COSMOSIL 5CSP-HPR column was developed for enantiomeric separation based on ligand exchange chromatography (LEC). LEC for the separation of enantiomers was introduced by Davankov in 1973. This column directly separates the enatiomers (e.g. ?-amino acids, ?-hydroxycarboxylic acids) having two polar functional groups in a near position, using mobile phase containing Cu (II) ions.
MATERIAL CHARACTERISTICS
 
COSMOSIL 5CSP-HPR
Silica gel
high purity porous spherical silica gel
Average particle size
5µm
Average pore size
approx. 120Å
Specific surface area
approx. 300m²/g

Separation of DL-a-alanine

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The chromatogram above shows enantiomeric separation of DL-a-alanine.
DL-a-alanine, detected by UV 254 nm upon complex formation with Cu (II) ions.

1A
Column: COSMOSIL 5CSP-HPR 4.6mmI.D.×50mm
Mobile phase 0.5 mmol/l CuSO4
Flow rate 1.0 ml/min
Temperature 30 C
Detection UV 254 nm
Sample 0.84 mg/ml
Injection vol. 1.0 µl
1B

Separation of DL-a-selenomethionine 

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2A
Column: COSMOSIL 5CSP-HPR 4.6mmI.D.×50mm
Mobile phase 5.0 mmol/l CuSO4
Flow rate 1.0 ml/min
Temperature 30 C
Detection UV 254 nm
Sample 0.32 mg/ml
Injection vol. 2.0 µl
2B

The chromatogram above shows enantiomeric separation of
DL-a-selenomethionine which be used in structural analysis of proteins. Since DL-a-selenomethionine contains selenium (a heavy atom), it interacts with the stationary phase strongly, therefore the retention time becomes very long. In order to maintain suitable retention time, it is necessary to raise the CuSO4 concentration. In practice, on the 5CSP-HPR column the retention time can be controlled simply by changing the CuSO4 concentration. The addition of organic solvents like acetonitrile decreases the retention time as well.

Cosmosil 5CSP-HPR Column