Flow-through photometric sensor for determination of sulfonamides

Area of Science:

• Analytical Chemistry
• Chemical Sensors
• Spectrophotometry

Background:

• Sulfonamides are widely used antimicrobials, necessitating reliable detection methods in various matrices.
• Existing automated and non-automated methods for sulfonamide determination can be limited by sensitivity or complexity.
• The Bratton-Marshall reaction is a common colorimetric method for sulfonamide analysis.

Purpose of the Study:

• To develop and validate a novel sensor for the determination of four key sulfonamides.
• To enhance analytical sensitivity and efficiency in sulfonamide detection.
• To apply the developed method for analyzing sulfonamides in real-world samples like milk and water.

Main Methods:

• Integration of spectrophotometric detection with product retention within a flow injection manifold.
• Utilized the Bratton-Marshall reaction for colorimetric product formation.
• Employed in situ concentration for enhanced analyte levels prior to detection.

Main Results:

• Achieved linear detection ranges for sulfanilamide, sulfamethazine, sulfaquinoxaline, and sulfathiazole from 10 to 1200 ng/mL.
• Demonstrated high precision with relative standard deviations consistently below 2.6%.
• Successfully applied the sensor to determine sulfonamides in spiked milk and water samples, yielding excellent results.

Conclusions:

• The developed sensor offers enhanced sensitivity for sulfonamide determination due to in situ concentration.
• The method avoids the need for a de-bubbler, simplifying the flow system by eliminating nitrogen gas interference.
• This sensor-based approach provides a sensitive, precise, and efficient alternative for sulfonamide analysis in complex matrices.