Nitrite Determination in Environmental Water Samples Using Microchip Electrophoresis Coupled with Amperometric...

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Electrochemistry

Background:

• Nitrite is a key environmental analyte originating from the nitrogen cycle and pesticide leaching.
• Elevated nitrite levels in water pose risks, including human intoxication and metabolic disorders.

Purpose of the Study:

• To develop a portable analytical method for determining nitrite in environmental water samples.
• To couple microchip electrophoresis with amperometric detection for sensitive nitrite quantification.

Main Methods:

• Optimization of electrophoretic and amperometric detection conditions for microchip electrophoresis.
• Utilized a running buffer of lactic acid and histidine (pH 3.8) with a working electrode potential of 0.7 V.
• Amperometric detection was employed for quantitative nitrite measurements.

Main Results:

• Achieved rapid nitrite separation within 60 seconds.
• Demonstrated a wide linear range (20-80 μmol L⁻¹) with excellent linearity (R² = 0.999).
• Established a low limit of detection at 1.3 μmol L⁻¹ and validated results against a reference technique with good recovery (83.5-103.8%).

Conclusions:

• The developed portable microchip electrophoresis method is a sensitive, rapid, and simple tool for environmental nitrite monitoring.
• The methodology's low sample consumption and portability make it suitable for field applications.
• This technique provides a promising strategy for quantitative nitrite determination in environmental water samples.