Enantiomeric resolution of persistent compounds of technical toxaphene (CTTs) on t-butyldimethylsilylated β-cyclodextrin phases

Rapid enantiomeric separation of polychlorinated biphenyls by electrokinetic chromatography using mixtures of neutral and charged cyclodextrin derivatives

“…1b). These chiral separations were also reported by GC [8,9] but in general very long analysis times were required (more than 1 h). On the other hand, these results do not agree with those obtained by CD-MEKC [13,14], in which g-CD was more effective in the enantiomeric separation of chiral PCBs than b-CD due to the larger size of the cavity of g-CD compared to b-CD.…”

“…relevance because each enantiomer may have differGas chromatography (GC), usually employed to ent toxicity, activity or metabolic pathways. Moreseparate PCB congeners, has also been employed to perform the separation of chiral PCBs [5][6][7][8][9][10][11]. Nevertheless, the characteristics of capillary electro- and flexibility) make this technique competitive with GC in the field of the enantiomeric separations [12].…”

Synthesis, NMR Spectroscopic Characterization and Polysiloxane‐Based Immobilization of the Three Regioisomeric Monooctenylpermethyl‐β‐cyclodextrins and Their Application in Enantioselective GC

“…[34] Reversal of the elution order of enantiomers has even been observed for apparently identical modified cyclodextrin chiral stationary phases. [35] Therefore, in the present work, we have exercised great care to synthesize, coat, and immobilize the three positional O-2-, O-3-, and O-6-Chirasil-Dex regioisomers onto fused silica capillaries under identical conditions. We demonstrate that the differences in enantioselective chromatographic behaviour are neither pronounced nor negligible.…”

Enantioseparation of the compounds of technical toxaphene (CTTs) on 35% heptakis (6-O-tert-butyldimethylsilyl-2,3-di-O-Methyl)-β-cyclodextrin in OV1701

“…Because of the different behavior of enantiomers in a chiral environment, enantioselective analysis currently plays an important role in environmental chemistry [4J. First reports of the separation of CTT enantiomers were published in 1994 [5,6]; so far resolution of the enantiomers of CTTs has been achieved on tert-butyldimethylsilylated 13-cyclodextrin (13-BSCD) only [4,7]. Chiral stationary phases (CSPs) based on ~-BSCD were introduced by Blum and Aichholz [8].…”

“…Chiral stationary phases (CSPs) based on ~-BSCD were introduced by Blum and Aichholz [8]. On this CSP enantioseparation of seven persistent CTTs was achieved in one GC run [7]. The enantiomers of some CTTs could not, however, be separated on 13-BSCD and the lack of a confirmatory CSP for the enantioselective analysis of CTTs in environmental samples was regrettable.…”