Identification of polycyclic aromatic compounds in urban air particulate extracts by on-line coupled LC–GC–ITD–MS
Abstract
A method has been developed to identify and quantify parent, oxygenated, nitrated and alkylated polycyclic aromatic compounds (PAC) adsorbed onto urban air particulates by using supercritical fluid extraction and online multidimensional chromatographic methods coupled to mass spectrometry. High pressure, normal phase, liquid chromatography has been coupled to a high resolution gas chromatograph and an ion trap detector mass spectrometer. The instrument was configured to use an on-column LC–GC interface, enabling partially concurrent solvent evaporation with an early solvent vapour exit. This instrument was used to identify substituted polycyclic aromatic compounds contained in the extracts obtained from the supercritical fluid extraction of urban air particulates collected at the roadside in Leeds by a high volume sampler. Compounds identified included alkylated pyrene and chrysene species, nitrated fluoranthene and pyrene species and many oxygen containing PAC.