QUANTIFICATION OF PARENT AND ALKYL POLYCYCLIC AROMATIC HYDROCARBONS IN CRUDE OIL SAMPLES USING COMPREHENSIVE TWO-DIMENSIONAL GAS CHROMATOGRAPHY

 

Jacolin A. Murray, Michele M. Schantz and John Kucklick

 

 

Following the release of crude oil from the Deepwater Horizon site in the Gulf of Mexico, there was renewed interest in quantifying the analytes associated with crude oil.

Both parent and alkyl polycyclic aromatic hydrocarbons (PAHs) are of interest due to their toxicity to marine organisms. Other classes of analytes of interest include hopanes and steranes. Due to the complexity of crude oil, quantification of the analytes by gas chromatography-mass spectrometry (GC-MS) first requires sample cleanup and fractionation, and often requires multiple analyses on different stationary phase to quantify the analytes of interest. Comprehensive two-dimensional gas chromatography (GCxGC) has the capability of separating thousands of analytes in complex matrices due to the substantial enhancement of peak capacity over traditional GC. This technique can be used to reduce the number of sample preparation steps prior to analysis. In this presentation, the quantitative capability of GCxGC time-of-flight MS will be investigated for the analysis of many classes of compounds in crude oil and coal tar extract Standard Reference Materials focusing on parent and alkyl PAHs as well of selected hopanes and steranes with little or no sample preparation. The separation was optimized by comparing the separation on several different column sets at several different chromatographic conditions. The quantitative results were compared to other methods of analysis such GC-MS with sample cleanup. The analysis of these targeted analytes in other complex matrices such as sediment and marine tissues will also be explored.