A Pyrazoline-Based Fluorescent Sensor for Picric Acid Detection in Aqueous Media: Experimental and DFT Insights

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• Picric acid (PA) is a hazardous explosive and pollutant.
• Accurate detection of PA in aqueous environments is crucial for safety and environmental protection.
• Existing detection methods may lack sensitivity or practicality for real-world samples.

Purpose of the Study:

• To develop a novel pyrazoline-based fluorescence sensor (BTP) for the reliable identification of picric acid (PA).
• To evaluate the sensor's performance in various aqueous matrices.
• To elucidate the interaction mechanism between the sensor and picric acid.

Main Methods:

• Synthesis and characterization of the pyrazoline-based fluorescence sensor BTP.
• Fluorescence spectroscopy was used to detect picric acid.
• Evaluation of sensor performance including linear range and detection limit.
• Density Functional Theory (DFT) studies were performed to understand the interaction mechanism.

Main Results:

• The developed sensor BTP demonstrated reliable picric acid identification in aqueous environments.
• BTP showed a linear detection range from 0 to 10 µM with a detection limit of 0.991 µM.
• The sensor exhibited high quenching efficiency (75.12%) for picric acid compared to other nitroaromatics.
• DFT studies confirmed an electron transfer mechanism in the BTP-PA interaction.

Conclusions:

• The pyrazoline-based fluorescence sensor BTP is a sensitive and efficient tool for detecting picric acid in water.
• BTP's performance across different water types highlights its potential for environmental monitoring.
• The electron transfer mechanism provides insight into the sensor's sensing capabilities.