A nonenzymatic reduced graphene oxide-based nanosensor for parathion

Area of Science:

• Analytical Chemistry
• Materials Science
• Environmental Science

Background:

• Organophosphate pesticides (e.g., parathion) pose risks to human health via residues in food and the environment.
• Current detection methods require improvement in cost-effectiveness and speed.
• Rapid, sensitive, and reliable detection strategies are crucial for ensuring food safety and environmental protection.

Purpose of the Study:

• To develop a robust, nonenzymatic electrochemical sensor for detecting organophosphate pesticide residues.
• To utilize electrochemically reduced graphene oxide (ERGO) for enhanced sensor performance.
• To enable rapid, cost-effective, and sensitive quantification of parathion (PT) in various samples.

Main Methods:

• Fabrication of an electrochemical sensor electrode modified with ERGO.
• Electrochemical characterization and optimization of the ERGO sensor.
• Quantification of PT using square-wave voltammetry.
• Validation of sensor performance using natural samples and absorption spectroscopy.

Main Results:

• The ERGO sensor exhibited a distinct electrocatalytic reduction peak for PT at -0.58 V (vs Ag/AgCl).
• Achieved high sensitivity (50.5 μA·μM^-1·cm^-2), selectivity, and stability (≈180 days).
• Demonstrated a low detection limit of 10.9 pM within a wide dynamic range (3 × 10^-11-11 × 10^-6 M).

Conclusions:

• The developed ERGO-based electrochemical nanosensor provides a highly sensitive and stable platform for PT detection.
• The sensor is suitable for point-of-care applications and interference-free analysis in real-world samples.
• This work encourages the development of similar nanosensor-based tools for monitoring other environmental contaminants.