Robust and sensitive determination of nitrites in pickled food by surface-enhanced Raman spectroscopy

Area of Science:

• Analytical Chemistry
• Materials Science
• Food Science

Background:

• Nitrites in food are a significant health concern.
• Accurate and rapid detection of nitrites is crucial for food safety.
• Existing methods may lack sensitivity or speed for real-time monitoring.

Purpose of the Study:

• To develop a robust, rapid, and sensitive method for nitrite ion detection.
• To utilize gold-silver (Au@Ag) nanoparticles as a surface-enhanced Raman spectroscopy (SERS) substrate.
• To validate the method's performance in pickled food samples.

Main Methods:

• Fabrication of Au@Ag nanoparticles for SERS applications.
• Anchoring nitrite ions to the SERS substrate using 4-aminophenylthiophenol (PATP).
• Utilizing SERS for quantitative analysis with internal calibration by PATP.

Main Results:

• Established a linear relationship for nitrite detection (R² = 0.987) in the 5.00-100.00 μM range.
• Achieved a low limit of detection (LOD) of 0.17 μM for nitrites.
• Demonstrated high selectivity, good precision (RSD < 7.00%), and recovery rates (101.42-107.35%) in real samples.

Conclusions:

• The proposed SERS method offers a reliable and sensitive approach for nitrite determination in pickled foods.
• The use of Au@Ag nanoparticles enhances detection capabilities.
• This method holds significant potential for food safety and regulatory supervision.