Resolving the unresolved complex mixture in petroleum-contaminated sediments.
Comprehensive two-dimensional gas chromatography (GC x GC) was used to investigate the chemical composition of the unresolved complex mixture (UCM) of hydrocarbons in petroleum-contaminated marine sediments. The UCM hydrocarbons were extracted and separated with silica and silver-impregnated silica gel chromatography to yield four fractions (branched alkanes and cycloalkanes, monoaromatics, naphthalenes, and multi-ring PAHs) prior to GC x GC analysis. GC x GC separations used a poly-(dimethylsiloxane) stationary phase for volatility selectivity on the first dimension and a 14% cyanopropylphenyl polysiloxane phase for polarity selectivity on the second dimension to fully resolve monoaromatic, naphthalene, and multi-ring PAH compounds from the UCM. A chiral gamma-cyclodextrin phase was used for shape selectivity on the second GC x GC dimension to resolve individual branched alkanes and cycloalkanes in the saturates fraction of the UCM. The ability of GC x GC to resolve thousands of individual chemical components from the UCM will facilitate an understanding of the sources, weathering, and toxicity of UCM hydrocarbons.
Department of Science, United States Coast Guard Academy, New London, Connecticut 06320, USA. gfrysinger@cga.uscg.mil
Glenn S
GS
Frysinger
Richard B
RB
Gaines
Li
L
Xu
Christopher M
CM
Reddy
D002849:Chromatography, Gas; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D006838:Hydrocarbons / Q000032:analysis / Q000737:chemistry*; D010578:Petroleum; D012680:Sensitivity and Specificity; D014874:Water Pollutants, Chemical / Q000032:analysis*
D006838:Hydrocarbons; D010578:Petroleum; D014874:Water Pollutants, Chemical