Development of an enzyme-linked immunosorbent assay for cyhalothrin

Area of Science:

• Agricultural Chemistry
• Immunology
• Analytical Chemistry

Background:

• Cyhalothrin is a widely used synthetic pyrethroid insecticide.
• Accurate detection of cyhalothrin in environmental samples is crucial for monitoring and risk assessment.

Purpose of the Study:

• To develop and validate a specific and sensitive enzyme-linked immunosorbent assay (ELISA) for the detection of cyhalothrin.
• To prepare a specific monoclonal antibody against cyhalothrin.
• To establish an efficient method for cyhalothrin analysis in water samples.

Main Methods:

• Preparation of a specific monoclonal antibody against cyhalothrin using hapten immunization.
• Synthesis of a key intermediate (3-cyano-[...]-phenoxybenzyl propanoic acid) with a 35.9% yield.
• Establishment and optimization of a heterologous indirect ELISA by adjusting parameters like coating antigens, blocking agents, ionic strength, pH, and methanol concentration.
• Validation of the ELISA using spiked river, tap, and drinking water samples at various concentrations (0.2, 1.0, 5.0 mg/L).

Main Results:

• A specific monoclonal antibody with <5% cross-reactivity to analogues was obtained.
• The optimized ELISA demonstrated a 50% inhibition concentration (IC50) of 13.26 ± 1.23 ng/mL.
• Mean recoveries in spiked water samples ranged from 75.4% to 97.7%, with coefficients of variation between 5.1% and 11.6%.

Conclusions:

• The developed heterologous indirect ELISA is a potent and reliable method for the quantitative analysis of cyhalothrin.
• The assay exhibits high sensitivity and accuracy, suitable for detecting cyhalothrin in various water matrices.
• This immunoassay provides a valuable tool for environmental monitoring of cyhalothrin contamination.