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Native and derivative cyclodextrins (CD) have been widely used as chiral selectors in gas chromatography. Native b-CD has very high melting temperature, close to its thermal stability, and very low solubility in common matrices. A few amount of this native selector has been dissolved in dimethylformamide, glycerol, ionic liquids and in mixtures of these solvents with water [1], and some of these solutions have been used to prepare packed columns [2,3]. In order to overcome these drawbacks, derivatives of lower melting points have been proposed as chiral materials, chemically pure, dissolved in a chromatographic suitable polymer, or a few of them, chemically linked to the inner capillary wall. Permethyl b-CD is one of the chiral derivatives most universally recognized but its still high melting temperature (150ºC) precludes its use in pure liquid state. Some non-polar or weakly polar polysiloxanes have been proposed as chromatographically useful solvents for this selector, however, their polarities limit the amount of permethyl-b-CD that can be dissolved [4]. Several important theoretical and practical studies with both chiral materials have been conducted, and from these results, it has been attributed very high enantiorecognition ability to native cyclodextrins. However, in our opinion, the performance of native b-CD with its permethyl derivative under the same chromatographic conditions has no been clearly and exhaustively compared. We studied more polar solvents, such as Carbowax 20M, ethylammonium nitrate (EAN) and polyethylenimine (PEI) to increase the solubility of these materials at relatively low temperatures. Thus, we have built up capillary columns with both, native and permethylated chiral selectors in these three solvents by a dynamic method and using methanol as solvent. Promissory results have been achieved with permethyl-b-CD, but no enantiorecognition was observed with the native b-CD selector. Even more, retention factors of chemically different analytes were significantly smaller than those measured with a column coated with a film of the same thickness of pure Carbowax 20 M, at the same temperature. Attempts to understand these unexpected results are discussed. [1] W. Coleman et al., J. Phys. Org. Chem. 1993, 6, 651 [2] D. Sylbilska et al., J. Chromatog. 1991, 547, 283 [3] L.A. Kartsova et al., J. Anal. Chem. 2007, 62, 245 [4] A. Venema and P.J.A. Tolsma, HRC 1989, 12, 32