The Trace Detection of Nitrite Ions Using Neutral Red Functionalized SH-β-Cyclodextrin @Au Nanoparticles

Area of Science:

• Nanomaterials Science
• Analytical Chemistry
• Environmental Science

Background:

• Nitrite detection is crucial for environmental monitoring and food safety.
• Existing methods for nitrite detection can be complex or lack sensitivity.
• Gold nanoparticles (AuNPs) offer unique optical properties for sensor development.

Purpose of the Study:

• To develop a novel and sensitive fluorescence sensor for trace nitrite detection.
• To utilize host-guest inclusion complexes for enhanced sensing capabilities.
• To apply the sensor for analyzing nitrite in real-world environmental water samples.

Main Methods:

• Preparation of neutral red (NR) and beta-cyclodextrin-modified gold nanoparticles (β-CD@AuNPs) via microwave-assisted synthesis.
• Utilizing the fluorescence quenching mechanism of NR-β-CD@AuNPs in response to nitrite ions.
• Characterization of the sensor's performance, including sensitivity and limit of detection.
• Application of the sensor for the quantitative determination of nitrite in environmental water samples.

Main Results:

• A novel NR-β-CD@AuNPs fluorescence sensor was successfully synthesized.
• The sensor demonstrated high sensitivity for trace nitrite detection, with a limit of detection as low as 4.25 × 10^-3 μg∙mL^-1.
• A distinct color change was observed in the presence of nitrite ions, indicating a visual detection capability.
• The sensor provided satisfactory results when applied to the determination of trace nitrites in environmental water samples.

Conclusions:

• The developed NR-β-CD@AuNPs sensor is a promising tool for sensitive and reliable trace nitrite detection.
• The sensor's ability to function in aqueous media and its satisfactory performance in real samples highlight its practical applicability.
• This work contributes to the advancement of nanomaterial-based sensors for environmental analysis.