Trace analysis of polyaromatic hydrocarbons in water using multiphoton ionization-membrane introduction mass spectrometry

Abstract

We have combined the resonance‐enhanced multiphoton ionization (REMPI) technique with membrane introduction mass spectrometry to significantly enhance its performance in the direct analysis of select polyaromatic hydrocarbons (PAHs) in water. We have used UV radiation from a pulsed KrF (λ = 248nm) excimer laser to selectively ionize PAHs sampled directly from their aqueous solutions by a silicone membrane probe. The ionization and mass analysis is carried out using a modified GCQ ion trap mass spectrometer. The REMPI method provides exceptional selectivity as demonstrated in the detection of parts‐per‐trillion levels of pyrene in the presence of abundant background neutrals from the matrix, pump‐oil, membrane and other sources. The instrumentation and experimental results using naphthalene and pyrene are presented. The selectivity and sensitivity of standard electron impact ionization is also compared with 248 nm multiphoton ionization to illustrate the improvements in performance. © 1998 John Wiley & Sons, Ltd. This paper was produced under the auspices of the US Government and it is therefore not subject to copyright in the US.

Process Analytical Chemistry—Application of Mass Spectrometry in Environmental Analysis: An Overview

“…Several sources have been investigated jointly with membrane introduction. Examples include membrane combination with MPI for polyaromatic hydrocarbon analysis in water (73) and the connection of MIMS with ionization by interchange of charge (74).…”

Rapid analysis of aromatic contaminants in water samples by means of laser ionization mass spectrometry

“…Although their mass range is limited compared with time-of-flight instruments it still covers a large percentage of mass spectrometric tasks. Within the last decade compact, robust, and relatively inexpensive quadrupole ion-traps have been developed and recently this type of mass spectrometer was coupled to laser ionization outside [12] and inside the trap [13].…”

Fast and direct screening of solid materials for their potential liberation of hydrophobic organic compounds using hot cell membrane inlet mass spectrometry

“…To analyze semi‐VOCs (boiling point (bp) above 250°C) using MIMS, various forms of stimulated desorption are needed and the analysis is normally performed using the trap‐and‐release technique12, 13 (T&R‐MIMS). In the T&R‐MIMS technique the analyte is preconcentrated in the membrane, before it is rapidly released either directly into the ion source of the mass spectrometer14–20 or into a hot transfer line leading to the ion source 21–24…”