Stationary phases
From Chiral-separations.com
The chiral stationary phases used for chiral gc columns vary in selectivity and polarity and each phase is particularly suitable for only some applications. The table in the next section gives some very rough estimations about target compounds that are generally well resolved into their enantiomers by a specific chiral phase (or enantioselective gc column, respectively). However, it is not possible to accurately predict the resolution behaviour of a certain compound/stationary phase pair.
Each day new chiral separation challenges arise and in many cases method development by trial-and-error is necessary. We can recommend specific chiral gc columns that most likely achieve your enantiomeric resolutions, but we can not guarantee so for compounds we have not studied in our own laboratory.
Please contact us to discuss your chiral separation problem and state the volatility and functional groups of your target molecule as detailled as possible. We will recommend potentially suitable chiral gc columns based on our large application database free of charge. Alternatively, you might be interested in our custom method development service for chiral separations.
You may contact us at support@chiral-separations.com for free advice and quotations.
Chemical identity of the enantioselective stationary phases
All our enantioselective stationary phases are based on modified cyclodextrins. Depending on the pattern of substitution, different selectivities and polarities arise.
| product name | stationary phase | analytes |
|---|---|---|
| Cyclodextrin E | 2,6-Pentyl-3-Butyryl-gamma-Cyclodextrin | oxygenated terpenes, alcohols, epoxides |
| Cyclodextrin G | 6-Methyl-2,3-Pentyl-gamma-Cyclodextrin | monoterpene hydrocarbons, volatile/low temperature |
| Cyclodextrin H | 2,6-Methyl-3-Pentyl-gamma-Cyclodextrin | terpenes, alcohols, alkenes |
| Cyclodextrin 3P | 2,6-Methyl-3-Pentyl-beta-Cyclodextrin | terpenes, alcohols, alkenes |
| Cyclodextrin TM | 6-TBDMS-2,3-Methyl-beta-Cyclodextrin | PCB, polycyclic or chlorinated aromatics, pesticides |
| Cyclodextrin TE | 6-TBDMS-2,3-Ethyl-beta-Cyclodextrin | pharmacopeia separations of essential oils |
| Cyclodextrin TA | 6-TBDMS-2,3-Acetyl-beta-Cyclodextrin | oxygenated terpenes, aromatics, low volatile |
| Cyclodextrin PM | 2,3,6-Methyl-beta-Cyclodextrin | legacy phase for many analytes |
Comparison chart of chiral GC columns
The following table gives an overview which stationary phases are equivalent or compatible. Since each manufacturer might use special derivatisation techniques, only estimations of equivalency can be given.
| Chiral-Separations.com | Macherey-Nagel | Supelco | Agilent | Varian | Restek |
|---|---|---|---|---|---|
| Cyclodextrin E | Lipodex E | ||||
| Cyclodextrin G | Lipodex G | ||||
| Cyclodextrin H | |||||
| Cyclodextrin TM | Hydrodex β-TBDM | β-DEX-325 | CycloSil-B | Rt-βDEXsm | |
| Cyclodextrin TE | Rt-βDEXse | ||||
| Cyclodextrin TA | Hydrodex β-TBDAc | β-DEX-225 | Rt-βDEXsa | ||
| Cyclodextrin PM | Hydrodex PM | HP-Chiral β | CP-Cyclodextrin-β-2,3,6-M-19 | Rt-βDEXm |
Hydrodex and Lipodex are registered trademarks of Macherey-Nagel. Rt-βDEX are registered trademarks of Restek Inc.
Specifications
General specifications
Highly desactivated fused silica capillary, inner diameter 250 μm. All columns pre-conditioned, individually tested and documented including chromatogram and data sheet, serial numbered on column carrier. Each column is delivered on an innovative high-quality, rigid and robust, light-weight aluminium carrier. We can deliver any column length; default lenghts are 10 m, 25 m and 30 m.
TwinGuard technology
All stationary phases are also available as TwinGuard columns with integrated pre- and post-column; pre-column (injector side) and post-column (detector side) are clearly marked with red and white labels directly on the capillary, respectively. Layout: 5 m deactivated pre-column, 25 m chiral stationary phase, 1 m deactivated post-column. Read more about TwinGuard!
Special requirements
Please inquire for other stationary phases, column diameters or any other special requirements. We will be pleased to discuss your ideas and offer free quotations! We produce tailor-made chiral gc columns if necessary to solve your chiral separation challenge.