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PubMed · 11563654

Screening method for nitroaromatic compounds in water based on solid-phase microextraction and infrared spectroscopy.

D C Stahl·D C Tilotta
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Abstract

A new method is described for determining nitroaromatic compounds in water that combines solid-phase microextraction (SPME) and infrared (IR) spectroscopy. In this method, the compounds are extracted from a 250-mL volume of water into a small square (3.2 cm x 3.2 cm x 61.2 microm thick) of silicone polycarbonate copolymer film (MEM-213). Five nitroaromatic compounds, including 2,4,6-trinitrotoluene (TNT), were chosen to evaluate the SPME/IR procedure. Quantitation limits for the five test compounds range from 50 microg/L for TNT to 400 microg/L for nitrobenzene. Precision values, determined at aqueous concentrations of four times the quantitation limit, range from 4 to 7%, and linear dynamic ranges extend to the maximum limit of the IR instrumentation. The potential of this SPME/IR method for determining nitroaromatics in natural water samples was also investigated by extracting "real world" soil samples contaminated with TNT. Results obtained from the SPME/ IR determination of the diluted extracts were in reasonable agreement with those obtained from dichloromethane extraction followed by gas chromatographic analysis.

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Chromatography, GasEnvironmental MonitoringHydrocarbons, AromaticNitrogen CompoundsReproducibility of ResultsSpectrophotometry, InfraredWater Pollutants, ChemicalJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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D C Stahl, D C Tilotta. 2001-09-01. Screening method for nitroaromatic compounds in water based on solid-phase microextraction and infrared spectroscopy.. https://doi.org/10.1021/es010550c

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