Simultaneous analysis of 14 short- and long-chain perfluorinated compounds in water by liquid chromatography-tandem mass spectrometry using solid phase extraction

Abstract

A solid phase extraction (SPE)-ultrahigh pressure liquid chromatography (UPLC) method coupled with tandem mass spectrometry was developed for the simultaneous analysis of the 14 short- and long-chain perfluorinated compounds (PFCs) in water. Water sample was concentrated and purified through WAX mixed-mode SPE cartridges. The separation of PFCs was performed on a BEH C18 column with gradient elution using methanol-5 mmol/L ammonium acetate as mobile phases. The PFCs were quantified by internal standard method in multiple-reaction monitoring mode. The calibration curves of the 14 PFCs were linear in the range of 0.1-50 μg/L with the correlation coefficients > 0.99. The limits of detection (S/N = 3) and quantitation (S/N = 10) of the method were 0.09-1.15 ng/L and 0.29-3.85 ng/L, respectively. The average recoveries of eight PFCs at three spiked levels of 2, 10 and 20 ng/L were 85.0%, 120.2% and 117.4%, with the relative standard deviations of 9.2%, 9.0% and 6.6%, respectively. The recoveries of the rest six PFCs were low due to unavoidable strong adsorption on the bottle/tube walls during sample pretreatment. The method was applied in the determination of PFCs in real samples of a lake in South China. Four short-chain and five long-chain PFCs were detected with mass concentrations of 41.29-49.05 ng/L and 98.43-111.02 ng/L, respectively. The results show that the method is suitable for the simultaneous analysis of short- and long-chain perfluorinated compounds in environmental water.