A complete, sensitive and selective procedure was developed for gas chromatographic determination of perfluoroalkyl carboxylic acids (PFCAs, C5 - C12) in river water samples. A rapid and simple derivatization procedure was developed and optimized at first, using isobutyl chloroformate (IBCF) to convert the acids into the more volatile isobutyl esters. The second task was to find the most suitable stationary phase for separation of perfluoroalkyl carboxylic acids by GC. The retention characteristics of PFCA isobutyl esters were measured and compared on 9 different stationary phases. The physical-chemical parameters of analyte interactions with stationary phase were monitored on selected column Rtx-200MS, and these parameters were compared with a non-fluorinated homologue - octanoic acid. A sensitive GC-MS system was used with negative chemical ionization, which is suitable for the selected type of fluorinated analytes. The developed method exhibits very low limits of detection and determination of PFCA isobutyl esters: 0.05 - 9.7 ng mL-1 (LOD) and 0.16 - 32.2 ng mL-1 (LOQ). An optimum pre-concentration technique was found for real water samples, where SPE SupelTM-Select HLB cartridges were used. In these cartridges, PFCAs were captured as ion- pairs with enrichment factor of 400. The recoveries of...
| Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:311781 |
| Date | January 2012 |
| Creators | Dufková, Veronika |
| Contributors | Čabala, Radomír, Feltl, Ladislav, Kubinec, Róbert |
| Source Sets | Czech ETDs |
| Language | Czech |
| Detected Language | English |
| Type | info:eu-repo/semantics/doctoralThesis |
| Rights | info:eu-repo/semantics/restrictedAccess |
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