Bimetallic AuPt nanoparticles-based SERS substrate for high-performance endosulfan detection

Area of Science:

• Materials Science
• Analytical Chemistry
• Nanotechnology

Background:

• Surface-enhanced Raman spectroscopy (SERS) is crucial for trace pesticide detection in food and environmental samples.
• Detecting the hazardous organochlorine pesticide endosulfan (ES) at low concentrations remains challenging due to its stability.

Purpose of the Study:

• To develop a novel SERS substrate for sensitive and rapid detection of endosulfan (ES).
• To investigate the potential of bimetallic gold-platinum nanoparticles (AuPt NPs) as an effective SERS platform.

Main Methods:

• Bimetallic AuPt nanoparticles (NPs) were synthesized via precursor reduction.
• Nanomaterials were characterized using TEM, HRTEM, XRD, EDS, and UV-vis spectroscopy.
• SERS performance was evaluated using endosulfan as the probe analyte.

Main Results:

• AuPt NPs with a 1:1 Au:Pt molar ratio demonstrated optimal SERS performance.
• An enhancement factor (EF) of ~14.3 × 10^6 and a limit of detection (LOD) of 0.05 ppm for endosulfan were achieved.
• The substrate exhibited good repeatability, signal uniformity, and storage stability.

Conclusions:

• The enhanced SERS performance is attributed to the synergistic effects of alloy composition, nanoparticle morphology, and hotspot generation.
• Electromagnetic enhancement is the dominant mechanism, supported by electronic interactions between AuPt NPs and endosulfan molecules.
• AuPt NPs represent a promising SERS-active platform for sensitive endosulfan detection.