Determination of polycyclic aromatic hydrocarbons by liquid chromatography-electrospray ionization mass spectrometry using silver nitrate as a post-column reagent

Liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) using silver nitrate as a post-column reagent has been used for the determination of 10 polycyclic aromatic hydrocarbons (PAHs) in river water. In this method, after all the PAHs were separated by reversed-phase liquid chromatography, analytes formed complexes with silver cation by mixing with silver nitrate solution. The complexes then transfer the molecular ion, [M] (+), of the PAHs by charge transfer using in source collision-induced dissociation. The positive ion ESI mass spectra of all PAHs tested in this study showed [M](+) as the base peak and abundant [M+Ag](+), [2M+Ag](+) with very weak or no [2M+Ag](+). For the sample extraction, several solid-phase extraction parameters using the blue-chitin column were optimized. The limits of detection (S/N=3) of all PAHs for the spiked river water sample ranged from 0.001 to 0.03 ng/ml, and the detector responses were linear up to 1 ng/mI (correlation coefficients greater than or equal to0.0998). Repeatability and reproducibility were in the range from 4.3 to 6.8% and from 6.2 to 9.5%, respectively. (C) 2001 Elsevier Science B.V. All rights reserved.