Simultaneous determination of bisphenol A and alkylphenols by LC atmospheric pressure-ionization MS

An analytical method for the determination of bisphenol A and alkylphenols with liquid chromatography/mass spectrometry (LC/MS) has been developed. Un der reversed-phase liquid-chromatographic conditions, bisphenol A and seven alkylphenols have been analyzed using atmospheric-pressure chemical ioniza tion(APCI) and electrospray ionization (ESI) methods. The effects of post-c olumn modification of the liquid chromatographic mobile phase, the fragment or voltage with ESI methods and the temperature of the vaporizer with APCI methods on the sensitivity for the detection of bisphenol A and alkylphenol s were examined. The sensitivities of the APCI methods were higher than the se of the ESI methods. Large volumes of river water samples were directly i njected into the precolumn, and then bisphenol A and alkylphenols were sepa rated by an analytical column with a column-switching technique. The limit of detection (LOD) of these phenols ranged from 5 ppt to 20 ppt. The overal l recoveries of phenols were from 93.0 to 112.4% {RSD (n = 5) from 2.1 to 5 .3% } for river water.