Title: | Critical role of a pre-purge setup in the thermal desorption analysis of volatile organic compounds by gas chromatography with mass spectrometry |
Address: | "Department of Civil and Environmental Engineering, Hanyang University, Seoul, Republic of Korea" |
ISSN/ISBN: | 1615-9314 (Electronic) 1615-9306 (Linking) |
Abstract: | "In general, volatile organic compounds in ambient air are quantified by following a well-defined standard calibration procedure using a gas-/liquid-phase standard. If the liquid standard is analyzed by a thermal desorption, the solvent effect is unavoidable through the alteration of breakthrough properties or retention times. To learn more about the variables of the thermal desorption-based analysis, the effect of pre-purge conditions was evaluated for 18 volatile organic compounds with different types of sorbent tube materials by fixing standard volume (1 muL) and flow rate (100 mL/min). The gas phase calibration was also carried out as reference for the non-solvent effect. A single tube filled with Tenax TA exhibited the least solvent effect with the short pre-purge (1 min), while being subject to the breakthrough at or above 10 min pre-purge. For a three-bed sorbent tube with Carboxen 1000, at least 10 min of pre-purge was needed for the compounds with a retention time close to methanol (e.g., propanal). Another three-bed tube with Carbopack X reduced the solvent effect efficiently for a short pre-purge (2 min) without the breakthrough. As such, the solvent effect can be adjusted by the proper control of the sorbent tube application" |
Keywords: | Gas chromatography Methanol Pre-purge Solvent effects Sorbent tubes; |
Notes: | "PubMed-not-MEDLINEKim, Yong-Hyun Kim, Ki-Hyun eng Germany 2015/05/12 J Sep Sci. 2015 Jul; 38(14):2455-62. doi: 10.1002/jssc.201500367. Epub 2015 Jun 13" |