Analysis of hexazinone in soil by enzyme-linked immunosorbent assay

A tube enzyme immunoassay (EIA) procedure was developed for the determination of the triazine herbicide hexazinone in soil The antibody was polyclonal and was prepared by employing metabolite A of hexazinone conjugated to bovine serum albumin as the immunogen. Hexazinone was extracted from soil by shaking with methanol-water 80/20 for 10 min and allowed to set overnight before reshaking for 5 min. Aliquots for EIA analysis were diluted in such a way as to always contain 8% methanol Reproducibility results for both standards and samples were good. A correlation coefficient of 0.9562 was obtained for 78 soil samples analyzed by EIA vs. HPLC. Of the eight known metabolites of hexazinone, 7 were tested for cross-reactivity and 5 were shown to be cross-reactive.