Isomer and congener identification of chlorinated pyrenes by narrow-bore liquid chromatography—Fourier transform infrared spectrometry

Liquid chromatography (LC) was coupled semi on-line to Fourier transform infrared spectrometry (FT-IR) using a spray-jet assembly interface to eliminate the LC eluent prior to IR detection. The usefulness of the LC-FT-IR system in the identification of closely related compounds in complex mixtures is demonstrated by the analysis of a chlorinated pyrene sample which contains a number of chloropyrene isomers and congeners. Characteristic FT-IR transmission spectra of all constituents could be recorded. Since most of these compounds have not been analysed by IR before, spectral assignment was mainly based on the empirical Hansen—Berg rules for substituted pyrenes. The identification limits for the chloropyrenes typically were 5–10 ng injected.