Analysis of phenols in water by high-performance liquid chromatography using coumarin-6-sulfonyl chloride as a fluorogenic precolumn label

A simple, sensitive and rapid reversed-phase high-performance liquid chromatography (RP-HPLC) method is proposed for the analysis of some environmentally important phenols in water. The use of coumarin-6-sulphonyl chloride (C6SCl) as a fluorescence-labeling reagent has been investigated. The compound reacts with phenols within 20 min under mild conditions (ambient temperature, pH 9.0) to give sulphonates that can be separated by RP-HPLC employing fluorescence detection at λex = 360 and λem = 460 nm. The optimum conditions for fluorescence, derivatization and chromatographic separation have been established and detection limits in the range 0.1–0.9 μg l−1 were obtained for the studied compounds. The calibration curves were linear for the range 6–200 μg l−1 for phenol, 3–200 μg l−1 for 2-chlorophenol, 4-chlorophenol and 2,3,5-trichlorophenol and for the range of 3–100 μg l−1 for 2,3-dichlorophenol and 3,5-dichlorophenol. The practical applicability of the method to environmental samples was demonstrated by analyzing drinking and industrial water samples spiked with the phenolic compounds.