Evaluation of ELISA kits followed by liquid chromatography atmospheric pressure chemical ionization mass spectrometry for the determination of organic pollutants in industrial effluents

Contaminated industrial effluents often contain a variety of organic pollutants which are difficult to analyze by standard GC-MS methods since they often miss the more polar or nonvolatile of these organic compounds. The identification of highly polar analytes by chemical or rapid biological techniques is needed for characterization of the effluents. The present work will evaluate the use of enzyme linked immunosorbent assays (ELISA) kits for determining pentachlorophenol, carcinogenic PAHs and BTEX (benzene, toluene, ethylbenzene, and o-, m-, and p-xylene) among the organic analytes present in various industrial effluents from Europe (petrochemical plant and hazardous waste). The analytical protocol applied for the evaluation of the kits was based on the use of ELISA followed by solid-phase extraction (SPE) for the preconcentration of a variety of organic pollutants such as pentachlorophenol, phthalates, and nonylphenol and final determination with LC-MS characterization using an atmospheric pressure chemical ionization (APCI) interface in the positive and negative ionization modes. The developed protocol permitted the unequivocal identification of target analytes such as pentachlorophenol, nonylphenol, dibutylphthalate, dimethylphthalate, bis(2-ethylhexyl)phthalate, 2-mettlylbenzenesulfonamide, and 2,2-dimethylbenzene-sulfonamide present in industrial effluents. The advantages and limitations of the three RaPID-magnetic particle-based ELISA kits applied to the characterization of industrial effluents are also reported.