Comparison of three diacetyl-cycloclextrin gas chromatographic stationary phases: Possible indicators of the chemical nature of constituents of volatile oils

Relative retention times (RR) versus n-undecane for thirty solutes from volatile oils are determined for Alpha-, Beta- and Gamma-Dex 225 capillaries. These are diacetyl-cyclodextrin phases to which some solutes respond as though they were conventional phases. However, lowest RR of the three on Beta-Dex 225 indicates a bicyclic terpenoid, Highest RR on this phase can be by an aromatic, or an acyclic terpenoid. Lowest values of correlation coefficients between pairs of variously modified-cyclodextrins for RR of ten selected diverse solutes occur with combinations of any one-Dex 225 phase, indicating that these are desirably different to many other modified-CDs, although not to each other.