Liquid chromatographic determination of bisphenols based on intramolecular excimer-forming fluorescence derivatization Original Research Article

A highly selective and sensitive fluorometric method for the determination of bisphenols has been developed. This method is based on an intramolecular excimer-forming fluorescence derivatization with a pyrene reagent, 4-(1-pyrene)butyryl chloride (PBC), followed by reversed-phase liquid chromatography (LC). The bisphenols, containing two phenolic hydroxyl groups in a molecule, were converted to the corresponding dipyrene-labeled derivatives by reaction with PBC. The derivatives afforded intramolecular excimer fluorescence (440–520 nm) which can clearly be discriminated from normal fluorescence (360–420 nm) emitted from PBC and monopyrene-labeled derivatives of monophenols. The PBC derivatives of bisphenols could be separated by reversed-phase LC on an octyl column with isocratic elution. The detection limits (signal-to-noise ratio = 3) for bisphenols were 3.0–5.0 fmol, for a 20 μl injection. The method was successfully applied to the determination of bisphenol A in hot water in contact with commercially available baby bottle samples after solid-phase extraction.