Phenosafranin-Based Colorimetric-Sensing Platform for Nitrite Detection Enabled by Griess Assay

Area of Science:

• Analytical Chemistry
• Environmental Science

Background:

• Nitrite (NO2-) is an important analyte in various matrices, including food and environmental samples.
• Accurate detection of nitrite is crucial for food safety and environmental monitoring.
• Existing methods for nitrite detection can be complex or lack sensitivity.

Purpose of the Study:

• To develop a facile and effective colorimetric sensing platform for nitrite detection.
• To utilize the diazotization of phenosafranin for quantitative nitrite analysis.
• To validate the sensor's performance using the Griess assay under acidic conditions.

Main Methods:

• Diazotization of phenosafranin under acidic conditions to produce a color change.
• Colorimetric quantitative detection of nitrite (NO2-) based on the intensity of the blue color.
• Optimization of sensor parameters including phenosafranin concentration, HCl concentration, and reaction time.
• Validation of linearity, detection limit, reproducibility, and selectivity.

Main Results:

• The optimized sensor achieved a linearity range from 0 to 20 μM for nitrite detection.
• A low detection limit of 0.22 μM was achieved under optimal conditions.
• The sensing platform demonstrated favorable reproducibility and selectivity for nitrite.
• Successful application of the sensor to detect nitrite in spiked food samples (ham sausage, bacon, sprouts).

Conclusions:

• The developed phenosafranin-based colorimetric sensor provides a simple and effective method for nitrite detection.
• The sensor exhibits excellent performance characteristics, including sensitivity and selectivity.
• The platform shows great potential for practical applications in real-world nitrite analysis, particularly in food safety.