A combined microextraction procedure for isolation of polycyclic aromatic hydrocarbons in ambient fine air particulate matter with determination by gas chromatography-tandem mass spectrometry.

A novel combined vortex-assisted dispersive liquid-liquid microextraction (VA-DLLME)-micro-solid-phase extraction (μ-SPE) procedure for polycyclic aromatic hydrocarbons (PAHs) in ambient fine particulate matter of aerodynamic diameter of  ≤ 2.5 µm (PM _2.5 ), was developed. PM _2.5 was collected on polytetrafluoroethylene (PTFE)-coated glass fiber filter, that was first processed by ultrasonicating in aqueous solution. Then, VA-DLLME, followed by µ-SPE, were applied to the solution using 1-octanol and graphene oxide as extractant and sorbent, respectively for extracting the PAHs. The PAHs were determined by gas chromatography-tandem mass spectrometry (GC-MS/MS). Parameters affecting the extraction efficiency including selection of the sorbent, duration of DLLME and µ-SPE, desorption solvent type, and ultrasonication-assisted desorption time were investigated. Under the optimum extraction conditions, the method exhibited linear ranges of 0.5-50 μg/L and 0.5-100 μg/L depending on the analytes. The limits of detection were in the range of 0.013 μg/L-0.135 μg/L. The developed method was applied to determine the PAHs in genuine PM _2.5 samples collected on PTFE glass fiber filters. The concentration levels in the atmospheric PM _2.5 were determined to be from below the limit of quantification to 0.135 ng/m ³ . The relative recoveries obtained from spiked concentrations at 1 μg/L and 5 μg/L were in the range 57-88% with relative standard deviations <14%.
Competing Interests: Declaration of Competing Interest The authors declare that this manuscript has not been submitted to any other journal.
(Copyright © 2019 Elsevier B.V. All rights reserved.)