Anion Exchange Chiral Stationary Phases - CHIRALPAK® QD-AX and CHIRALPAK® QN-AX columns
CHIRALPAK® QN-AX and CHIRALPAK® QD-AX are enantioselective weak anion-exchange (AX) HPLC columns. They were developed by Prof. W. Lindner’s group in Vienna and are designed specifically for enantioselective HPLC of chiral acids and possess exceptional enantiomer separation capabilities for acidic chiral compounds containing carboxylic, phosphonic, phosphinic, phosphoric or sulfonic acid groups. In some cases, weakly acidic compounds such as phenols can also be separated.
These two columns are based on two complementary stereoisomeric quinine (QN) and quinidine (QD) derivatives. Owing to their pseudo enantiomeric character they usually reveal reversed elution order for opposite enantiomers.
They can be used in reversed phase (RP) mode or in polar organic mode (non-aqueous, polar organic solvents containing organic acids and bases as buffer constituents). In addition the separation of chiral basic and neutral compounds may also be possible, but usually under normal phase (NP) conditions. In this mobile phase mode, CHIRALPAK® QN-AX and CHIRALPAK® QD-AX behave like a standard Pirkle type chiral stationary phase.
They are compatible with all common HPLC solvents (e.g. methanol, acetonitrile, tetrahydrofuran, 1,4-dioxane or chloroform) as well as in a wide pH range spanning from pH 2 to 8. Typical buffers used in hydro-organic mode are acetate, formate, citrate and phosphate.
- N-derivatised amino acids
- Aminosulfonic acids
- Aminophosphonic acids
- Aryloxycarboxylic acids
- N-derivatised peptides