title: Determination of polycyclic aromatic hydrocarbons and their oxy-, nitro-, and hydroxy-oxidation products.
abstract: A sensitive method has been developed for the trace analysis of PAHs and their oxidation products (i.e., nitro-, oxy-, and hydroxy-PAHs) in air particulate matter (PM). Following PM extraction, PAHs, nitro-, oxy-, and hydroxy-PAHs were fractionated using solid phase extraction (SPE) based on their polarities. Gas chromatography-mass spectrometry (GC-MS) conditions were optimized, addressing injection (i.e., splitless time), negative-ion chemical ionization (NICI) parameters, i.e., source temperature and methane flow rate, and MS scanning conditions. Each class of PAH oxidation products was then analyzed using the sample preparation and appropriate ionization conditions (e.g., nitro-PAHs exhibited the greatest sensitivity when analyzed with NICI-MS while hydroxy-PAHs required chemical derivatization prior to GC-MS analysis). The analyses were performed in selected-ion-total-ion (SITI) mode, combining the increased sensitivity of selected-ion monitoring (SIM) with the identification advantages of total-ion current (TIC). The instrumental LODs determined were 6-34 pg for PAHs, 5-36 pg for oxy-PAHs, and 1-21 pg for derivatized hydroxy-PAHs using electron ionization (GC-EI-MS). NICI-MS was found to be a useful tool for confirming the tentative identification of oxy-PAHs. For nitro-PAHs, LODs were 1-10 pg using negative-ion chemical ionization (GC-NICI-MS). The developed method was successfully applied to two types of real-world PM samples, diesel exhaust standard reference material (SRM 2975) and wood smoke PM.
authors: University of North Dakota, Department of Chemistry, Grand Forks, ND 58202, USA.
authors: R E
authors: RE
authors: Cochran
authors: N
authors: N
authors: Dongari
authors: H
authors: H
authors: Jeong
authors: J
authors: J
authors: Beránek
authors: S
authors: S
authors: Haddadi
authors: J
authors: J
authors: Shipp
authors: A
authors: A
authors: Kubátová
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D010084:Oxidation-Reduction; D052638:Particulate Matter / Q000032:analysis*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D052616:Solid Phase Extraction
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D011084:Polycyclic Aromatic Hydrocarbons