Abstract
Herein we describe an automated enantioselective isolation system that uses a gas chromatograph‐flame ionization detector (FID)‐preparative fraction collector to separate the enantiomers of chiral compounds. In this system, a switching device was coupled with six glass tubes containing an organic solvent for the separate collection of six compounds, thus eliminating the need for a manual collection procedure after separation by gas chromatography. To evaluate the usefulness of this system, we applied it to the separation and collection of the enantiomers of α‐hexachlorocyclohexane (α‐HCH), and we measured the estrogenic potency of each enantiomer by means of an MVLN cell (Michigan Cancer Foundation‐7 (MCF‐7) cell stably transfected with a pVit‐tk‐LUC reporter plasmid) bioassay and an estrogen receptor binding assay. The variability in the retention time of each enantiomer (relative standard deviation, n = 16) was typically < 0.05%. The recoveries of the dextrorotatory (+) and levorotatory (–) enantiomers of α‐HCH were about 68.8% and 73.4%, respectively. The overall quantity of each enantiomer of α‐HCH collected was about 300 μg. Both enantiomers of α‐HCH showed similar estrogenic activity. On the basis of the results obtained for α‐HCH, we concluded that this analytical method is suitable for the determination of the estrogenic activity of other chiral compounds. Such determinations are essential because enantiomers differ considerably in how they accumulate in organisms and decompose in the environment.