High performance solid-phase analytical derivatization of phenols for gas chromatography–mass spectrometry

The solid-phase analytical derivatization of phenols with pentafluoropyridine is performed. Fourteen phenols including chlorophenols and alkylphenols, could be efficiently adsorbed on a strong anion-exchange solid phase, Oasis MAX. The phenols adsorbed on Oasis MAX as phenolate ions were desorbed after derivatization with pentafluoropyridine. After optimization of the adsorption and derivatization, we established a procedure for the determination of the phenols in water samples by means of GC–MS. Under the optimized conditions, calibration curves were linear in the range of 10–1000 ng/l for the alkylphenols (100–10000 ng/l for nonylphenol) and 50–1000 ng/l for the others. By processing 100 ml samples, the method detection limits (MDLs) were in the range of 0.45–2.3 ng/l for the alkylphenols (8.5 ng/l for nonylphenol) and 2.4–16 ng/l for the others. Compared with the biphasic reaction system, the signal-to-noise ratios obtained by the solid-phase analytical derivatization were significantly higher. This is ascribed to the fact that coexisting neutral and acidic compounds are efficiently removed from the sample solution by this solid-phase analytical derivatization system.