Increased sensitivity and selectivity of an enzyme-linked immunosorbent assay for the determination of atrazine by use of non-ionic surfactants

Different non-ionic detergents have been investigated for their use in a competitive enzymatic immunoassay for the determination of atrazine. Addition of surfactants enhances the activity of the horseradish peroxidase and modifies the selectivity by changing the cross-reactivity of other triazine herbicides. This allows a confirmation of the analyte identity without using different antibodies. If the addition of a surfactant leads to a different result in the analyte quantification, the presence of cross-reacting compounds is likely. In combination with the cloud point extraction the detection limit can be improved by a factor of ten (8 ng/l).