Rapid polyelectrolyte-based membrane immunoassay for the herbicide butachlor

Area of Science:

• Environmental Science
• Analytical Chemistry
• Biotechnology

Background:

• Herbicide contamination in water poses environmental and health risks.
• Sensitive and rapid detection methods for herbicides like butachlor are crucial for water quality monitoring.
• Existing methods may be time-consuming or require specialized laboratory equipment.

Purpose of the Study:

• To develop a rapid and sensitive membrane immunoenzyme assay for the detection of the herbicide butachlor.
• To utilize oppositely charged water-soluble polyelectrolytes for efficient separation of immunoreactants.
• To enable out-of-laboratory testing for butachlor in various water samples.

Main Methods:

• Development of a competitive immunoassay format using peroxidase-labeled antigen.
• Application of high-affinity binding between polymethacrylate (polyanion) and poly(N-ethyl-4-vinylpyridinium) (polycation) for separation.
• Reflectometric detection of the insoluble colored product from the peroxidase reaction.
• Utilizing image processing algorithms for quantitative herbicide determination.

Main Results:

• The developed assay provides a short assay duration of 15 minutes.
• High sensitivity was achieved, with a detection limit of 0.03 µg/mL.
• Low variation coefficients (4.8-9.0%) were observed for antigen concentrations ranging from 0.1 to 3.0 ng/mL.
• The assay demonstrated effectiveness in controlling butachlor content in mineral, artesian, and drinking water.

Conclusions:

• The developed membrane immunoenzyme assay is effective for rapid, sensitive, and quantitative detection of butachlor.
• The use of oppositely charged polyelectrolytes facilitates efficient separation and enhances assay performance.
• This method is suitable for out-of-laboratory testing and monitoring of butachlor contamination in various water types.