A quantitative enzyme-linked immunoassay for the detection of 2, 6-dichlorobenzamide (BAM), a degradation product of the herbicide dichlobenil.
2,6-Dichlorobenzamide (BAM) is the dominant degradation product in soil of the widely used herbicide dichlobenil. To detect BAM in water, a highly sensitive and specific enzyme-linked immunosorbent assay (ELISA) was developed. As an alternative to conventional coating of ELISA plates, the assay is based on direct covalent immobilisation. We achieved a surface which requires a short time for the immobilisation of ligand, is stable under dry storage, and which permits assays with a low CV. The performance of the assay was demonstrated by an inter-well CV that was generally less than 6%, a detection limit (DL(15)) of 0.02 microg/l and an IC(50) of 0.19 microg/l. Cross-reactivity was measured against nine analytes with structural homology to BAM. The highest degree of cross-reactivity (10.8%) was seen with 2,6-dichlorothiobenzamide (Chlorthiamid). Considering an EU-limit of 0.1 microg/l as the permissible maximum for the presence of pesticides in drinking water, this ELISA-procedure is suitable for large-scale screening of water samples suspected of being contaminated with BAM.
Bruun
L
L
Department of Geochemistry, Geological Survey of Denmark and Greenland, Copenhagen. lbr@geus.dk
Koch
C
C
Pedersen
B
B
Jakobsen
M H
MH
Aamand
J
J
D000818:Animals; D000911:Antibodies, Monoclonal; D000918:Antibody Specificity; D001549:Benzamides / Q000032:analysis* / Q000276:immunology; D001673:Biodegradation, Environmental; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006540:Herbicides / Q000378:metabolism*; D051379:Mice; D009570:Nitriles / Q000378:metabolism*; D012680:Sensitivity and Specificity; D013854:Thioamides / Q000276:immunology; D014874:Water Pollutants, Chemical / Q000032:analysis*
D000911:Antibodies, Monoclonal; D001549:Benzamides; D006540:Herbicides; D009570:Nitriles; D013854:Thioamides; D014874:Water Pollutants, Chemical; C058670:2,6-dichlorothiobenzamide; C055869:dichlobanil