Highly Sensitive Graphene-Based Electrochemical Sensor for Nitrite Assay in Waters

Area of Science:

• Electrochemistry
• Materials Science
• Environmental Chemistry

Background:

• Nitrite ions are crucial in environmental and public health contexts.
• Increased exposure to nitrites from fertilizers and food additives raises health concerns.
• Sensitive detection methods for nitrites in water are essential.

Purpose of the Study:

• To develop a highly sensitive electrochemical sensor for trace nitrite detection.
• To utilize a graphene/glassy carbon electrode (EGr/GC) for enhanced nitrite sensing.
• To validate the sensor's performance in real-world water samples.

Main Methods:

• Fabrication of a graphene-modified glassy carbon electrode (EGr/GC).
• Structural characterization of the graphene material (GO, FLG, MLG).
• Electrochemical detection of nitrite using square wave voltammetry (SWV) and amperometry (AMP).

Main Results:

• The EGr/GC electrode showed a three-order-of-magnitude higher response to nitrite than the bare electrode.
• Linear detection ranges were established for SWV (3 × 10^-7 to 10^-3 M) and AMP (3 × 10^-7 to 4 × 10^-4 M).
• A low limit of detection (LOD) of 9.9 × 10^-8 M was achieved, with excellent stability and repeatability.

Conclusions:

• The developed EGr/GC sensor is effective for trace nitrite detection in water.
• The sensor exhibits superior performance compared to bare electrodes.
• The sensor demonstrates practical applicability and reliability for water quality monitoring.