[Preparation of stationary phases of four beta-cyclodextrin derivatives for gas chromatography by sol-gel technique].

Heptakis (2,3,6-tri-O-ethyl)-beta-cyclodextrin (CD) (perethylated-beta-CD), heptakis (2,3,6-tri-O-propyl)-beta-CD (perpropylated-beta-CD), heptakis (2,3,6-tri-O-octyl)-beta-CD (peroctylated-beta-CD), and (2,6-di-O-benzyl)-beta-CD were used as stationary phases to prepare columns for gas chromatography by sol-gel technique. The method of coating the columns is similar to the dynamic method and the time required was shortened. Chromatographic characteristics such as column efficiency (around 3000 plates/m), column stability and reproducibility (relative standard deviation below 8.5%) were studied. The columns exhibited good separation ability for disubstituted benzene isomers, especially for xylenes and cresols. In addition, the three peralkylated-beta-CD columns offer better selectivity than the (2,6-di-O-benzyl)-beta-CD column.