Elimination of Perfluorooctanoic Acid Interference from Liquid Chromatography System by Impurity Delay / 分析化学

ABSTRACT

A high performance liquid chromatography tandem mass spectrometric ( HPLC-MS/MS ) method was developed for the determination of seven perfluorinated alkyl acidin ( C4-C10 ) and perfluorooctane sulfonate in water. After the particulate was removed by leaching, surrogate standard was added, then the sample was loading to a pre-conditioned WAX cartridge for purification, and then the eluent was concentrated and analyzed by HPLC-MS/MS. Due to the situation that the fluoride polymer was unavoidable to be used in the LC system, a delay column was employed and the perfluorooctanoic acid ( PFOA ) of interference was departed from the PFOA in sample. The method detection limit ( MDL) of PFOA was 0. 8 ng/L, and the lowest quantitative concentration (LQC) was 3. 2 ng/L. For other compounds, the MDL was ranged from 0. 2 to 1. 2 ng/L, and the LQC was 0. 8-4. 8 ng/L. This method also had good reproducibility, for six duplicated samples, the relative standard deviations ( RSD ) of all target compounds were less than 16%. And the recoveries of target compounds at six spiked matrix samples ranged from 87% to 129%, and the RSD were less than 15%. Because of the connection of delay column, the background was well controlled, and a relatively lower MDL were obtained.