Development of an enzyme immunoassay for the determination of the herbicide metsulfuron-methyl based on chicken egg yolk antibodies

The development of an indirect competitive enzyme immunoassay for the sulfo nylurea herbicide metsulfuron-methyl (MSM) is described. In contrast to tra ditional antibody generation in mammals, this extremely sensitive method is based on chicken egg yolk antibodies (IgY). They were raised in laying hen s using an MSM-derivative-BSA hapten as immunogen. With a 1:10000 dilution of the antibody solution and a coating antigen (MSM-derivative-KLH) concent ration of 10 mug L-1 the IC50 value achieved for the target analyte was 0.4 mug L-1. The least detectable dose was established at 13 ng L-1. Cross-rea ctivity was tested with 5 structurally related compounds, where only sulfom eturon showed a significant binding. The ELISA was tested with spiked tap a nd surface water samples. This paper, for the first time, demonstrates the production of high-affinity IgY antibodies for a herbicide compound.