Liquid-chromatographic determination of halogenated bisphenols based on intramolecular excimer-forming fluorescence derivatization

Abstract

A selective determination method for halogenated bisphenols containing tetrabromobisphenol A has been developed. This method is based on an intramolecular excimer-forming fluorescence derivatization with a pyrene reagent, 4-(1-pyrene)butanoyl chloride (PBC), followed by reversed-phase chromatography (LC). Bisphenols, containing two phenolic hydroxyl groups in a molecule, were converted to the corresponding dipyrene-labeled derivatives by a reaction with PBC. These derivatives afforded intramolecular excimer fluorescence (440-540 nm), which could be clearly discriminated from the normal fluorescence (360-420 nm) emitted from PBC and monopyrene-labeled derivatives. The PBC derivatives could be separated by reversed-phase LC on an ODS column with isocratic elution using aqueous 99% (v/v) acetonitrile as a mobile phase. The detection limits (signal-to-noise ratio = 3) for halogenated bisphenols were femtomole levels for a 5 μl injection.