Simultaneous Enantioselective Separation of Polychlorinated Biphenyls and Their Methyl Sulfone Metabolites by Heart-Cut MDGC: Determination of Enantiomeric Fractions in Fish Oils and Cow Liver Samples

The potential of three capillary columns based on b-cyclodextrin (i.e., Chirasil-Dex, BGB-172, and BGB-176SE) has been studied for the simultaneous enantiomeric separation of polychlorinated biphenyls (PCBs) andmethylsulfonylmetabolites of PCBs (MeSO2-PCBs) employing a heart-cut multidimensional gas chromatographic system (heart-cut MDGC). Among the columns studied, the BGB-176SE capillary column provided the best results, allowing the simultaneous enantioselective resolution of six MeSO2-PCBs and six chiral PCBs; the Chirasil-Dex column did not resolve any of the studied MeSO2-PCBs; and a poor resolution was obtained for three MeSO2-PCBs when the BGB-172 column was employed. The developed method was successfully applied to two fish oil and one cow liver samples commercially available, which showed different enantioselective pattern. PCBs 91 and 176 presented a clear enrichment of the second eluted atropisomer in codfish oil, whereas in fish oil sample, slight enrichment of the first eluted atropisomer of CB45 and the second eluted atropisomer of CB136 were observed.