@Au supraparticles

Area of Science:

• Analytical Chemistry
• Materials Science
• Spectroscopy

Background:

• Malachite green (MG) is a synthetic dye with potential toxicity, necessitating reliable detection methods.
• Current detection methods for MG can be time-consuming and costly.
• There is a need for sensitive and specific analytical strategies for MG monitoring in food safety.

Purpose of the Study:

• To develop a novel, label-free analytical strategy for detecting malachite green (MG).
• To utilize spiky Fe3O4@Au supraparticles (Fe3O4@AuSPs) as both concentrating probes and SERS-active substrates.
• To achieve dual-signal amplification for enhanced detection sensitivity.

Main Methods:

• Development of spiky Fe3O4@Au supraparticles (Fe3O4@AuSPs) with built-in hotspots and magnetic properties.
• Utilizing surface-enhanced Raman spectroscopy (SERS) for label-free MG detection.
• Optimizing reaction conditions to achieve high sensitivity and specificity.

Main Results:

• The Fe3O4@AuSPs demonstrated dual-signal amplification through "built-in hotspots" and magnetic aggregation.
• Achieved a low limit of detection (LOD) of 10⁻¹² M for MG.
• Demonstrated high specificity and successful application in real samples (aquaculture water, fish, prawns, crabs).

Conclusions:

• The developed SERS-based strategy provides a practical and efficient approach for MG detection.
• This method significantly reduces detection time and cost for MG monitoring.
• The strategy shows strong potential for application in food safety surveillance of aquatic products.