| Autor: |
Martin PR; Department of Geosciences, Eberhard Karls University Tübingen, Schnarrenbergstr. 94-96, D-72076 Tübingen, Germany. philipp.martin@uni-tuebingen.de., Buchner D; Department of Geosciences, Eberhard Karls University Tübingen, Schnarrenbergstr. 94-96, D-72076 Tübingen, Germany. philipp.martin@uni-tuebingen.de., Jochmann MA; Instrumental Analytical Chemistry, University of Duisburg-Essen, D-45141 Essen, Germany., Haderlein SB; Department of Geosciences, Eberhard Karls University Tübingen, Schnarrenbergstr. 94-96, D-72076 Tübingen, Germany. philipp.martin@uni-tuebingen.de. |
| Jazyk: |
angličtina |
| Zdroj: |
Analytical methods : advancing methods and applications [Anal Methods] 2024 Feb 08; Vol. 16 (6), pp. 919-929. Date of Electronic Publication: 2024 Feb 08. |
| DOI: |
10.1039/d3ay01981k |
| Abstrakt: |
Compound-specific isotope analysis (CSIA) via gas chromatography-isotope ratio mass spectrometry (GC-IRMS) is a potent tool to elucidate the fate of (semi-)volatile organic contaminants in technical and environmental systems. Yet, due to the comparatively low sensitivity of IRMS, an enrichment step prior to analysis often is inevitable. A promising approach for fast as well as economic analyte extraction and preconcentration prior to CSIA is dispersive liquid-liquid microextraction (DLLME) - a well-established technique in concentration analysis of contaminants from aqueous samples. Here, we present and evaluate the first DLLME method for GC-IRMS exemplified by the analysis of chlorinated phenols (4-chlorophenol, 2,4-dichlorophenol, and 2,4,6-trichlorophenol) as model compounds. The analytes were simultaneously acetylated with acetic anhydride and extracted from the aqueous phase using a binary solvent mixture of acetone and tetrachloroethylene. With this method, reproducible δ 13 C values were achieved with errors ≤ 0.6‰ ( n = 3) for aqueous concentrations down to 100 μg L -1 . With preconcentration factors between 130 and 220, the method outperformed conventional liquid-liquid extraction in terms of sample preparation time and resource consumption with comparable reproducibility. Furthermore, we have demonstrated the suitability of the method (i) for the extraction of the analytes from a spiked river water sample and (ii) to quantify kinetic carbon isotope effect for 2,4,6-trichlorophenol during reduction with zero-valent zinc in a laboratory batch experiment. The presented work shows for the first time the potential of DLLME for analyte enrichment prior to CSIA and paves the way for further developments, such as the extraction of other compounds or scaling up to larger sample volumes. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
|
