Daicel Crown Ether Columns
CROWNPAK® CR(+) & CR(-) contain a chiral crown ether as a chiral selector, which is coated onto a 5-µm silica support. CROWNPAK selectors are mainly used to separate chiral amino acids and other small molecules with primary amine groups. The elution order of the enantiomers can be reversed when necessary.
Acidic mobile phases such as perchloric acid (pH 1 to 2), are used to operate these columns under standard conditions. To shorten the retention time of hydrophobic samples, the addition of methanol (15% maximum v/v) has been shown to be effective for CROWNPAK CR(+) & CR(-).
CROWNPAK CR-I(+) & CR-I(-) columns and stationary phases are the newest addition to this family of chiral selectors. The crown ether selectors are immobilized on 5-µm silica support. Immobilization extends the range of solvents used for mobile phases such as acetonitrile and ethanol, thereby enhancing enantioselective resolution of chiral compounds. Use of the immobilized CROWNPAK CR-I(+) & CR-I(-) selectors also provides longer column life time.