Comparison of multiple calibration approaches for the determination of volatile organic compounds in air samples by solid phase microextraction Arrow and in-tube extraction

Jose Ruiz-Jimenez; Hangzhen Lan; Yevgeny Leleev; Kari Hartonen; Marja-Liisa Riekkola

doi:10.1016/j.chroma.2019.460825

Comparison of multiple calibration approaches for the determination of volatile organic compounds in air samples by solid phase microextraction Arrow and in-tube extraction

J Chromatogr A. 2020 Apr 12:1616:460825. doi: 10.1016/j.chroma.2019.460825. Epub 2019 Dec 23.

Authors

Jose Ruiz-Jimenez¹, Hangzhen Lan¹, Yevgeny Leleev¹, Kari Hartonen¹, Marja-Liisa Riekkola²

Affiliations

¹ Department of Chemistry and Institute for Atmospheric and Earth System Research, P.O. Box 55, FI-00014 University of Helsinki, Finland.
² Department of Chemistry and Institute for Atmospheric and Earth System Research, P.O. Box 55, FI-00014 University of Helsinki, Finland. Electronic address: marja-liisa.riekkola@helsinki.fi.

PMID: 31924328
DOI: 10.1016/j.chroma.2019.460825

Abstract

Several calibration approaches were evaluated for the quantitation of volatile organic compounds in air using miniaturized exhaustive and non-exhaustive sampling techniques, such as in-tube extraction (ITEX) and solid phase microextraction (SPME) Arrow. Eleven compounds, 2-ethyl-hexanol, hexanal, nonanal, toluene, ethyl-benzene, methyl isobutyl ketone, acetophenone, p-cymene, α-pinene, trimethylamine and triethylamine, all them found in the natural air samples, were selected as model analytes. Liquid injection, liquid standard addition to the sorbent bed and gas phase standards provided by an automatic permeation system, were evaluated in the case of ITEX packed with laboratory-made 10% polyacrylonitrile (PAN) material. Two different approaches, based on sampling of gas phase compounds from the permeation system and from sample vial containing gas phase standards, were evaluated for SPME Arrow with two different coatings, commercial divinylbenzene-poly(dimethylsiloxane) (DVB-PDMS) and laboratory-made mesoporous Mobil Composition of Matter No. 41 (MCM-41). In addition, interface model approach was used for the calculation of the real concentration of the target analytes in the sample from the total amount of analytes injected into the GC-MS in the case of SPME Arrow. Similar results were obtained with the different approaches used for the quantitation by ITEX and SPME Arrow. However, the use of gas phase standards with sample matrix similar to the natural samples, allowed the permeation system to provide the most reliable results for the quantitation of the target analytes. For this approach, linearity (expressed as r² values) ranged between 0.991 and 0.999. The limit of detection ranged from 0.5 µg/m³ (trimethylamine, MCM-41) to 2.2 × 10^-4 µg/m³ (methyl isobutyl ketone, MCM-41). In addition, the use of the fully automated permeation system provided good reproducibility values that were between 1.4% (acetophenone, MCM-41) and 7.8% (methyl isobutyl ketone, 10% PAN). The linear ranges were at least 3 order of magnitude for all the studied analytes with the exception of the calibration curve developed for trimethylamine with SPME Arrow (linear ranges between LOQ and 4.9 µg/m³ (DVB-PDMS) and LOQ and 9.8 µg/m³ (MCM-41)).

Keywords: Air samples; Calibration; ITEX; Interface model; Permeation system; SPME Arrow.

Publication types

Comparative Study

MeSH terms

Air / analysis*
Calibration
Kinetics
Reproducibility of Results
Solid Phase Microextraction / methods*
Volatile Organic Compounds / analysis*

Substances

Volatile Organic Compounds