Determination of dibutyl o-phthalate by antigen-coated competitive fluorescence immunoassay

A reliable and sensitive competitive fluorescence immunoassay for the quantitative determination of dibutyl phthalate (DBP) was developed. The hapten of dibutyl phthalate was synthesized. The hapten-protein conjugate was used as an immunogen, demonstrating that it is suitable for polyclonal antibody production. With this polyclonal antibody, a novel fluorescence immunoassay for detection of DBP was described. Under best conditions, DBP can be determined in the concentration range of 0.1 similar to 100 mu g/L with a detection limit of 0.05 mu g/L. The cross-reactivities of the anti-DBP antibody to six structurally related phthalate esters were below 9%. Some environmental samples were analyzed with satisfactory results.