Chiral column chromatography
Encyclopedia
Chiral column chromatography is a variant of column chromatography
in which the stationary phase contains a single enantiomer
of a chiral
compound rather than being achiral. The two enantiomers of the same analyte compound differ in affinity
to the single-enantiomer stationary phase and therefore they exit the column at different times.
The chiral stationary phase can be prepared by attaching a suitable chiral compound to the surface of an achiral support such as silica gel
, which creates a Chiral Stationary Phase (CSP). Many common chiral stationary phases are based on oligosaccharides such as cellulose
or cyclodextrin
(in particular with β-cyclodextrin, a seven sugar ring molecule). As with all chromatographic methods, various stationary phases are particularly suited to specific types of analytes.
Chiral Stationary Phases are much more expensive than comparable achiral stationary phases such as C18.
The principle can be also applied to the fabrication of monolithic HPLC columns or gas chromatography columns.
Column chromatography
Column chromatography in chemistry is a method used to purify individual chemical compounds from mixtures of compounds. It is often used for preparative applications on scales from micrograms up to kilograms.The main advantage of column chromatography is the relatively low cost and disposability...
in which the stationary phase contains a single enantiomer
Enantiomer
In chemistry, an enantiomer is one of two stereoisomers that are mirror images of each other that are non-superposable , much as one's left and right hands are the same except for opposite orientation. It can be clearly understood if you try to place your hands one over the other without...
of a chiral
Chirality (chemistry)
A chiral molecule is a type of molecule that lacks an internal plane of symmetry and thus has a non-superimposable mirror image. The feature that is most often the cause of chirality in molecules is the presence of an asymmetric carbon atom....
compound rather than being achiral. The two enantiomers of the same analyte compound differ in affinity
Chemical affinity
In chemical physics and physical chemistry, chemical affinity is the electronic property by which dissimilar chemical species are capable of forming chemical compounds...
to the single-enantiomer stationary phase and therefore they exit the column at different times.
The chiral stationary phase can be prepared by attaching a suitable chiral compound to the surface of an achiral support such as silica gel
Silica gel
Silica gel is a granular, vitreous, porous form of silica made synthetically from sodium silicate. Despite its name, silica gel is a solid. It is a naturally occurring mineral that is purified and processed into either granular or beaded form...
, which creates a Chiral Stationary Phase (CSP). Many common chiral stationary phases are based on oligosaccharides such as cellulose
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....
or cyclodextrin
Cyclodextrin
Cyclodextrins are a family of compounds made up of sugar molecules bound together in a ring ....
(in particular with β-cyclodextrin, a seven sugar ring molecule). As with all chromatographic methods, various stationary phases are particularly suited to specific types of analytes.
Chiral Stationary Phases are much more expensive than comparable achiral stationary phases such as C18.
The principle can be also applied to the fabrication of monolithic HPLC columns or gas chromatography columns.