A novel ultrasensitive surface plasmon resonance-based nanosensor for nitrite detection

Area of Science:

• Analytical Chemistry
• Nanotechnology
• Food Safety

Background:

• Nitrite is a common food additive, but its byproduct, nitrosamine, is a potent carcinogen.
• Ultra-sensitive nitrite detection is crucial for preventing nitrite-induced cancers.

Purpose of the Study:

• To develop a highly sensitive and selective nanosensor for detecting nitrite in food.
• To establish a colorimetric method for visual nitrite quantification.

Main Methods:

• Gold nanoparticles (AuNPs) were functionalized with p-aminothiophenol (ATP) and naphthylethylenediamine (NED).
• Nitrite triggers diazotization coupling, forming satellite-like AuNPs aggregates.
• Color changes in the AuNPs system indicate nitrite presence and concentration.

Main Results:

• The nanosensor demonstrated a linear concentration range of 0-1.0 μg mL⁻¹ for sodium nitrite.
• A low detection limit of 3.0 ng mL⁻¹ was achieved, significantly enhancing naked-eye detection.
• The method showed high sensitivity, selectivity, and suitability for various food matrices.

Conclusions:

• The developed AuNPs-based nanosensor provides a novel, highly sensitive method for nitrite determination.
• This technology offers significant potential for food safety applications and cancer prevention.
• The sensor's low detection limit and visual readout present market advantages.