Development of an Enzyme Linked Immunosorbent Assay for the Detection of Glyphosate in Water Samples Using Avian Antibodies.

A simple competitive immunoassay was developed for the measurement of glyphosate in water
samples. The assay employed the avian antibodies (lg¥) that recognized glyphosate as a capture reagent and
glyphosate - alkaline phosphatase conjugate as an enzyme label. The assay depended on the competitive
binding reaction between the antiglyphosate antibody and glyphosate derived from water samples for
binding sites with immobilized glyphosate-OVA conjugate. The concentration of glyphosate in the water
samples was quantified by the ability of the pesticide present in water 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 ng/ mL. Mean analytical recovery of glyphosate in
different water samples was 42.97 to 160.00%. The precision of the assay was satisfactory. Coefficients of
variation were 0.002 to 1.24 and 0.055 to 1.41% for intra and inter assay precision respectively. The assay
compared favourably with HPLC in its ability to accurately measure glyphosate in the water samples.