Application of ELISA techniques to metabolic disposition studies for 1,3-dinitrobenzene: Comparison with HPLC and radiochemical methods

An enzyme-linked immunosorbent assay (ELISA) is reported for the detection and quantitation of 1,3-dinitrobenzene, a widely used chemical intermediate in industrial syntheses and potent testicular toxicant in rats. Radiolabeled [¹⁴C]-1,3-dinitrobenzene (25 mg/kg, ip) was administered to rats, and the blood disappearance curve generated with the ELISA assay was compared with HPLC separation and quantitation by using both UV and radiochemical methods. An excellent correlation was found between the two methods. Matrix effects from the blood samples were minimal. Cross reactivity with metabolites of 1,3-dinitrobenzene occurred only at levels that were 3 orders of magnitude greater than for the parent compound. The specificity of the ELISA for 1,3-dinitrobenzene was further demonstrated with a variety of other nitroaromatic compounds, of which only 2,4-dinitrotoluene showed significant cross reactivity. The sensitivity and specificity of the 1,3-dinitrobenzene ELISA demonstrate the usefulness of an approach which, if verified with conventional analytical methods, allows rapid and inexpensive measurement of xenobiotic levels in biological samples.