Enzyme-linked immunoassay for the detection of glyphosate in food samples using avian antibodies

A simple competitive immunoassay was developed for the measurement of glyphosate in food samples. It employed the avian antibodies (IgY) that recognised glyphosate as a capture reagent and glyphosate-alkaline phosphatase conjugate as an enzyme label. The assay depended on the competitive binding between the antibody and glyphosate derived from food samples for binding sites with immobilised glyphosate-OVA conjugate. The concentration of glyphosate in the food samples was quantified by the ability of the pesticide present in food samples to inhibit the binding of the enzyme conjugate to the antibody and subsequently the colour formation in the assay. The assay was specific to glyphosate with a limit of detection of 2 ppb. Mean analytical recovery of glyphosate in different food samples was 9.00-134.00%. The precision of the assay was satisfactory. The assay compared favourably with high-pressure liquid chromatography (HPLC) in its ability to accurately measure glyphosate in the food samples.