Determination of 3,3′,4,4′-tetrachloroazobenzene in water by isotope dilution gas chromatography/high resolution mass spectrometry

A methodology, based on gas chromatography/high resolution mass spectrometry selected ion monitoring (GC/HRMS SIM) has been developed for the determination of 3,3′,4,4′-tetrachloro-azobenzene (TCAB), a potential carcinogen, in water. As internal standard we prepared [13C12] labelled TCAB, from [13C6] labelled benzene. TCAB was extracted from water by hexane followed by a cleanup column chromatography over basic alumina. Recoveries of TCAB range from 80.0 – 88.3 %. The detection limit of TCAB is about 50 fg of TCAB or 5 ppq in 1,000 mL of water.