Hydrodex are cyclodextrin phases, manufactured by Macherey-Nagel, for the separation of enantiomers via GC. The base material are cyclic oligosaccharides (β- or γ-cyclodextrin), derivatized regioselectively with different functional groups. Due to the high melting points of the cyclodextrins, they are diluted with polysiloxanes for GC applications. Therefore many compounds can be analyzed without derivatization (however, for certain substances enantioselectivity can be favorably influenced by formation of derivatives).
For Hydrodex Phases it is not possible to make a general prediction, which phase could solve a given separation task. Even for compounds with small structural differences or within homologous series the enantiodifferentiation can be quite different. The descriptions below list some of the typical separations possible with individual phases.
Water as solvent is strictly forbidden for all cyclodextrin phases. It is recommended to dry the sample before using and to dissolve it in an appropriate nonpolar solvent in any case.
Hydrodex β-PM:
Hydrodex β-3P:
Hydrodex β-6TBDM:
Hydrodex β-6TBDE:
Hydrodex β-TBDAc:
Hydrodex γ-TBDAc:
Hydrodex γ-DiMOM:
Column name | Phase | Polarity | USP | Diameter | Film thickness | Tmax[1] |
Hydrodex β-PM | Heptakis-(2,6-di-O-methyl-3-O-pentyl)-β-cyclodextrin | N/A | N/A | 0.25 mm | N/A | 230-250 °C |
Hydrodex β-3P | Heptakis-(2,6-di-O-methyl-3-O-pentyl)-β-cyclodextrin | N/A | N/A | 0.25 mm | N/A | 230-250 °C |
Hydrodex β-6TBDM | Heptakis-(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl)-β-cyclodextrin | N/A | N/A | 0.10 mm | N/A | 230-250 °C |
Hydrodex β-6TBDE | Heptakis-(2,3-di-O-ethyl-6-O-tert-butyldimethylsilyl)-β-cyclodextrin | N/A | N/A | 0.25 mm | N/A | 230-250 °C |
Hydrodex β-TBDAc | Heptakis-(2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-β-cyclodextrin | N/A | N/A | 0.25 mm | N/A | 220-240 °C |
Hydrodex γ-TBDAc | Octakis-(2,3-di-O-acetyl-6-O-tert-butyldimethylsilyl)-γ-cyclodextrin | N/A | N/A | 0.25 mm | N/A | 220-240 °C |
Hydrodex γ-DiMOM | Octakis-(2,3-di-O-methoxymethyl-6-O-tert-butyldimethylsilyl)-γ-cyclodextrin | N/A | N/A | 0.25 mm | N/A | 220-240 °C |
[ 1 ] Depending on the film thickness and whether working at constant temperature or with a gradient