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A competitive enzyme immunoassay for the quantification of polychlorinated biphenyls (PCBs) in soil and water was developed utilizing amine-terminated superparamagnetic particles as the solid phase. Aroclor 1254 was covalently attached to a bovine serum albumin carrier, and the resulting PCB−protein conjugate was used to immunize rabbits and to produce polyclonal antibodies with reactivity to a broad range of PCBs. Specificity studies indicate that the polyclonal antibody can detect Aroclors 1016, 1232, 1242, 1248, 1254, 1260, 1262, and 1268. The immunoassay has a estimated detection limit of 0.2 ppb (ng/mL) in water and 0.5 ppm (mg/kg) in soil based on Aroclor 1254. The assay compares favorably to GC method 8080 results when soil (r = 0.960) or water samples are evaluated (r = 0.909). The typical within assay % CV is less than 9% in water samples, and recovery studies averaged 99% in water and 85% in soil using a 1-min extraction. This immunochemical method provides quantitative field or laboratory screening results for characterizing and delineating PCB-contaminated sites.

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A competitive enzyme immunoassay for the quantitation of chlorpyrifos in water that utilizes amine-terminated superparamagnetic particles as the solid phase to covalently attach mouse monoclonal anti-chlorpyrifos antibodies was developed. Specificity studies indicate that the monoclonal antibody can distinguish chlorpyrifos from its major degradation products, including 3,5,6-trichloro-2-pyridinol, and structurally similar pesticides. The immunoassay has an estimated limit of detection of 0.10 ng/mL in water and compares favorably with traditional chromatographic methods when water samples are analyzed by both methods (r = 0.985). Within- and between-assay percent coefficient of variation values are <13%, and recovery of chlorpyrifos from water averaged 97% across the range of the immunoassay method. Keywords: Chlorpyrifos; immunoassay; ELISA; organophosphate; monoclonal antibody; insecticide; water