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SummaryThis paper describes an evaluation of the chromatographic performance of columns coated with amorphous cyclodextrin (CD) derivatives, in particular 2,3,6-tripentyl-P-CD (2,3,6-TriPe-P-CD), 2,6-dipentyl-3-methyl-P-CD (2,6-DiPe-3-Me-P-CD), and 2,6-dimethyl-3-pentyl-fl-CD (2,6-DiMe-3-Pe-P-CD), all diluted in polysiloxane (OV-1701 or OV-1701 -OH), for the separation of the enantiomers of volatile compounds. 2,6-DiMe-3-Pe-P-CD in OV-1701 offers Performance comparable with (or better than) that of the other two CDs, and without their drawbacks (inconsistency of results, as described previously).This article compares the separating ability of 2,6-DiMe-3-Pe-P-CD and 2,3,6-TriMe-P-CD, and describes the influence of the CD derivative to polysiloxane ratio, the minimum operating temperatures of the columns, and the reproducibility and consistency of performance of columns coated with the former CD derivative diluted in polysiloxane.

This article reviews papers published over the period 1989-94 concerning applications of cyclodextrin derivatives (CDDs) to the separation of volatile racemates in the essential oil, extract, flavour and aroma fields by CGC techniques. For each application, the racemate separated, the CDD used for the separation and the matrix analysed are reported. The applications are grouped by the analytical technique employed: capillary gas chromatography and capillary gas chromatography-mass spectrometry (CGC and CGC-MS); multidimensional gas chromatography (MDGC); capillary gas chromatography-isotope ratio-mass spectrometry (CGC-IRMS); liquid chromatography-capillary gas chromatography (HPLC-CGC).KEY WORDS cyclodextrin derivatives; capillary gas chromatography; (CGC); CGC-MS; MDGC;CGC-IRMS; HPLC-CGC; enantiomer separation; essential oils; extracts; flavour; aroma INTRODUCTIONThe introduction of derivatized cyclodextrins (CDD) as stationary phases to separate volatiles has been a milestone in GC enantiomer separation. The development of CDDs has greatly facilitated these separations, most of which are now carried out without derivatization. Since the number of racemates separated by CDDs is now very large, and since the stability and reproducibility of capillary GC columns prepared with CDDs is now very high, the use of CDDs is becoming increasingly widespread in routine analysis. Enantiomer separation is fundamental in the fields of flavours and essential oils, because it gives access to biogenetic information concerning a compound and very often, as a consequence, the corresponding matrix; it makes it possible to determine the enantiomeric excess of a component in a sample very quickly, and last, but not least, to identify possible adulterations in products of natural origin.A number of interesting reviews on different aspects of these fields have already been published. In particular, Mosand1122 reviewed the This article reviews papers concerning applications of CDD to the separation of volatile racemates in the essential oil and flavour fields by CGC techniques. We will therefore not deal with theory, separation mechanisms, chromatographic behaviour, development of new CDDs for CGC or packed column GC separation.The article is divided into sections, by the analytical technique employed: capillary gas chromatography and capillary gas chromatography-mass spectrometry (CGC and CGC-MS); multidimensional gas chromatography (MDGC); capillary gas chromatography-isotope ratio-mass spectrometry (CGC-IRMS), liquid chromatography-capillary gas chromatography (LC-CGC). Each section is in turn divided into two subsections, the first dedicated to essential oils and the second to extracts and flavour and aroma compounds: thus, the analysis of the same compound, either in the same or in different matrices, if carried out with different techniques, The period covered is 1989-94; articles reported in Chemical Abstracts and/or the bibliography section of the Journal of Chromatography and Analytical Abstracts are reviewed. Considering the...

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