Development of Robust, Environmental, Immunoassay Formats for the Quantification of Pesticides in Soil
文摘
The use of antibodies, or more specifically recombinantantibody fragments (scAbs), for the immunodetectionof pesticides, could provide a rapid, reliable, and robustmethod of environmental analysis. The inherent instabilityof some antibody structures in nonphysiological conditions,however, limits the utility of this approach. We have developeda generic strategy for the stabilization of scAbs in polarand nonpolar solvents, and in a range of other denaturingenvironments, by the introduction of an interdomaindisulfide bond, generating stabilized antibody fragmentsor stAbs. StAbs specific for the phenoxyacid herbicidemecoprop and the phenylurea herbicide diuron were fullyfunctional when compared to their equivalent unmodifiedscAbs but significantly more stable in nonphysiologicalconditions associated with the extraction of organics fromenvironmental samples. Antiatrazine, mecoprop, diuron,and paraquat stAbs were successfully used to accuratelyidentify and quantify pesticides present in solvent andaqueous extracted soil samples. Immunoassay data werevalidated by HPLC. Recombinant stAbs can be producedreadily, cost-effectively, and in quantity from Escherichia coliexpression systems and provide robust reagents forimmunoassay detection of pollutants present in complexenvironmental matrices.