title: Evaluation of the solid-phase extraction (SPE) cartridge method in combination with thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) for the analysis of different VOCs in liquid matrices in varying pH conditions.
abstract: In this study, the solid-phase extraction (SPE) method combined with thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) method is evaluated for the analysis of liquid-phase volatile organic compounds (LVOCs). Calibration experiments were performed on a number of polar and nonpolar LVOCs (including aromatic compounds, ester, ketones, and alcohol) as a function of solution pH. If the relative sensitivity of the SPE-TD-GC-MS method is compared between different VOCs across a wide range of pH (1, 4, 7, 10, and 13), optimum sensitivities for most VOCs are derived at the neutral pH. However, there were some exceptions to the general trend with the maximum sensitivity occurring either at a moderately basic pH (methyl isobutyl ketone and butyl acetate) or extremely acidic conditions (isobutyl alcohol). It was also noticed that the relative ordering of sensitivity was changed, as the pH conditions of the solution vary. The use of internal standard (IS: chlorobenzene) resulted in a notable improvement in both relative sensitivity and reproducibility for most compounds.
authors.affiliation: Department of Environment and Energy, Sejong University, Seoul, Korea.
authors.forename: Sudhir Kumar
authors.initials: SK
authors.lastname: Pandey
authors.forename: Ki-Hyun
authors.initials: KH
authors.lastname: Kim
mesh_terms: D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D052616:Solid Phase Extraction / Q000295:instrumentation / Q000379:methods*; D055549:Volatile Organic Compounds / Q000032:analysis* / Q000302:isolation & purification; D014867:Water / Q000737:chemistry*
chemical_list: D055549:Volatile Organic Compounds; D014867:Water