HIGH-RESOLUTION GAS-CHROMATOGRAPHIC TEST FOR THE CHARACTERIZATION OF ENANTIOSELECTIVE SEPARATION OF ORGANOCHLORINE COMPOUNDS - APPLICATION TO TERT.-BUTYLDIMETHYLSILYL BETA-CYCLODEXTRIN

Capillaries based on tert.-butyldimethylsilylated beta-cyclodextrin (T BDMS-CD) diluted in OV-1701 have gained increasing interest for the en antioselective separation of lipophilic polychlorinated pesticides. A modified test according to Schurig for chiral stationary phases was no t suitable for testing TBDMS-CD due the lack of sufficiently lipophili c compounds. A test mixture was developed containing the chiral polych lorinated pesticides alpha-hexachlorocyclohexane, cis- and trans-chlor dane, heptachlor-exo-epoxide and 3-endo,5-exo,6-endo,8,8,9,10,10-nonac hloro-brnane. They are especially sensitive to changes in the enantios elective properties of TBDMS-CD which is also frequently used for thes e compounds. Cis- and trans-chlordane with different enantiomer ratios facilitate the detection of changes of the enantiomer elution order. Test results of laboratory-made and commercial capillaries are present ed showing the usefulness of the test to detect differences in the ena ntioselective behaviour such as changes in the elution order of enanti omers. Electrospray MS was used for the characterisation of TBDMS-CD. The analysed batches contained homologues with 7-10 TBDMS groups in a mixture of variable composition. This is assumed to be the reason for the observed differences. (C) 1997 Elsevier Science B.V.