Chlorine isotope fractionation of a semi-volatile organochlorine compound during preparative megabore-column capillary gas chromatography

• Published in: Journal of Chromatography A 2006-01, Vol.1103 (1), p.133-138
• Main Authors: Holmstrand, Henry, Mandalakis, Manolis, Zencak, Zdenek, Gustafsson, Örjan, Andersson, Per
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Chemistry; Chlorine - chemistry; Chlorine isotope fractionation; Chromatographic methods and physical methods associated with chromatography; Chromatography, Gas - instrumentation; Chromatography, Gas - methods; Compound specific chlorine isotope analysis; DDT; DDT - chemistry; Exact sciences and technology; Gas chromatographic methods; Isotopes - analysis; Mass Spectrometry - methods; Preparative gas chromatography; Reproducibility of Results; Thermal ionization mass spectrometry; Volatilization
• ISSN: 0021-9673
• DOI: 10.1016/j.chroma.2005.11.009

Chlorine isotope fractionation during preparative capillary gas chromatography (pcGC) was investigated using 1,1,1-trichloro-2,2-bis( p-chlorophenyl)ethane (DDT) as a model compound for semi-volatile organochlorine (OCl) molecules. Chlorine isotope analysis by thermal ionization mass spectrometry revealed no significant alteration of the chlorine isotope composition when the whole peaks were collected in pcGC (δ 37Cl −3.2‰ versus −3.6‰ for the unprocessed DDT, ±0.5‰ SD). However, distinct isotope fractionations were measured for the front (δ 37Cl −5.1‰) and tail (δ 37Cl −1.8‰) segments of partially collected samples. Isolation of individual OCls by pcGC enables accurate off-line chlorine isotope analysis, and thus facilitates the investigation of naturally occurring OCls.