Quantification of 2,4,5-trichlorophenoxyacetic acid by fluorescence enzyme-linked immunosorbent assay with secondary antibody

This paper describes a fluorescence enzyme-linked immunosorbent assay (ELIS A) for the quantification of 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) wi th an anti-rabbit secondary antibody conjugated to peroxidase (goat anti-ra bbit IgG HRP) for sandwich antibody assay. Human gamma globulin (HGG) conju gated to 2,4,5-T was readily coated on a polystyrene microplate. Data acqui sition on microtiter wells is performed by a spectrofluorimeter through a f ibre optic. The standard curve was produced for 0.01-5000 ng ml(-1) 2,4,5-T . The minimum detectable concentration was 0.023 ng ml(-1) and the relative standard deviation was 6.9% for a 5 ng ml(-1) sample (n=10). The ELISA pro cedure was selective with respect to structurally similar compounds usually found in pesticide formulations. This method was applied to 2,4,5-T previo usly added to apple juice. (C) 1999 Elsevier Science B.V. All rights reserv ed.