title: Enzyme-linked immunosorbent assays based on rabbit polyclonal and rat monoclonal antibodies against isoproturon.
abstract: This work describes the production and characterization of rabbit polyclonal antisera (pAb) and rat monoclonal antibodies (mAb) against isoproturon. Coating antigen and enzyme-tracer formats were developed. Standard curves for isoproturon were conducted either in 40 mM phosphate buffered saline (PBS) or in Milli-Q water. PAb 352 together with the best enzyme tracer revealed in the optimized ELISA (enzyme tracer format) a test midpoint of 1.06 +/- 0.34 microg/L (n = 19, standard set up in Milli-Q water) with a detection limit of about 0.1 microg/L. The comparable ELISA with mAb IOC 7E1 had test midpoints of 0.07 +/- 0.04 microg/L (n = 7, standards in Milli-Q water) and 0.11 +/- 0.08 microg/L (n = 33; standards in 40 mM PBS). The limits of detection were about 0.003 and 0.01 microg/L in Milli-Q water and PBS, respectively. Noticeable cross reactivities (CRs) were seen with the major metabolites, namely 4-isopropylaniline, 4-isopropylphenylurea, and 1-(4-isopropylphenyl)-3-methylurea. With pAb 352, these CRs were 5%, 7%, and 31%, respectively, and with mAb IOC 7E1, they were 3%, 5%, and ca. 19%, respectively. All arylurea herbicides had only minor CRs, which ranged from no CR (e.g., chlorosulfuron) to a maximum of 3.3% (chlortoluron). Influences of organic solvents (methanol, ethanol, acetonitrile, and acetone) were evaluated. Both pAb- and mAb-based immunoassays showed the highest tolerance for methanol, up to 5%. Ethanol and acetonitrile could not be used above 2% without an influence on the assays. The same was true for acetone, although tested only in the mAb-based assay. Water samples of different origins and matrices were spiked and analyzed with these pAb and mAb ELISAs. The results demonstrated that these immunoassays are useful screening tools.
authors.affiliation: Technische Universität München, Wissenschaftszentrum Weihenstephan, Lehrstuhl für Okologische Chemie und Umweltanalytik, Weihenstephaner Steig 23, D-85350 Freising, Germany. kramer@gsf.de
authors.forename: Petra M
authors.initials: PM
authors.lastname: Krämer
authors.forename: Marvin H
authors.initials: MH
authors.lastname: Goodrow
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Kremmer
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis; D000918:Antibody Specificity; D000941:Antigens / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006241:Haptens; D006540:Herbicides / Q000032:analysis*; D007106:Immune Sera / Q000096:biosynthesis; D007202:Indicators and Reagents; D008782:Methylurea Compounds / Q000032:analysis* / Q000276:immunology*; D010671:Phenylurea Compounds; D011817:Rabbits; D051381:Rats
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens; D006241:Haptens; D006540:Herbicides; D007106:Immune Sera; D007202:Indicators and Reagents; D008782:Methylurea Compounds; D010671:Phenylurea Compounds; C028904:isoproturon