Method for analysis of polar volatile trace components in aqueous samples by gas chromatography
2005 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 77, no 10, 3365-3371 p.Article in journal (Refereed) Published
A new method has been developed for direct analysis of volatile polar trace compounds in aqueous samples by gas chromatography. Water samples are injected onto a short packed precolumn containing anhydrous lithium chloride. A capillary column is coupled in series with the prefractionation column for final separation of the analytes. The enrichment principle of the salt precolumn is reverse to the principles employed in conventional methods such as SPE or SPME in which a sorbent or adsorbent is utilized to trap or concentrate the analytes. Such methods are not efficient for highly polar compounds. In the LiCl pre-column concept, the water matrix is strongly retained on the hygroscopic salt, whereas polar as well as nonpolar volatile organic compounds show very low retention and are eluted ahead of the water. After transfer of the analytes to the capillary column, the retained bulk water is removed by backflushing the precolumn at elevated temperature. For direct injections of 120 μL of aqueous samples, the combined time for injection and preseparation is only 3.5 min. With this procedure, direct repetitive automated analyses of highly volatile polar compounds such as methanol or tetrahydrofuran can be performed, and a limit of quantification in the low parts-per-billion region utilizing a flame ionization detector is demonstrated.
Place, publisher, year, edition, pages
2005. Vol. 77, no 10, 3365-3371 p.
Capillarity, Distillation columns, Gas chromatography, Ionization
IdentifiersURN: urn:nbn:se:kth:diva-4913DOI: 10.1021/ac040170kISI: 000229206800042ScopusID: 2-s2.0-18844442547OAI: oai:DiVA.org:kth-4913DiVA: diva2:6849
QC 20100922. Uppdaterad från Submitted till Published (20100922). Tidigare Titel "A new method for analysis of polar volatile trace components in aqueous samples by gas chromatography".