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.